# blew my diyma 12"



## blacklabel (Jan 26, 2006)

last night while in the car auditioning my bg neo3s, i blew my sub. all of a sudden i heard a thud and thought that it was the cat hopping onto my car. today i went to pick up some dog food, popped the truck and it was my sub that i heard blow the night before. i guess i learned my lesson on setting gains TOO high. my gains were turned up more than half way. i was using a pioneer gm-5100 amp, bridged, 380rms give or take. my box was sealed with outside dimensions of 10"L x 13"W x 13.5"H. my question is did my sub blow b/c of my box being too small or did it blow b/c of me trying to compensate with the lack of power from the amp and turning my gains up too high?


----------



## bobditts (Jul 19, 2006)

how did you set your gains?


----------



## Irons82 (May 12, 2006)

cowned...

Too soon?


----------



## kappa546 (Apr 11, 2005)

whoa...


----------



## 89grand (Nov 23, 2006)

That's funny, I did the exact same thing to 2 of them at separate times, and my gains were not set too high.


----------



## blacklabel (Jan 26, 2006)

bobditts said:


> how did you set your gains?


i set my gains for the sub, by ear. when i was setting the gains, it just wasn't hitting like i wanted it to, you could barely notice it when the gains were not even set half way. i guess i should have had an amp that could produce more power.


----------



## 89grand (Nov 23, 2006)

Really, I don't see how more power would have prevented this. I had about 425 watts on tap for mine.

Low power does not rip subwoofer cones.


----------



## kappa546 (Apr 11, 2005)

what size box was it in?


----------



## 89grand (Nov 23, 2006)

kappa546 said:


> what size box was it in?


Are you asking the OP? If so, he said the box was 10"x13."x13.5". I'm assuming that is outside dimensions.
If you were asking me, my enclosure was .83 ft3 before driver displacement, so just under .7 ft3.


----------



## kappa546 (Apr 11, 2005)

man thats not encouraging. ah well, i'm very happy being subless right now tho


----------



## blacklabel (Jan 26, 2006)

89grand said:


> Really, I don't see how more power would have prevented this. I had about 425 watts on tap for mine.
> 
> Low power does not rip subwoofer cones.


yeah, i should have thought about that before i stated it


----------



## 89grand (Nov 23, 2006)

I don't know. The Diyma sub clearly has a specific purpose. It sounds very good, but doesn't seem to like to be driven hard at all.

While a great sounding sub, it's clearly not meant for everyone as the Diyma users seem to be split. About 50% have no issues and defend it to the death, the other 50% either end up with ripped cones, voice coil noises due to buckled cones etc and generally end up pissed off. Considering the amount of Diyma's out there, which is quite low compared to most other subs, there is an awful lot of damaged ones.

In my honest opinion, if you like to get loud at all, avoid this sub completely. If you don't every play your system THAT loud, and are mainly concerned with SQ, then the Diyma is a great choice.

I know it's billed as a SQ sub, but I think it should be noted too, that it's quite fragile as well.


----------



## DonutHands (Jan 27, 2006)

looks familiar


----------



## blacklabel (Jan 26, 2006)

i am pretty disappointed. after days of being in the n.carolina heat and humidity of making a box and finally getting it in, now this happens. i dont know whether to be mad at myself for user error or what.


----------



## blacklabel (Jan 26, 2006)

internecine said:


> looks familiar


damn, we have twins!


----------



## npdang (Jul 29, 2005)

So sorry to hear that. I really hate to see such a great sub go down like that. I really don't think these subs are fragile at all, but rather too overbuilt for it's purpose. In other words, because of the lowish efficiency, combined with the a high stroke motor, massive coil, and light cone people are much too easily able to overdrive these things mechanically. Unfortunately, many of the same things that make it such a great sounding sub also make it far easier to destroy when used outside it's intended purpose.


----------



## npdang (Jul 29, 2005)

89grand said:


> I don't know. The Diyma sub clearly has a specific purpose. It sounds very good, but doesn't seem to like to be driven hard at all.
> 
> While a great sounding sub, it's clearly not meant for everyone as the Diyma users seem to be split. About 50% have no issues and defend it to the death, the other 50% either end up with ripped cones, voice coil noises due to buckled cones etc and generally end up pissed off. Considering the amount of Diyma's out there, which is quite low compared to most other subs, there is an awful lot of damaged ones.
> 
> ...


I think that's the problem when you're selling something over the internet, you really don't know how people are going to use it. I've had a 100% success rate with all the subs I've tuned/installed personally... and I think it has to do with the fact that I know exactly where the limits of the driver are and the people who are buying it know exactly how it should sound and what they are getting... rather than trying to make it into something it's not and then blowing it.


----------



## DonutHands (Jan 27, 2006)

ive got a new one here and am worried about damaging it. i had my gains set at 1/4 when i ripped a hole in it.


----------



## FoxPro5 (Feb 14, 2006)

I had mine at lower power than yours (330w) and really ran it hard and noticed nothing or heard nothing unusual. I agree with NPD, that sub is overbuilt in many ways...maybe it's seen as license for some to run it harder than it can handle?


----------



## maniacmech (Jul 31, 2005)

OK so what is a safe way to run this sub?

I have two brand new in box that I have not had a chance to install yet.


----------



## maniacmech (Jul 31, 2005)

OK so what is a safe way to run this sub?

I have two brand new in box that I have not had a chance to install yet.


----------



## blacklabel (Jan 26, 2006)

i just went GHETTO guys. i used black tape focusing on the part of the sub that was blown. then i came back with duct tape over the whole inner cone. will take pictures later for a good laugh. i dont have the money right now to buy another sub at the moment, but the sub is still going strong. it would be something that i would never show to anyone in person.


----------



## newtitan (Mar 7, 2005)

sorry Im from the ghetto, and Id never do that to a subwoofer LOL

you need to find another term for that one

LOL BLACK TAPE

PLEASE post a picture lol


----------



## 89grand (Nov 23, 2006)

I'm just hoping for an explanation as to how a subwoofer gets destroyed because it's "over built". Or how how a subwoofer gets destroyed by NOT using enough power. 

Personally, I think the cone is too thin for the excursion abilities, and motor strength of the subwoofer. It seems to be a mismatch between the cone and the rest of the speaker.

I'm all ears if there is another logical explanation.


----------



## unpredictableacts (Aug 16, 2006)

could RE/Fi do a recone and give it a beefier yet still light wieght cone?


----------



## 89grand (Nov 23, 2006)

unpredictableacts said:


> could RE/Fi do a recone and give it a beefier yet still light wieght cone?



I don't know. I hope not since I threw both of mine in the garbage can and are now long gone.


----------



## unpredictableacts (Aug 16, 2006)

89grand said:


> I don't know. I hope not since I threw both of mine in the garbage can and are now long gone.


LOL LOOOOOHZER!


----------



## newtitan (Mar 7, 2005)

wow you threw all that engineering in the garbage whoooaa. yeah the cone is light, but geez tc sound will recone almost anything for a price


----------



## npdang (Jul 29, 2005)

89grand said:


> I'm just hoping for an explanation as to how a subwoofer gets destroyed because it's "over built". Or how how a subwoofer gets destroyed by NOT using enough power.
> 
> Personally, I think the cone is too thin for the excursion abilities, and motor strength of the subwoofer. It seems to be a mismatch between the cone and the rest of the speaker.
> 
> I'm all ears if there is another logical explanation.


Exactly my point! It is a huge mismatch, but my priority wasn't to build a high excursion SPL monster... but a super small box SQ sub. And to do that I needed low thermal and bl compression, as well as low distortion. Although I don't personally believe in it, many people hold the opinion that a thin and light cone provides better resolution as well. 

Now when you have a motor that strong, it makes it much easier to damage the soft parts like the cone and the suspension. You have to look at what was purpose this driver actually designed for... before saying whether it's overbuilt or just fragile.

As far as power... just a matter of semantics. Yes, more power will ruin any driver faster. However, it's not always the case that using a more powerful amp will destroy a driver before using a weaker one.


----------



## npdang (Jul 29, 2005)

89grand said:


> I don't know. I hope not since I threw both of mine in the garbage can and are now long gone.


That's kind of sad. It cost me over $100+ out of my own pocket to replace that second one for you. I had hoped that after the first one went, that you might've been a bit more careful the second time around?


----------



## sqkev (Mar 7, 2005)

npdang said:


> Exactly my point! It is a huge mismatch, but my priority wasn't to build a high excursion SPL monster... but a super small box SQ sub. And to do that I needed low thermal and bl compression, as well as low distortion. Although I don't personally believe in it, many people hold the opinion that a thin and light cone provides better resolution as well.
> 
> Now when you have a motor that strong, it makes it much easier to damage the soft parts like the cone and the suspension. You have to look at what was purpose this driver actually designed for... before saying whether it's overbuilt or just fragile.
> 
> As far as power... just a matter of semantics. Yes, more power will ruin any driver faster. However, it's not always the case that using a more powerful amp will destroy a driver before using a weaker one.


Would you recommend stiffening up the cone?


----------



## npdang (Jul 29, 2005)

maniacmech said:


> OK so what is a safe way to run this sub?
> 
> I have two brand new in box that I have not had a chance to install yet.


I would watch the excursion on the low end, as well as clipping on the amp. I find that most people with 2 don't have any problems as it's usually those with 1 looking for more output that are pushing the sub beyond it's limits.


----------



## unpredictableacts (Aug 16, 2006)

sqkev said:


> Would you recommend stiffening up the cone?


A cone erection if you will....


----------



## npdang (Jul 29, 2005)

chasm said:


> i just went GHETTO guys. i used black tape focusing on the part of the sub that was blown. then i came back with duct tape over the whole inner cone. will take pictures later for a good laugh. i dont have the money right now to buy another sub at the moment, but the sub is still going strong. it would be something that i would never show to anyone in person.


I have a friend running one like that that I had returned to me. He put some deadener over the crack and it's working really well for him. He absolutely loves it, especially since it was free lol.


----------



## npdang (Jul 29, 2005)

sqkev said:


> Would you recommend stiffening up the cone?


I wouldn't. If you wanted something like that, you could just buy any one of a dozen other subs that would give you more output. If you're using it for SQ, it's already more than strong enough.


----------



## 89grand (Nov 23, 2006)

npdang said:


> That's kind of sad. It cost me over $100+ out of my own pocket to replace that second one for you. I had hoped that after the first one went, that you might've been a bit more careful the second time around?


I realize that you sent me the second one for "free". Free meaning that I didn't pay for it, yet I paid for the first one that went south without any warning after only a month worth of use.

The second one took a **** the day I installed it, the very same day. I figured if I'm going to use it, I don't want to be affraid of it, so I installed, played it fairly loud and it fell apart in less than 5 minutes. The plus to that was that I didn't have to waste time wondering if it would last or not. In all honesty, I thought the first one failing was a fluke, so I figured I'd see what the second one was made of. Well, I found out.

Really though, if I knew you sent me the second one assuming I'd ***** foot around with it, I would have told you not to bother. I expect my audio equipment to perform as it should, and I won't keep anything that doesn't. I replaced the Diyma's with an RE Audio SE12, and I never adjusted anything, and not only does it sound nearly as good, it plays louder and hasn't fallen apart. It's a better subwoofer for me and my intended use.

I don't mean any disrespect, but if I knew then what I know now, I would have never bought the first one. You are out $100, and I'm out $140, so nobody won anything here.

Anyway, I repect your knowledge on car audio, and really enjoy your website. It's been a pleasure to be here, but your subs do not suite my purpose and perform as I think they should. We both payed the price for that I imagine.


----------



## sqkev (Mar 7, 2005)

89grand,
did you take pictures? I'm interested in seeing how the cones came apart. You didn't want to recone the subs? (maybe through TC?) the motors are too damn nice to be thrown away.

npdang,
thanks for the response


----------



## 89grand (Nov 23, 2006)

sqkev said:


> 89grand,
> did you take pictures? I'm interested in seeing how the cones came apart. You didn't want to recone the subs? (maybe through TC?) the motors are too damn nice to be thrown away.
> 
> npdang,
> thanks for the response


I have pictures of the first one, where the cone buckled in several places. The second one buckled at first then actually ripped like the pictures you've seen in this thread.

I felt bad tossing them as they really are a sweet looking speaker, but I didn't really know what to do with them. They're heavier than crap so it wasn't that practical to be shipping them back and forth. It would have ended up costing me more to have a recone, than just buying a different sub. I had thought about doing something, I just didn't see anything that practical.


----------



## blacklabel (Jan 26, 2006)

that is what scares me, the shipping on these beasts if someone ever decides to get a recone done on these subs. with the price of the recone and shipping, will it all be worth it in the end? right now, PE has a special on Dayton HO subs, for $99. I might try to find some money to get one, but i dunno.


----------



## skylar112 (Dec 8, 2005)

89grand said:


> I don't know. The Diyma sub clearly has a specific purpose. It sounds very good, but doesn't seem to like to be driven hard at all.
> 
> While a great sounding sub, it's clearly not meant for everyone as the Diyma users seem to be split. About 50% have no issues and defend it to the death, the other 50% either end up with ripped cones, voice coil noises due to buckled cones etc and generally end up pissed off. Considering the amount of Diyma's out there, which is quite low compared to most other subs, there is an awful lot of damaged ones.
> 
> ...



I think your comment is rather ignorant. If you like it loud avoid this sub completely? Many have heard my diyma with 400-1000w and are bewildered at how loud and clean it is. The sub is not that fragile it no more fragile than the 10W6V2, Audiomobile Mass12 or any other sub that I've owned. It seems to me you are one of the few that are having problems with this sub. And I thought in your previous posts you were going to stop bashing this sub as great service has been provided to you because you blew it a few times. I honestly think its user error as everyone that I know that has one has NO problems with it what so ever from 200w all the way to 1200watts. We are all entitiled to our opinions, but from what I understand you have been taken care of far and beyond ANY company or person would take care of. If you don't like the product so be it, but no need to talk trash about the product. You're the type of person that makes customer service a nightmare.


----------



## durwood (Mar 7, 2007)

I'd have to agree with npdang. The market on car audio subs has changed drastically over the years. Everything has switched over to these monster excursion subs and so most people have gotten used to that. I have had a few subs that were not loud but they were designed for SQ purposes. 

I'll give a perfect example: Infinity beta 10. It's also an SQ sub designed to go into a small sealed box. RMS power rating on it is 500Wrms, but it doesn't have the excursion to move alot of air. It sounded nice but I always tried to push them too hard to get more output. The cone is an injection molded poly and I had one cone crack. It didn't buckle because its not aluminum, and I was able to glue it back together and it works fine now. This whole DIYMA just reminds me and I thought I would pass it along. Bottom line is, if you crack the cone, then you need to find a different sub better suited for your needs.


----------



## SOHCKing03 (Nov 21, 2006)

I agree. I only have 200 watts going to mine and it is still loud. When I turn up the volume it feels as if the sub is about to rip. So pushing it past its limits is obviously gonna blow it. This sub is tagged as an SQ sub capable of producing clean sound while still having plenty of output. If you wanted high output then you should have gotten a different sub. If you blew a sub doing one thing, why the heck would you get another one and do the same thing to it?!?!

My DIYMA has been going strong for over a week now and I do not forsee any problems. Push anything past its limit and you will have problems.

I do not see why there is all the DIYMA bashing. It is not defined as a high output, so do not be upset if it doesn't have high output. It is not defined as SPL, so do not be upset if it doesn't win an SPL competition. It is for SQ, so use it for that.

-Brad


----------



## SteveLPfreak (Sep 26, 2005)

durwood said:


> Bottom line is, if you crack the cone, then you need to find a different sub better suited for your needs.


True. I've used one for several weeks with 2kw RMS on it (I switch between a Massive Audio P3000.1 and they LP 4.1 HVS.) I've got (2) other friends who each have one with about 500W to them for several weeks. No problem whatsoever. Everyone loves their sound.

No one likes to admit operator error. The DIYMA12 is somewhat inefficient and should be taken into account when using it.


----------



## ClinesSelect (Apr 16, 2006)

89grand said:


> I felt bad tossing them as they really are a sweet looking speaker, but I didn't really know what to do with them. They're heavier than crap so it wasn't that practical to be shipping them back and forth.


There might have been someone local who would have been happy to take them off your hands rather than pitching them in the garbage can.


----------



## 89grand (Nov 23, 2006)

skylar112 said:


> I think your comment is rather ignorant. If you like it loud avoid this sub completely? Many have heard my diyma with 400-1000w and are bewildered at how loud and clean it is. The sub is not that fragile it no more fragile than the 10W6V2, Audiomobile Mass12 or any other sub that I've owned. It seems to me you are one of the few that are having problems with this sub. And I thought in your previous posts you were going to stop bashing this sub as great service has been provided to you because you blew it a few times. I honestly think its user error as everyone that I know that has one has NO problems with it what so ever from 200w all the way to 1200watts. We are all entitiled to our opinions, but from what I understand you have been taken care of far and beyond ANY company or person would take care of. If you don't like the product so be it, but no need to talk trash about the product. You're the type of person that makes customer service a nightmare.


Ignorant huh? The 2 Diymas I had didn't seem to care too much for getting loud. Apparently your idea of loud is not the same as mine. My opinion on this is no more ignorant than yours is. Maybe if I heard yours I might think, wow is that just an 8" because you may choose to listen to your music at a much lower volume than I do. 

I'm not "bashing" the Diyma, I'm giving my honest opinion of it in my system with my experiences with it, positive or not, I'm not sure why my opinion is upsetting some people here. I've recommended the Diyma to a number of people here even after what happened to me, but I always suggest that if they like to pound on their subs,they should look elsewhere. I think that's a pretty honest assessment myself. 

User error? How so? The thing with this sub is that it got pretty loud and sounded great, I ran it for over a month, then one day after a fairly loud listening session it developed voice coil noise. It gave no warning that I could tell. So how exactly is one to know how loud they can play it before the cone falls apart? I'm running a different sub in the same setup and play it just as loud if not louder sometimes and it's still intact.

As far as being well taken care of, I'm certainly not the first person that received a new sub because of noise issues. I didn't ask for another sub, even though I wasn't that pleased with buying one only to have it crap out within a month or so. Npdang offered to send me a new one and I told him that I appreciated the offer, but that I wasn't asking for another one I was just telling him about the noises I had. I have to check my PM's, but I think I even offered to pay for the shipping. He sent me another one anyway, which I did appreciate, but it took a **** too. I never asked dpdang to do anything about the second one, or the first one either. So if that makes me a customer service nightmare, I hope you never own a company.  

In the end, the number of people that have had problems definetely leads me to believe that this is a highly specialized subwoofer that should only be used by people that fully understand it's limitations, whatever they may be. I knew it was an SQ sub, but that doesn't really tell the whole story, and it certainly doesn't tell you how loud you can play it before it gets pissed. It's a great sub for what it's designed to do, but not everybody knows it's limitations until it's too late.


----------



## B&K (Sep 20, 2005)

89grand said:


> The second one took a **** the day I installed it, the very same day.


Sounds to me like not only do you have an install issue but don't learn from your mistakes either. Since you were stubborn you are out money, NP is out money, and now you are stinking up the place. Perhaps next time you should take some advice when it is given to you instead of doing the exact opposite.


----------



## DonutHands (Jan 27, 2006)

> I knew it was an SQ sub, but that doesn't really tell the whole story, and it certainly doesn't tell you how loud you can play it before it gets pissed. It's a great sub for what it's designed to do, but not everybody knows it's limitations until it's too late.


i agree with you there. there were no signs that the cone was going to warp before it did. sounded great, then sounded like ****.


----------



## backwoods (Feb 22, 2006)

skylar112 said:


> I think your comment is rather ignorant. If you like it loud avoid this sub completely? Many have heard my diyma with 400-1000w and are bewildered at how loud and clean it is. The sub is not that fragile it no more fragile than the 10W6V2, Audiomobile Mass12 or any other sub that I've owned. .


 
no offense, but you are wrong.

I've never seen ripped cones on the 10w6 except from someone dropping a drill on it.

The problem is, people are throwing numbers around like crazy. One guy says he has ~400 watts and the cone ripped. Another claims 1000 watts with no problem.

Either the QC is bad, or people really have no idea how much power and how hard they are pushing these things. I think it would be much safer to call them a 250watt sub and leave it at that. If you go over 250, then you void any type of warranty and np should not have to do anything to help you.

Also, it would help if people quit saying the sub was overbuilt. That makes users assume they can punish this with no problems.


----------



## 89grand (Nov 23, 2006)

B&K said:


> Sounds to me like not only do you have an install issue but don't learn from your mistakes either. Since you were stubborn you are out money, NP is out money, and now you are stinking up the place. Perhaps next time you should take some advice when it is given to you instead of doing the exact opposite.



Yeah, I'm glad you can see my install through your computer, that's great. So what are your recommendations for improving my install?


Do some of you guys have reading comprehension problems? The first sub developed voice coil noises one day, why? Who knows, no one else knew either. On the second one, the cone buckled, why? I still don't know, but I'm glad to see that many of you believe pure speculation is all that's needed to determine that it was "user error" whatever that general statement means. Exactly what was the advise that I received and was too stubborn to accept? I don't recall geting any advice. And if the advice I had received was just, don't listen to it very loud, that wouldn't have cut it anyway.

Again, just because I don't think the Diyma is the right subwoofer for everybody, I'd hardly consider that "stinking up the place". Well unless you only want to hear praise for every piece of gear regardless of what someones experiences where with it.


----------



## FoxPro5 (Feb 14, 2006)

I'm curious if during testing npdang if you put this thing to its limits? Aren't the RMS rating based on that??


----------



## durwood (Mar 7, 2007)

I'm pretty sure he did otherwise to make claims of 1000wrms would be dangerous. 

I'm curious, how thick is the cone anyway? Comparing it to some other drivers, is it Seas L18 thick or Eclipse/TC, or Alumapro thick?


----------



## Boostedrex (Apr 4, 2007)

89grand said:


> Low power does not rip subwoofer cones.


I really hate to jump into the fire on this one, but that statement isn't really correct bro. Low power + incorrectly set gains = clipping and destroyed subs. A lot of people will set their gains too high to try and get a desired output and end up clipping their amps. Where if you have plenty of headroom on your sub amp your are WAY less likely to set your gains too high. I know that you're not a noob, nor are you stupid. But I do think that you can get a bit aggressive when talking about your experiences and you list your opinions more as a fact than an opinion. That's why people tend to jump on your case.


----------



## solacedagony (May 18, 2006)

I'm not taking any sides here but I also buckled the cone on my DIYMA last week. I actually didn't even notice it because the sound didn't change at all. I just happened to be cleaning out my car and noticed it looked weird. Low and behold, there were a couple points where the cone had bent. I'm still playing it and it's still sounding good. For how long, I'm not sure. I love the sound of the sub and I'm gonna play it until it dies.

Np said none of the ones he used blew, so I'm gonna chalk it up to not knowing what I'm doing, as I know a hell of a lot less than most of you.


----------



## 89grand (Nov 23, 2006)

Boostedrex said:


> I really hate to jump into the fire on this one, but that statement isn't really correct bro. Low power + incorrectly set gains = clipping and destroyed subs. A lot of people will set their gains too high to try and get a desired output and end up clipping their amps. Where if you have plenty of headroom on your sub amp your are WAY less likely to set your gains too high. I know that you're not a noob, nor are you stupid. But I do think that you can get a bit aggressive when talking about your experiences and you list your opinions more as a fact than an opinion. That's why people tend to jump on your case.



I'll say this, my first response was correct. Low power DOES NOT rip subwoofer cones and I stand by that statement. In my setup, my amp has enough balls to get the output I want without running the gains too high.

In a case of a low powered setup with gains too high trying to achieve output that the amp can't deliver can indeed destroy subwoofers, but it does it through burnt voice coils not ripped cones.

The thing is, over excursion is what will rip an aluminum cone, and you need power to get excursion. A low powered amp may be distorting like hell and burning up the voice coil, but it still can't move the cone so far as to rip it that I could see.

I hope this came across as not _too_ aggresive!


----------



## durwood (Mar 7, 2007)

I'm not so sure over excursion will rip a cone, surround yes, however it might buckle aluminum once the mechanical limits are reached but rippping cones sounds like it more related to pressure. 

I'll agree with 89, clipping does not rip cones. Clipping destroys voicecoils.


----------



## backwoods (Feb 22, 2006)

Boostedrex said:


> I really hate to jump into the fire on this one, but that statement isn't really correct bro. Low power + incorrectly set gains = clipping and destroyed subs.


nope....


by the way, lots of users with buckled and ripped cones...


If I had a truck that had a heavy duty frame, with a big v12 putting out 800 hp and 1200 ft lbs, and the frame could handle pulling 24,000 lbs, but I can't claim that if the tranny is only rated for 400 ftlbs. If I tell everyone the truck is overbuilt, then it is my fault when I get all these blown trannies...

I think this was a result of alot of the hype from users stating over and over about how overbuilt the sub is, and how much power their amp is rated for.

I would assume from reading all the reviews, that I could put 1000 watts and run it all day. But, if you have 1000 watts on it, and have the gains all the way down you may not be running 1/10 of that, so user b puts a 600 watt amp on it, and throws a test tone, gets a true 600 watts, and there goes the cone.

Hence why I said it may be better to advertise it with a reccommended power rating around 250, then when they hit 400-600 they know they are pushing the mechanical limits of the sub, obviously the thermal limits are much higher....


----------



## durwood (Mar 7, 2007)

Something else to look at might be the surround. Rubber surround becomes very non-linear at higher excursions. You will notice this if you press down hard on the cone, foam on the other hand is more forgiving and is usually more linear in high excursion case. I suspect two things COULD happen,

1) the surround is non-linear @ high excursion causing the cone to buckle and destroy itself.

2) The cone is too thin or not strong enough to deal with pressures in a smal box past a certain power rating lower than THERMAL power rating of 1000Wrms.

Another question I'd like to ask, is the cone a flat cone or is curvlinear?


----------



## 89grand (Nov 23, 2006)

durwood said:


> I'm not so sure over excursion will rip a cone, surround yes, however it might buckle aluminum once the mechanical limits are reached but rippping cones sounds like it more related to pressure.
> 
> I'll agree with 89, clipping does not rip cones. Clipping destroys voicecoils.


Yeah, I should rephrase that. I ended up with a buckled cone first, then it ripped.


----------



## DonutHands (Jan 27, 2006)

solacedagony said:


> I'm not taking any sides here but I also buckled the cone on my DIYMA last week. I actually didn't even notice it because the sound didn't change at all. I just happened to be cleaning out my car and noticed it looked weird. Low and behold, there were a couple points where the cone had bent. I'm still playing it and it's still sounding good. For how long, I'm not sure. I love the sound of the sub and I'm gonna play it until it dies.


it may rip apart soon. at first my cone buckled. i told npdang about it, he said that the sub could still be used with the buckled cone and maybe use it as a home theatre sub where the cone will not be visable. so in the mean time waiting for a replacment sub i turned the gains way down and continued to use the sub, 2 days i had a hole in the cone.


----------



## solacedagony (May 18, 2006)

internecine said:


> it may rip apart soon. at first my cone buckled. i told npdang about it, he said that the sub could still be used with the buckled cone and maybe use it as a home theatre sub where the cone will not be visable. so in the mean time waiting for a replacment sub i turned the gains way down and continued to use the sub, 2 days i had a hole in the cone.


Thanks for the warning. I'll keep an eye on it so I don't end up with a similarly functioning amplifier.


----------



## MarkZ (Dec 5, 2005)

Boostedrex said:


> I really hate to jump into the fire on this one, but that statement isn't really correct bro. Low power + incorrectly set gains = clipping and destroyed subs. A lot of people will set their gains too high to try and get a desired output and end up clipping their amps. Where if you have plenty of headroom on your sub amp your are WAY less likely to set your gains too high. I know that you're not a noob, nor are you stupid. But I do think that you can get a bit aggressive when talking about your experiences and you list your opinions more as a fact than an opinion. That's why people tend to jump on your case.


Can someone please explain to me how a clipped signal is going to rip a cone?


----------



## npdang (Jul 29, 2005)

solacedagony said:


> I'm not taking any sides here but I also buckled the cone on my DIYMA last week. I actually didn't even notice it because the sound didn't change at all. I just happened to be cleaning out my car and noticed it looked weird. Low and behold, there were a couple points where the cone had bent. I'm still playing it and it's still sounding good. For how long, I'm not sure. I love the sound of the sub and I'm gonna play it until it dies.
> 
> Np said none of the ones he used blew, so I'm gonna chalk it up to not knowing what I'm doing, as I know a hell of a lot less than most of you.


Similar to my experience as well. Even the cracked cones, once patched with some deadener sound perfectly fine. If anyone wants to send their subs to me I know of quite a few people locally who would love to have one and would even pay the shipping.


----------



## npdang (Jul 29, 2005)

MarkZ said:


> Can someone please explain to me how a clipped signal is going to rip a cone?


I can't explain it, but I have observed where using a lower power amp ~400w and driving it hard into heavy clipping causes all sorts of rattles, pops, and possibly buckling of the cone. 

I can listen to the same song with a 1kw amp with dynamic peaks barely clipping, and not have any issues. Just looking at how the sub moves it just seems "cleaner" and less violent.

I can also put the driver through the Klippel with a constant 300w for over 30 minutes getting usable data out to almost 40mm peak to peak and not have any issues whatsoever.

I agree with you though, clipping doesn't cause driver failure per se, but in alot of cases it tends to go hand in hand with alot of other things such as thermal and mechanical failure.


----------



## solacedagony (May 18, 2006)

npdang said:


> Similar to my experience as well. Even the cracked cones, once patched with some deadener sound perfectly fine. If anyone wants to send their subs to me I know of quite a few people locally who would love to have one and would even pay the shipping.


If it does crack, I'll have to give that a shot. Thanks for the tip.


----------



## npdang (Jul 29, 2005)

backwoods said:


> nope....
> 
> 
> by the way, lots of users with buckled and ripped cones...
> ...


Very true, but I think you're overlooking the fact that it is highly dependent on what the truck is being advertised for. If it was marketed toward hauling heavy loads, you'd have an issue. If it was targetted for say a movie prop that was going to be hauling fake paper logs then clearly it does the job well and could even be considered overbuilt.... but if some guy took it to a construction site and tried to haul some steel beams with it then what would you say?


----------



## MarkZ (Dec 5, 2005)

npdang said:


> I can't explain it, but I have observed where using a lower power amp ~400w and driving it hard into heavy clipping causes all sorts of rattles, pops, and possibly buckling of the cone.
> 
> I can listen to the same song with a 1kw amp with dynamic peaks barely clipping, and not have any issues. Just looking at how the sub moves it just seems "cleaner" and less violent.
> 
> ...


Maybe high frequencies are extending to breakup modes that are somehow resonating at the cone's max pliability? I'm having trouble figuring out what could be the cause. 

Where does the DIYMA break up anyway?


----------



## blacklabel (Jan 26, 2006)

all taped up...


----------



## 89grand (Nov 23, 2006)

chasm said:


> all taped up...


Wow! All that tape, that's gotta alter some of the drivers characteristics.


----------



## npdang (Jul 29, 2005)

89grand said:


> I realize that you sent me the second one for "free". Free meaning that I didn't pay for it, yet I paid for the first one that went south without any warning after only a month worth of use.
> 
> The second one took a **** the day I installed it, the very same day. I figured if I'm going to use it, I don't want to be affraid of it, so I installed, played it fairly loud and it fell apart in less than 5 minutes. The plus to that was that I didn't have to waste time wondering if it would last or not. In all honesty, I thought the first one failing was a fluke, so I figured I'd see what the second one was made of. Well, I found out.
> 
> ...


I'm not trying to come down on you in any way, so please don't feel offended. It's just hard to communicate "feelings" over the internet.

I just think that you could have sold the driver if it didn't work for you rather than destroying it in 5 mins? I could be wrong, but I thought that the first one went on you because you cranked it hard in the car wash to show up some guy?

The only problem I had was the 50/50 comment. I've sold to hundreds of people, and it's not close to 50/50 by any stretch, or I wouldn't even bother to sell these things. It's more like a few users, who continually have the same problem which leads me to believe, as you said that this sub isn't for everyone. 

Although I do strongly disagree with your other comments. For me I can hear a noticeable difference between a sub with 1.3mh inductance and flatter bl curve, than one that's pushing 4mh+ with a more parabolic curve. Buf of course if you're looking for loud and sq to you is that the driver doesn't crap out or play one note bass, then you're probably not going to hear a big difference.


----------



## blacklabel (Jan 26, 2006)

89grand said:


> Wow! All that tape, that's gotta alter some of the drivers characteristics.


yeah, there were also multiple other breaks in the cone that you prob. can't see in the pic and i didn't bother mentioning about. also, when you press the cone down on the upper right corner of the sub, there is some kind of knock. it's like something is loose and hitting against something else, but it is only in the top right hand corner of the sub and nowhere else.


----------



## npdang (Jul 29, 2005)

MarkZ said:


> Maybe high frequencies are extending to breakup modes that are somehow resonating at the cone's max pliability? I'm having trouble figuring out what could be the cause.
> 
> Where does the DIYMA break up anyway?


Cone breakup at 1.5khz pretty high q/amplitude. I have an FR plot I can post later.

It's a mystery to me as well ... sort of. I definitely know it has something to do with mechanical overexcursion in the lower frequencies.

I notice with certain songs like Andrea Zonn, there's really strong subsonic content that causes drivers to "pop out" really hard for a brief moment. It's tough to deal with because it's hard to hear such low frequencies. When you take such a thin cone and heavy coil... popping hard is not a good thing. Whereas other songs with higher fundamentals ~40hz like a lot of trance I listen to get pretty darn loud without any issues.

I tend to tune with alot of cuts below 60hz, and sometimes I use a subsonic filter ~30hz if I think the customer is one that likes to crank and that's been pretty successful for me.


----------



## npdang (Jul 29, 2005)

chasm said:


> yeah, there were also multiple other breaks in the cone that you prob. can't see in the pic and i didn't bother mentioning about. also, when you press the cone down on the upper right corner of the sub, there is some kind of knock. it's like something is loose and hitting against something else, but it is only in the top right hand corner of the sub and nowhere else.


I think that maybe because you're pushing unevenly on the cone. You have to push straight in with even force applied, otherwise the coil may not go straight into the gap.


----------



## MarkZ (Dec 5, 2005)

npdang said:


> Cone breakup at 1.5khz pretty high q/amplitude. I have an FR plot I can post later.


Oh. That is high. Nevermind. 



> It's a mystery to me as well ... sort of. I definitely know it has something to do with mechanical overexcursion in the lower frequencies.
> 
> I notice with certain songs like Andrea Zonn, there's really strong subsonic content that causes drivers to "pop out" really hard for a brief moment. It's tough to deal with because it's hard to hear such low frequencies. When you take such a thin cone and heavy coil... popping hard is not a good thing. Whereas other songs with higher fundamentals ~40hz like a lot of trance I listen to get pretty darn loud without any issues.


Not sure how clipping would exacerbate that problem, unless the driver's impedance goes up real high at low frequencies and the harmonics are making their way through at low impedances.  But I doubt the impedance curve is that steep at low frequencies. I'm sure it approaches the DCR or thereabouts.


----------



## Boostedrex (Apr 4, 2007)

MarkZ said:


> Can someone please explain to me how a clipped signal is going to rip a cone?


Alright, sorry about the bad post. I was in a hurry this morning. I have personally seen speakers torn apart due to clipped signals though. Not that it's common at all, but it does happen. (yes I know that almost anything is possible given the right situations so don't waste your time going there.)


----------



## kappa546 (Apr 11, 2005)

chasm said:


> all taped up...


 Baller. how does that thing sound? lol


----------



## 89grand (Nov 23, 2006)

The first one did go south at the car wash. I was running it pretty hard, but I don't recall getting any warning that failure was coming, well until it was too late and I heard the voice coil noise, or whatever it was.

With the second one, I didn't set out to destroy it for fun, I'll admit I did give it a mini torture test to find out if it would survive the long haul, I didn't want to think it was cool for a while then crap out when I least expected it. I thought it was possible that the first failure was a fluke. Well I drove around the block running it fairly hard, came back home, popped the trunk and there was another buckled cone. 

The 50/50 is definetely an exaggeration. I know you've sold quite a number of them on ebay. Here on Diyma though, I think it's been more than 3 or 4 people with issues. I've PM'ed by more people than that about them having noise issues or ripped cones too.

Anyway, I'm long passed it. I hoped the sub would suite my needs and it didn't. Oh well, it's not the first piece of gear that didn't work for me.


----------



## 89grand (Nov 23, 2006)

npdang said:


> I think that maybe because you're pushing unevenly on the cone. You have to push straight in with even force applied, otherwise the coil may not go straight into the gap.


On the first one that went noisy, I noticed the same thing. Lightly knocking around the cone resulted in banging noises from the voice coil in the gap, but only in one isolated area. It didn't around most of the cone.

I think, and I'm completely speculating, but when the cone buckles I would think it would now throw the voice coil out of aligment with the gap, depending on where the coil buckled.


----------



## blacklabel (Jan 26, 2006)

kappa546 said:


> Baller. how does that thing sound? lol


it is still going pretty strong. i have the gain for the sub turned down now, so it doesn't pound as hard as it did before. you can't hear any mechanical noises unless you physically press it down. i listened to it in my room before putting it back in the car. i set the x-over pt to 80Hz and it blends in so much better than set at 63Hz. only time will tell now. i kinda wish i had something to cover it up, in case i had to open my trunk up with someone around.


----------



## 89grand (Nov 23, 2006)

chasm said:


> i kinda wish i had something to cover it up, in case i had to open my trunk up with someone around.


LMAO!


----------



## demon2091tb (May 30, 2005)

I really don't know, all of it sounds to me like user fault, i may be completely wrong, but i've never had a problem with my diyma, and i have 500w on it, and have it bumping nicely at times, depending on music, but honestly how loud are you guys playing them, i have my playing levels on my HU set much lower than where i tuned at for additional headroom, so no clipping issues. I've done GEQ cutts -1db if need be around 63 because of a slight overkick, and at 40hz because of a natural peak in the car, but other than that its fine.......you may need more midbass if your having to crank it that freaking loud. I let mine blare at times but never once have had a problem.

User error, or just different tastes this sub isint suited too?


----------



## kappa546 (Apr 11, 2005)

demon2091tb said:


> I really don't know, all of it sounds to me like user fault, i may be completely wrong, but i've never had a problem with my diyma, and i have 500w on it, and have it bumping nicely at times, depending on music, but honestly how loud are you guys playing them, i have my playing levels on my HU set much lower than where i tuned at for additional headroom, so no clipping issues. I've done GEQ cutts -1db if need be around 63 because of a slight overkick, and at 40hz because of a natural peak in the car, but other than that its fine.......*you may need more midbass if your having to crank it that freaking loud.* I let mine blare at times but never once have had a problem.
> 
> User error, or just different tastes this sub isint suited too?


indeedio. for gods sake he just deadened his doors. 

anyways, for my tastes in bass i dont think i would ever have a problem with the diyma (i've only used it briefly and i hope i'm not wrong, i dont want a dead sub either). everyone that jumps in my car either: A. doesn't realize i have a sub or B. knows i do and asks me to turn it up. people just dont get it... i mean i'm happy being subless right now and think it's plenty of low end for me with the SLS8's  this could also be the 3 months of being audioless talking though


----------



## exmaxima1 (May 31, 2007)

durwood said:


> Something else to look at might be the surround. Rubber surround becomes very non-linear at higher excursions. You will notice this if you press down hard on the cone, foam on the other hand is more forgiving and is usually more linear in high excursion case. I suspect two things COULD happen,
> 
> 1) the surround is non-linear @ high excursion causing the cone to buckle and destroy itself.
> 
> 2) The cone is too thin or not strong enough to deal with pressures in a smal box past a certain power rating lower than THERMAL power rating of 1000Wrms.


I have been engineering metal cone speakers exclusively for 15 years, and I seen many ripped cones over this time. There are actually many things that can cause this, some are production or engineering defects, while others are due to mis-applications of the woofers.

Without actually examining a DIYMA woofer, I cannot comment on the engineering. I'm sure there may be issues with the cone or surround geometries, the depth of the anodizing, the cone alloy, or even the adhesives. But I can comment on the box size and frankly I think the box size quoted by the OP is ridiculously small for a woofer of this potential.

It has been shown in various studies that the air within a sealed box becomes significantly non-linear when compressed or rarified more than 5% of its volume. So a 12-inch woofer with an true Xmax of 23MM would need a box of at least .90 Ft3 to avoid audible distortion at full excursion, and 1.0-1.2 Ft3 would certainly sound much better. Regardless of what the T-S alignment amounts to, a box big enough to prevent over compression of the air will sound much more dynamic and effortless. 

In addition, a small box increases the differential pressure on the cone which stresses it and can cause it to buckle/bend/break. Or the pressure can cause the surround to break loose at one point on the cone, which cracks the cone and quickly snowballs to a shattered cone.

The one question I have is has anyone ever verified that the surround can indeed support an Xmax of 23MM? That is an incredible Xmax claim, and few surrounds can do that. It has been my experience, especially with Asian subwoofers, that the voice coil/motor may be capable of 23MM, but the rest of the suspension is not up to the task. So, as one poster noted, the surround may be tugging at the cone and bending it. It may only take a few bends to crack the cone....

Matthew


----------



## ArcL100 (Jun 17, 2005)

chasm said:


> i kinda wish i had something to cover it up, in case i had to open my trunk up with someone around.


Why, I'd open my trunk to show it off (no sarcasm)!

Kentucky-Chrome-Cone Sub. That's so DIY it hurts.

-aaron


----------



## 60ndown (Feb 8, 2007)

exmaxima1 said:


> I have been engineering metal cone speakers exclusively for 15 years, and I seen many ripped cones over this time. There are actually many things that can cause this, some are production or engineering defects, while others are due to mis-applications of the woofers.
> 
> Without actually examining a DIYMA woofer, I cannot comment on the engineering. I'm sure there may be issues with the cone or surround geometries, the depth of the anodizing, the cone alloy, or even the adhesives. But I can comment on the box size and frankly I think the box size quoted by the OP is ridiculously small for a woofer of this potential.
> 
> ...


very interesting and informative, thankyou......


----------



## npdang (Jul 29, 2005)

Xmax figures are quoted taking both motor and suspension limits into account.

It's not necessarily my intention either that the driver be used to full xmax, but rather even half of that is more than sufficient to ensure what I would consider good output for a SQ based setup... especially when utilized within a region of less than 5 or 10% bl loss.


----------



## khail19 (Oct 27, 2006)

kappa546 said:


> indeedio. for gods sake he just deadened his doors.


This cracks me up! No offense meant to 89grand, but you did go on about not needing any deadening for a while. Then you finally did it and saw a huge improvement, just as most do the first time they do deadening. Maybe you are in a similar situation with your sub. The DIYMA really is a SQ sub intended for a different purpose than the RE you have now, maybe your idea of "not that loud" is different from other people's definition. I know that personally I've never needed more than 400w on any single sub to get plenty loud for my tastes, and I think my setup has more sub-bass than a true SQ setup usually does.


----------



## B&K (Sep 20, 2005)

MarkZ said:


> Maybe high frequencies are extending to breakup modes that are somehow resonating at the cone's max pliability? I'm having trouble figuring out what could be the cause.
> 
> Where does the DIYMA break up anyway?


If someone has one near Mpls I'd be glad to hit it with the scanning vibrometer and measure the breakup modes.


----------



## CBRworm (Sep 1, 2006)

I had a failure, Got a free replacement and am now using the speaker in the house with great success. I found that with a subsonic filter there is no failure. 

What I realized is that it looks like the motor has the power to pull the cone into the frame. First it hits the backside of the terminals - buckling it at 2 points, if driven harder it will hit the spider support all the way around the cone, buckling it around the whole circumference and possibly ripping it. 

I did a lot of experimenting with my damaged speaker and could drive it with low frequency sinewaves into its own frame in a 1 cf sealed box using fairly low power from a high power amp. When I put it into a smaller sealed box it was harder to drive it to lightly touch the terminals, but when I ran some higher frequencies through it the cone ripped and blew outward. I suspect that the cone was weakened first, then ripped later.

NPDang took great care of me throughout the whole process and I am now much happier with this speaker in my HT than I was with the Klipsch sub-12 that it replaced.

For the price I paid for the speaker I cannot complain. In my car I am now using a 12W6V2 which I have been driving much harder and has not complained once. I paid about 3 times as much for the JL as I did for the DIYMA. For SQ applications I have no doubt that the DIYMA is a great sub. For single speaker SPL - it is not a good choice. It does not have the built in protection of mainstream speakers. The JL I could send (I wouldn't try it) DC to the driver and I don't think it would hit the frame. I did some testing with the same sinewaves and the same amps and same box, etc, No point on the JL moving assembly can be driven anywhere near the frame before the motor runs out of power. The JL doesn't have the excursion, or the potential output - but it is bulletproof. The DIYMA has the potential, but you have to be careful. It is like a bike with lots of power, it requires a lot of wrist control to keep from hurting yourself. Get on a 600 (the JL) you can twist the throttle to the stop, it's not going to flip over or spin the tire. the DIYMA is like a 1000 - you twist too fast or too far, you are going to land on your head - but the potential is there to go faster than on the 600 if you can control yourself.


----------



## FoxPro5 (Feb 14, 2006)

B&K said:


> If someone has one near Mpls I'd be glad to hit it with the scanning vibrometer and measure the breakup modes.


I gots one. But I just blew it listening to some 3-6Mafia yoz. J/K. Would there be a crema topped espresso involved here?


----------



## 89grand (Nov 23, 2006)

khail19 said:


> This cracks me up! No offense meant to 89grand, but you did go on about not needing any deadening for a while. Then you finally did it and saw a huge improvement, just as most do the first time they do deadening. Maybe you are in a similar situation with your sub. The DIYMA really is a SQ sub intended for a different purpose than the RE you have now, maybe your idea of "not that loud" is different from other people's definition. I know that personally I've never needed more than 400w on any single sub to get plenty loud for my tastes, and I think my setup has more sub-bass than a true SQ setup usually does.


My point about "deadening" was that I didn't have door vibrations which is what deadening is actually for. Granted, I used the same technique, but I did it soley to seal up my doors. I know deadening does both, but anyway, my point about deadening before was the my doors didn't need to be "deadened", not that they wouldn't benefit from being sealed. 

Midbass response has definetely improved, but I contribute that to 2 things. The Premier 720PRS speakers and sealing the doors. I think the lower in midbass a speaker can play, the more obvious the benefits are to deadening/sealing the doors.

I really don't care though if every single person on this site said the Diyma is more than enough subwoofer for everybody, because I simply don't think so. I'm also not the only person to have had one buckle on them either.

I sold some Vifa Autosound drivers because they didn't have enough midbass for my tastes. The person that bought them thinks they sound great. It's just the way it goes. I now have the Premier 720's and the RE Audio SE12 and right now, I think the system sounds the best it ever has.


----------



## MarkZ (Dec 5, 2005)

khail19 said:


> This cracks me up! No offense meant to 89grand, but you did go on about not needing any deadening for a while. Then you finally did it and saw a huge improvement, just as most do the first time they do deadening. Maybe you are in a similar situation with your sub.


Not only that, but it's hugely dependent on the specific vehicle and its location within the car. The very first thing that people need to try when they're not satisfied with their sub performance is moving it around the trunk. 

Gotta play with installation before you start blaming the equipment!


----------



## backwoods (Feb 22, 2006)

well, someone needs to set me up with 4 of them, and I'll try'em out IB in my car, and see how they do..

NP, you still have 4 left? 

Maybe I just need to buy some and give it a whirl...

by the way, the car isn't an spl vehicle, I just need four for design purposes...


----------



## B&K (Sep 20, 2005)

B-Squad said:


> I gots one. But I just blew it listening to some 3-6Mafia yoz. J/K. Would there be a crema topped espresso involved here?


Coffee is easy to include


----------



## MarkZ (Dec 5, 2005)

89grand said:


> I really don't care though if every single person on this site said the Diyma is more than enough subwoofer for everybody, because I simply don't think so. I'm also not the only person to have had one buckle on them either.


Frankly, I agree with you on that point. No question, the DIYMA is a useful sub for many people, and it looks like it's the right price. But for many people it's NOT a "SQ" sub; any speaker that cannot handle the power delivered to it to fit an application can never be an SQ sub for that application (assuming SQ is the goal). That's not a knock on the DIYMA. It's a knock on the notion that there's such a thing as an "SQ driver" and that if you exceed its limits you must not be interested in SQ.

Ok, so there's not enough output potential for your needs. Have you first checked installation-related aspects of your system so that you can maximize the performance of whatever sub you're using?


----------



## exmaxima1 (May 31, 2007)

backwoods said:


> well, someone needs to set me up with 4 of them, and I'll try'em out IB in my car, and see how they do..


Why would you run them IB? They certainly do not have the T-S parameters for an IB design. Has anyone else tried them IB with success?

Matthew


----------



## npdang (Jul 29, 2005)

They're saying it's more than enough for SQ use. And I'd have to say I agree.

I think CBRworm hit the nail on the head. If you're pushing it hard enough to hit the spider spacer ring and buckle the cone, chances are it's not being used for SQ purposes.


----------



## khail19 (Oct 27, 2006)

89grand said:


> I sold some Vifa Autosound drivers because they didn't have enough midbass for my tastes. The person that bought them thinks they sound great. It's just the way it goes.


It's really too bad you didn't try the deadening before getting rid of the Vifas. I love the Pioneers myself, but it would have been interesting to see how much of a difference was made by sealing up the doors with the same speakers installed. I know the first time I did it the difference was astounding, even with a cheap set of CDT components.



89grand said:


> I now have the Premier 720's and the RE Audio SE12 and right now, I think the system sounds the best it ever has.


This is really all that matters, there's nothing wrong with liking it loud. As long as you're not blasting it in residential areas at midnight.  If you are happy with your setup now, then it's all good.


----------



## npdang (Jul 29, 2005)

MarkZ said:


> Frankly, I agree with you on that point. No question, the DIYMA is a useful sub for many people, and it looks like it's the right price. But for many people it's NOT a "SQ" sub; any speaker that cannot handle the power delivered to it to fit an application can never be an SQ sub for that application (assuming SQ is the goal). That's not a knock on the DIYMA. It's a knock on the notion that there's such a thing as an "SQ driver" and that if you exceed its limits you must not be interested in SQ.
> 
> Ok, so there's not enough output potential for your needs. Have you first checked installation-related aspects of your system so that you can maximize the performance of whatever sub you're using?


Semantics 

For me, I find that once you exceed 110-115db in a car... where's the "quality" in that?


----------



## DonutHands (Jan 27, 2006)

npdang said:


> I tend to tune with alot of cuts below 60hz, and sometimes I use a subsonic filter ~30hz if I think the customer is one that likes to crank and that's been pretty successful for me.


tune mine!


----------



## backwoods (Feb 22, 2006)

exmaxima1 said:


> Why would you run them IB? They certainly do not have the T-S parameters for an IB design. Has anyone else tried them IB with success?
> 
> Matthew


 
The drivers I am currently using can easily reach 50 hz and below. The combination of a low fs and an IB config would give an incredible low end. Also, may help the cone stay more linear without compression being an issue and low power requiements and minimal excursion needed from having the cone area from 4 drivers, may help in avoiding any buckling.


----------



## MarkZ (Dec 5, 2005)

npdang said:


> They're saying it's more than enough for SQ use. And I'd have to say I agree.


But, as is true with most speakers, that's highly dependent on the listener preferences and the specifics of the car/installation. To use an extreme example, even you might acknowledge that a single DIYMA 12 on 400w may not be "more than enough for SQ use" in a large van. 

Or to use another example, would you consider the Alpine XT19 tweeter to be a tweeter suitable for "SQ"? If so, then what's wrong with the people who have found that they can't get enough output out of them without distortion or even frying them? Does that necessarily mean they're not using them for "SQ" purposes?

I know I've begun to sound like a broken record in here regarding this issue, but_ there most certainly is a relationship between SQ and SPL._ If you can't get the output you need for your application, then your speaker is going to sound like ass, no matter how well it measures under 1w testing. A $5 Pyle speaker will probably sound better than a $300 Scanspeak if the Scanspeak's coil is smacking up against the top plate and the Pyle is operating within its linear range.

How much is enough output? It's certainly going to depend on what you consider to be "loud enough", and what the dynamics and spectral content of the music you listen to dictate. I can't even begin to emphasize how drastically this differs from person to person.

Not only are there vehicle-specific and listener-specific considerations, but there are also installation-related issues that come into play. Clearly, a sub that's firing directly into the cabin with the trunk walled off is going to sound different from a sub behind the back seat that's battling trunk reflections, or a sub that's sitting at the rearmost corner of the trunk where the reflections are more likely to be coherent. But not everyone can afford to use the optimal location and still fit their groceries or their golf clubs.

Again, I'm not saying the DIYMA is a bad sub. I'm saying just because it doesn't fit someone's needs does not mean that they must have goals other than SQ.


----------



## chad (Jun 30, 2005)

exmaxima1 said:


> It has been shown in various studies that the air within a sealed box becomes significantly non-linear when compressed or rarified more than 5% of its volume. So a 12-inch woofer with an true Xmax of 23MM would need a box of at least .90 Ft3 to avoid audible distortion at full excursion, and 1.0-1.2 Ft3 would certainly sound much better. Regardless of what the T-S alignment amounts to, a box big enough to prevent over compression of the air will sound much more dynamic and effortless.
> 
> In addition, a small box increases the differential pressure on the cone which stresses it and can cause it to buckle/bend/break. Or the pressure can cause the surround to break loose at one point on the cone, which cracks the cone and quickly snowballs to a shattered cone.
> 
> ...


I couldn't agree more, there's a ton of stress on that cone from being in such a small enclosure and if the motor is as hotrodded as stated then I think some of the issues point right there.


----------



## durwood (Mar 7, 2007)

89grand said:


> The first one did go south at the car wash. I was running it pretty hard, but I don't recall getting any warning that failure was coming, well until it was too late and I heard the voice coil noise, or whatever it was.


Well, you will never hear the warning signs if it's in a sealed off trunk, i'm talking slight warnigng signs, not it it's completely bottoming out. 



exmaxima1 said:


> I have been engineering metal cone speakers exclusively for 15 years, and I seen many ripped cones over this time. There are actually many things that can cause this, some are production or engineering defects, while others are due to mis-applications of the woofers.
> 
> Without actually examining a DIYMA woofer, I cannot comment on the engineering. I'm sure there may be issues with the cone or surround geometries, the depth of the anodizing, the cone alloy, or even the adhesives. But I can comment on the box size and frankly I think the box size quoted by the OP is ridiculously small for a woofer of this potential.
> 
> ...


I still find it amazing that it would work in a 0.25cuft box. The usuable range on this sub is quite large. I think there should be a recommended power range chart with different box sizes. Thanks for the great info. 



CBRworm said:


> I had a failure, Got a free replacement and am now using the speaker in the house with great success. I found that with a subsonic filter there is no failure.
> 
> What I realized is that it looks like the motor has the power to pull the cone into the frame. First it hits the backside of the terminals - buckling it at 2 points, if driven harder it will hit the spider support all the way around the cone, buckling it around the whole circumference and possibly ripping it.
> 
> ...


I'm glad someone experimented. It looks like a mechanical excursion issue is the cause, but it's just that it's not designed to take abuse, and as cbrworm has stated the JL will take some serious abuse. I actually had an output stage go on one of my soundtream amp and my JL sat at DC for a good 15/20 minutes while I drove home. It still worked fine, but I swapped it anyway because I could. I don't think alot of subs out there could survive something like that though.


----------



## dBassHz (Nov 2, 2005)

exmaxima1 said:


> ...a small box increases the differential pressure on the cone which stresses it and can cause it to buckle/bend/break. Or the pressure can cause the surround to break loose at one point on the cone, which cracks the cone and quickly snowballs to a shattered cone.


x2 Exactly what I was thinking. 

I auditioned the DIYMA for a couple of minutes and immediately knew that it wasn't for me. It is a great sounding sub in many applications, including IB (T-Ro has 2 IB in his vette). And it would have been perfect for a stealth install because it requires little space. But I have gotten use to higher output subs and I knew that I would need 3 or 4 for the output that I was looking for. For a reference, I have blown one of my XT19 tweeters hi-passed 4,000 @ 18dB.


----------



## npdang (Jul 29, 2005)

I completely agree with you, but I don't think we're on the same page here.

I'm not trying to say that if it doesn't fit someone's needs than their goals aren't SQ related (as is understood in the manner you're speaking of), but rather using the well known convention that "SQ use" implies that you should know what to expect when purchasing and using a driver. Under these circumstances, I do believe the DIYMA should be more than sufficient under typical conditions.


----------



## 89grand (Nov 23, 2006)

npdang said:


> They're saying it's more than enough for SQ use. And I'd have to say I agree.
> 
> I think CBRworm hit the nail on the head. If you're pushing it hard enough to hit the spider spacer ring and buckle the cone, chances are it's not being used for SQ purposes.


Wow! So if I listen to music louder than you or some others here, I'm not using my system for SQ? What was the maximum SPL again that is considered "SQ" for everybody 100db, 105 maybe? I better get an SPL meter so in the future I'll be able to tell when I'm leaving the realm of SQ and into pure SPL, because as it sits now, as long as my system is still clean and has dynamics with no distortion, power compression or any driver noises I thought it still was SQ regardless of how loud it actually was.


I think the bigger problem here is not whether I listen to my stereo system "louder than Diyma standard" but that the woofer can be driven into that situation in the first place with realitively low power.

Some people love the Diyma's and that's great. I don't, so what? I'm not trying to tell anyone that likes their Diyma's that they shouldn't because if they do, they aren't listening to theirs loud enough, anymore than I'll accept others telling me I don't know what I'm doing or what I'm talking about...or even that I don't listen to my system right if I don't. 

Anyway, this is pointless really. I've since moved onto to a different sub that suites my needs. I'm not bitter or pissed about the Diyma not working for me. Everyone here, I think, agrees that it's not the best subwoofer for everybody and I've just tried to let some people know that and why it isn't. I've also touted the Diymas virtues as well.


----------



## DonutHands (Jan 27, 2006)

> using the well known convention that "SQ use" implies that you should know what to expect when purchasing and using a driver.


umm...


----------



## legend94 (Mar 15, 2006)

durwood said:


> Something else to look at might be the surround. Rubber surround becomes very non-linear at higher excursions. You will notice this if you press down hard on the cone, foam on the other hand is more forgiving and is usually more linear in high excursion case.


why do more subs not use foam? is it because of the car environment? 

also, why do more subs not use the surround of the old jbl gti?


----------



## Guest (Jun 4, 2007)

If you would have UNDERBUILT the sub nobody would be complainging!


----------



## durwood (Mar 7, 2007)

legend94 said:


> why do more subs not use foam? is it because of the car environment?
> 
> also, why do more subs not use the surround of the old jbl gti?


There is not one best answer for that. I meant it to be a generalized statement in an effrt to flush out the real reason why a sub might fail mechanically. Each surround serves it's purpose. Rubber has come a long way and there are different rubber surrounds i.e. adaptive. BTW...my JL10W6V2 uses a TREATED foam surround and there are plenty of other subs out there using foam as well. 

Pictures are on there way to show what I mean...hang on









Foam pushed in









Rubber pushed in









See how the rubber dimpled more? Not that it woudl ever reach that point, but it is going to do some things to the cone if it's not flexible enough to work with that or strong enough to withstand non-linearities...if the cone is fragile or brittle then you can have some problems


----------



## 89grand (Nov 23, 2006)

legend94 said:


> why do more subs not use foam? is it because of the car environment?
> 
> also, why do more subs not use the surround of the old jbl gti?



The surround on the RE SE12 is some sort of foam, it feels very strong and robust. The Diyma on the other hand uses a rubber surround that feels very light. I don't know what that has to do with anything, but they are clearly polar opposites. I don't know enough about driver design to have any idea what surround materials play in the overall scheme of things.

It's weird though, you look at the RE and it just looks and feels like it can take a lot of abuse. And it seem to be able to, I'm sure there are downsides to this design as well though.


----------



## legend94 (Mar 15, 2006)

the last car sub that i used that had a foam surround was the old soundstream spl170, but it was a very thick foam. i remember being disappointed when i lifted the damn sub out of the box(it seemed very well built) and it had a foam surround  i think i paid over 400 bucks for it to go with the soundstream 10.0 that i miss dearly :blush:


----------



## npdang (Jul 29, 2005)

Again, I'm not talking about what sound quality means to people here. If you think sound quality is a bose wave radio that's none of my business. But you have to be seriously kidding me if you don't know what that means when someone says intended for SQ use. Ask yourself, when someone says I'm looking for a SQ sub... what's the first thought that crosses your mind? What's the difference when they ask for SQL, or SPL? 

I'll say it again.. I'm not questioning what anyone thinks is SQ. I do question however, the judgement a few people are exercising when they can blow big holes in their cone and say that the sub didn't do what it was advertised to do.


----------



## eqrenthorn (Apr 18, 2007)

In my opinion, SQ = ------- on the RTA meter, minus a few dB cuts here and there for listening pleasure. I've metered my DIYMA 12" at 120 dB, which when playing with the rest of my system near that level, is plenty loud for me. However, due to our lack of sensitivity in the lower regions, a lot of people prefer --\____ when listening to music, which is probably what people are referring to as a drift from pure "SQ".

Sometimes, it's more fun listening to music that way, but if you pop in a good classic/jazz CD, you'll quickly realize how overbloated the low end is if you compare it to a live performance. In other words, while 140 dB from your subs may be tolerable or even fun to listen to for short spurts at a time, 140 dB in the high octaves will have you crying for your mommy.


----------



## 89grand (Nov 23, 2006)

Well, I think of an SQ sub is one that is accurate in frequency response at least in the enclosure it was designed for. Of course once it's in the car, that pretty much all goes out the window since it would have to be tuned for the particular install.

Npdang, you've said it yourself that when someone doesn't like the sound of their sub, it's pretty much tuning related, and that you could tune nearly any subwoofer to sound good, That being the case, then what exactly is the definition of a SQ sub? I don't necessarily think it should mean it can't be driven past a certain unknown point. And how does anyone know what that point even is unless they damage the driver?

I'll take full responsibilty for destroying mine if that makes anyone feel better, but I still don't know how I was supposed to be able to tell how loud it would play before it got damaged. I know I wasn't driving the amp into heavy distortion.


----------



## demon2091tb (May 30, 2005)

89grand said:


> Well, I think of an SQ sub is one that is accurate in frequency response at least in the enclosure it was designed for. Of course once it's in the car, that pretty much all goes out the window since it would have to be tuned for the particular install.
> 
> Npdang, you've said it yourself that when someone doesn't like the sound of their sub, it's pretty much tuning related, and that you could tune nearly any subwoofer to sound good, That being the case, then what exactly is the definition of a SQ sub? I don't necessarily think it should mean it can't be driven past a certain unkown point. And how does anyone know what that point even is unless they damage the driver?
> 
> I'll take full responsibilty for destroying mine if that makes anyone feel better, but I still don't know how I was supposed to be able to tell how loud it would play before it got damaged. I know I wasn't driving the amp into heavy distortion.


MY thoughts are something in your truck probobly smacked it, and ripped a hole in it, the excessive pressure in the box (sealed being VERY pressurized at any large excursion) probobly forced a ton of air through the opening, giving it that sectioning effect sorta like a little flapper, as its not in the voicecoil region, and its open to the rear of the sub it was most likely pressure and something hitting it, i'd think. I'm still itching for a grill on mine, everyday i wonder if i'll look out at see a puncture hole from **** in my trunk i can't fit in my backseat.


----------



## Nass027 (Oct 25, 2006)

It has been shown in various studies that the air within a sealed box becomes significantly non-linear when compressed or rarified more than 5% of its volume. So a 12-inch woofer with an true Xmax of 23MM would need a box of at least .90 Ft3 to avoid audible distortion at full excursion, and 1.0-1.2 Ft3 would certainly sound much better. Regardless of what the T-S alignment amounts to, a box big enough to prevent over compression of the air will sound much more dynamic and effortless. 

In addition, a small box increases the differential pressure on the cone which stresses it and can cause it to buckle/bend/break. Or the pressure can cause the surround to break loose at one point on the cone, which cracks the cone and quickly snowballs to a shattered cone.



Matthew[/QUOTE]
So in your opinion this sub should be in a minimum 1.0 Ft3 box preferbly slightly larger than the smaller 0.5+ Ft3 that had been recommended for the SQ purpose?Just trying to gather all the stuff that's been said here as i have to build my box now and want to utilize this sub to it's full potential and not blow it up.I'll be sending it about 700watts from the sub channel on my Audison 5.1k amp.


----------



## 89grand (Nov 23, 2006)

demon2091tb said:


> MY thoughts are something in your truck probobly smacked it, and ripped a hole in it, the excessive pressure in the box (sealed being VERY pressurized at any large excursion) probobly forced a ton of air through the opening, giving it that sectioning effect sorta like a little flapper, as its not in the voicecoil region, and its open to the rear of the sub it was most likely pressure and something hitting it, i'd think. I'm still itching for a grill on mine, everyday i wonder if i'll look out at see a puncture hole from **** in my trunk i can't fit in my backseat.


I know you're just guessing here, but I can assure you that nothing hit it because there wasn't anything else in the trunk. Remember, I had two of them buckle cones. Now, once the cone is buckled, that will become a weak spot in the cone. Continued use must have eventually ripped the cone.


----------



## DonutHands (Jan 27, 2006)

demon2091tb said:


> MY thoughts are something in your truck probobly smacked it, and ripped a hole in it, the excessive pressure in the box (sealed being VERY pressurized at any large excursion) probobly forced a ton of air through the opening, giving it that sectioning effect sorta like a little flapper, as its not in the voicecoil region, and its open to the rear of the sub it was most likely pressure and something hitting it, i'd think. I'm still itching for a grill on mine, everyday i wonder if i'll look out at see a puncture hole from **** in my trunk i can't fit in my backseat.


definately does not take somthing hitting the sub to create a hole.


----------



## sqkev (Mar 7, 2005)

Here's my personal experience with the sub since this is probably the largest thread about known issues of the sub:

I owned the DIYMA for a week or two and I tested it out in both the car and at home. I bought it from someone knowingly it had some knocking issues. Fed it with a pro audio amp rated of 315watts x 2 @ 4ohm and 450watts x2 @ 2ohm, the box was 1 cube. Other equipment includes the deq2496 with clipping indicator, dcx had the same clipping indicator and amp also have the clipping lights built in. 
I ran it at almost full power and only heard the slight knocking noises at high volume, and that's having my head close to the box (within 1 meter). When facing the box away and I step away from it, you cannot hear the popping/knocking noises at all, even at full volume. In the car, I could not hear the knocking noises at all.

With that said, I find it hard to understand how one could rip the cone of the driver like that. Assuming you're one of the few that had a "defect" driver like I did, it still takes a lot to tear up that cone. 

BTW, I have the same issue with the OZ ME (very seldom though). When I set the subsonic filter to 30hz, the problem went away. If you're having a problem with the DIYMA sub, try a subsonic filter at 20hz-25hz and see if there's an improvement.

I'm picking a NIB from another member tomorrow and will do further testing.


----------



## npdang (Jul 29, 2005)

In alot of cases, that is true. Distortion audibility in the bass frequencies is pretty poor, and in most cases you don't need alot of excursion if all you want to do is blend the sub seamlessly into the frontstage. It's then just a matter of frequency response and a smooth transition to the midbass for most people. Some people though will be able to hear subtle differences in distortion performance and bl compression even at these levels, and even the effects of high inductance.

As Mark has pointed out, I don't think there exists a definition of a SQ driver. To me, I think sound quality means meeting whatever criteria you've set forth for what you believe is good sound. But when people commonly talk of SQ... IMHO it's generally accepted that at the least it involves low distortion, clarity, etc. and not so much an emphasis on dynamics... in which case I often see the term SQL often used.

And I do have the same problems you do. I don't know any drivers limit until I've destroyed one. There are always some indicators such as voice coil size, venting, clearances in the motor, mechanical noises, etc. but it's not always foolproof. If you recall I set the Aura sub on fire with very modest amounts of power <200w... even though it looked like it could handle far more.

Rather than using the term SQ which sparked a somewhat long off-topic semantic debate, I think perhaps a more straightforward description could have been used such as seamless blending or transparency etc.


----------



## DS-21 (Apr 16, 2005)

*Abusing the multiquote...*



exmaxima1 said:


> It has been shown in various studies that the air within a sealed box becomes significantly non-linear when compressed or rarified more than 5% of its volume. So a 12-inch woofer with an true Xmax of 23MM would need a box of at least .90 Ft3 to avoid audible distortion at full excursion, and 1.0-1.2 Ft3 would certainly sound much better. Regardless of what the T-S alignment amounts to, a box big enough to prevent over compression of the air will sound much more dynamic and effortless.
> 
> In addition, a small box increases the differential pressure on the cone which stresses it and can cause it to buckle/bend/break. Or the pressure can cause the surround to break loose at one point on the cone, which cracks the cone and quickly snowballs to a shattered cone.


Matthew, thanks for the very interesting post. I have one question for you and one question for DIYMA12 users. For you, if you wouldn't mind I'd enjoy some speculation on cone pressures when the driver is used in John van Ommen's bandpass/horn home sub design.

Also, has anyone tried the DIYMA 12 in a ~90L sealed box? That seems to be optimal for this driver (Qtc=0.5). It will also reach full excursion with 500W at 16Hz. 



npdang said:


> I tend to tune with alot of cuts below 60hz, and sometimes I use a subsonic filter ~30hz if I think the customer is one that likes to crank and that's been pretty successful for me.


IMO, you should make your warranty contingent upon use of an appropriate high-pass filter.



npdang said:


> Although I do strongly disagree with your other comments. For me I can hear a noticeable difference between a sub with 1.3mh inductance and flatter bl curve, than one that's pushing 4mh+ with a more parabolic curve. Buf of course if you're looking for loud and sq to you is that the driver doesn't crap out or play one note bass, then you're probably not going to hear a big difference.


+1.



89grand said:


> but I don't recall getting any warning that failure was coming, well until it was too late and I heard the voice coil noise, or whatever it was.


That's one of the signs of a woofer designed for high-fidelity purists. I don't like "SQ" vs "SPL" or "SQL." In my view, either a woofer strives to offer maximum fidelity to the source material, or it is designed/built to a lesser standard. Most woofers designed for car audio are designed and built to inferior standards than the above, though blessedly this one appears not to be.



89grand said:


> Wow! So if I listen to music louder than you or some others here, I'm not using my system for SQ? What was the maximum SPL again that is considered "SQ" for everybody 100db, 105 maybe?


Once one gets beyond the levels found in a live and unamplified performance (~106dB peaks broad-spectrum in the case of a symphony orchestra playing fff in a hall such as the Philharmonie, Royal Albert, the Musikverein, etc., with a ~20dB lower average level) then fidelity is obviously no longer one's primary concern. Above those levels, or for that matter _at_ them consistently, one is more concerned with fomenting hearing damage than enjoying music reproduced accurately.


----------



## MarkZ (Dec 5, 2005)

eqrenthorn said:


> In my opinion, SQ = ------- on the RTA meter, minus a few dB cuts here and there for listening pleasure. I've metered my DIYMA 12" at 120 dB, which when playing with the rest of my system near that level, is plenty loud for me. However, due to our lack of sensitivity in the lower regions, a lot of people prefer --\____ when listening to music, which is probably what people are referring to as a drift from pure "SQ".
> 
> Sometimes, it's more fun listening to music that way, but if you pop in a good classic/jazz CD, you'll quickly realize how overbloated the low end is if you compare it to a live performance. In other words, while 140 dB from your subs may be tolerable or even fun to listen to for short spurts at a time, 140 dB in the high octaves will have you crying for your mommy.


It's funny how people always use the "live performance" as their benchmark. Um...am I the only one here who doesn't listen to acoustic performances in the park? I go to shows all the time. Close to a hundred over the last 10 years. I hear an "overbloated low end" at almost all of them. And no, you would not be able to reproduce them in every car and in every installation with a single DIYMA 12 at 400w.

As for what constitutes "SQ", our opinions will differ. If we suppose for the sake of argument that our common goal (not taking into account imaging) is a linear transfer function, then I still fail to see how SPL is irrelevant. If you overdrive your speaker or your amplifier, even during brief transients, then you'll introduce distortion. If compression occurs because of heat, then that's another nonlinearity. It's very easy to cause these things to happen if you're pushing your equipment to its limits. Even though the average power you deliver to your subwoofer may be on the order of tens of watts, you can expect the peaks to be on the order of hundreds. Amplifier not capable of delivering it? Distortion. Speaker behavior becomes nonlinear at the corresponding excursion? Distortion.

If you guys think your equipment is not being pushed to its limits under...um..."SQ levels", then you're all nuts.


----------



## legend94 (Mar 15, 2006)

so a subsonic filter = high pass xover on the sub  
im a noob again


----------



## MarkZ (Dec 5, 2005)

legend94 said:


> so a subsonic filter = high pass xover on the sub
> im a noob again


Yep. Generally, a subsonic filter refers to a high pass filter at "subsonic" frequencies (ie. frequencies below the limits of human hearing). The limitation on human hearing isn't a brick wall, nor is it the same for all of us, so it's somewhat arbitrary. Usually you'll see them somewhere between 15Hz and 30Hz though.

For some program material, it can be pretty useful. Personally, I don't think it offers as much protection as some of the others. IME with my crappy music, the natural rolloff below about 40Hz or so is fairly steep.


----------



## legend94 (Mar 15, 2006)

MarkZ said:


> Yep. Generally, a subsonic filter refers to a high pass filter at "subsonic" frequencies (ie. frequencies below the limits of human hearing). The limitation on human hearing isn't a brick wall, nor is it the same for all of us, so it's somewhat arbitrary. Usually you'll see them somewhere between 15Hz and 30Hz though.


the drz9255 has one built in for the sub which i am utilizing. i have mine set at 30hz at a 6db slope. does this sound like a normal setup, or am i missing some frequencies?


----------



## mikechec9 (Dec 1, 2006)

Peace
I would first like to show my adamant appreciation for Npdang for his above excellent customer service and arguably unrivaled overstanding of speakers. As a rule, if I don't have anything pleasant to say about a driver, then I say nothing. But this driver has little to be ashamed of, and in light of the already instituted post, I'll state briefly my personal observations and opinion. I will not go into an elaborate explanation of my history with this driver but will say that I am an owner. 

The driver is truly a great sq sub in that it reproduces the signal as it was originally intended. It is very transparent and smooth at low levels. _Very_ pleasing to the ear. But it is _not_ intended to _ever_ reach its listed 23mm Xmax. No more than the Adire Brahma was ever intended to approach anywhere close to its originally stated '1600w thermal rms.' 

I also believed the first blown sub to have been a fluke, but when it occured a second time, I became hip that it doesn't like to be driven hard...at all, to any degree. First comes the popping at certain frequencies. This causes for a free hand to always be available for corrective tuning, depending on what song is being auditioned. This is already a bother. Then comes the dimples which impugn the integrity of the cone, and so the resulting separation and/or rubbing is going to manifest at some point in time. 

And this is in about .7-.8 cube with only 400w per sub. I repaired the cones with duct tape, which I could have done with any bs Infinity kappa or...xplod for that matter. Basically I'm not pleased about taping together a hi fi reference driver like this one. But the tape actually tamed much of the _higher_ output resonance that I was otherwise hearing, even b4 the cone split. This leads me to believe that with a different cone design, this sub would be more capable of handling the strength of its motor. I have decided to place the driver that Npdang so graciously replaced in the Wife's car, as she doesn't feel the need to drive her system as hard as do I. 

When I originally read 'SQ sub' and reviewed the ts specs and the quality of the driver's build, it led me to believe that the thing could take high output listening. Not a beating per se, but just enjoyment at relatively higher listening levels. And make absolutely no mistake about it here, SQ DOES NOT infer that a sub can't take a beating. Not in 2007 it doesn't. The ID Max, XXX, D9, W7...etc. All of these are pure sq drivers. They just have the capability to play sq at loud levels. And, in the case of most of them, they can actually get snot beat out of them without anything more than the smell of glue curing. But, again, this was never my intent. 

Using the old and outdated paradigm, "sound quality" suggests a concentration of the quality of sound_ in lieu_ of output. But if the demand for sq AND increased output didn't exist, then I don't believe that the above examples of subs would have ever been invisioned, much less created.

So, most basically, I would have sincerely appreciated a lower xmax spec and a disclaimer that not only is this an SQ driver, but that it is NOT intended for high output applications. Of course, if a discrepancy exists between the multiple interpretations of SQ, then there will likewise be one for high output as well. In which case I would still have appreciated a "beware of how hard you drive this thing." And while I'm not a bass head by any means, I (as stated by a previous member) don't pussyfoot around with my subs either...or my Iridiums, lol.

Regardless, the cs I have received far outways any disappointments that I have had with the driver. I am genuinely appreciative of npdang's integrity and subsequent generosity. A classy guy, indeed. I would just like to see the cone altered for the second version of this driver. At which time I would place my (second from the) bottom dollar for a second run. And I truly don't believe that a crossing of the fingers would be necessary.


----------



## blacklabel (Jan 26, 2006)

after the retape of the sub, i am still pleased with it. as i stated in the initial post of this thread, i think it was my fault with going crazy with the gain and i had a small enclosure. but this sub still does what i want it to do. that is: having enough "umph" in the car and no one can tell outside of the car that i actually have a sub in the car. considering this was my first sub enclosure and install, maybe i was expecting more that i was intially getting. with the x-over set @ 80Hz, it sounds much better now versus set @ 63Hz and when the gains were turned up more than half. now, my gains are turned up right at half way. with a lil but more tuning with eq, i am happy.


----------



## backwoods (Feb 22, 2006)

easy fix, if it aint loud enough, buy two!


----------



## t3sn4f2 (Jan 3, 2007)

89grand said:


> The first one did go south at the car wash. I was running it pretty hard, _*but I don't recall getting any warning that failure was coming*_, well until it was too late and I heard the voice coil noise, or whatever it was.
> 
> With the second one, I didn't set out to destroy it for fun, I'll admit I did give it a mini torture test to find out if it would survive the long haul, I didn't want to think it was cool for a while then crap out when I least expected it. I thought it was possible that the first failure was a fluke. Well I drove around the block running it fairly hard, came back home, popped the trunk and there was another buckled cone.
> 
> ...



Do you listen to the sub firing in the trunk threw the rear seats, I ask because I can't hear a subs signs that its being pushed beyond its limits in that type of setup.


----------



## 89grand (Nov 23, 2006)

t3sn4f2 said:


> Do you listen to the sub firing in the trunk threw the rear seats, I ask because I can't hear a subs signs that its being pushed beyond its limits in that type of setup.


True, so again I ask, how would I know that I was driving it too hard, it certainly didn't seem like I was?

My current sub doesn't complain when driven just as hard and probably even harder.


----------



## t3sn4f2 (Jan 3, 2007)

Couldn't you tell the point where they can not take anymore by putting your ear to it in your trunk and not passing those established settings when listening in the car. You could even leave a little headroom for music thats more demanding then the one you used to set the gains the initial time.


----------



## demon2091tb (May 30, 2005)

t3sn4f2 said:


> Couldn't you tell the point where they can not take anymore by putting your ear to it in your trunk and not passing those established settings when listening in the car. You could even leave a little headroom for music thats more demanding then the one you used to set the gains the initial time.


I set my gains with my HU volume set at 32/35 sub output set on 13, and sub level set on 0, then for blending very well with music and an established headroom, i back the output down to 10, and -2 for level matching and a 40hz xover point 12db, when setting at 56hz 24db -3 is a for level matching, this gives me both headroom from the amp audibly clipping at that origional volume level and having plenty of volume with the whole system at no more than 25/35 also depending on source material.

I know i have plenty of volume for any type of music, though based on xover points and such i've only had good performance from my diyma, no doubts and no questions asked about this sub, granted i'm about to put another in the car just for that extra headroom on cone displacement, and overall higher output without running into problems, as a single is plenty for MY daily driving, yet i crave another for the sake of having the substage last though any setup i deal with and on, they will be used if there still in running order, i very much feel as excited about the diyma as i do the Tempest when i ran it, though the diyma kills it in fidelity, the output is very considerable from both, even though the tempest has the displacement advantage......hehe somehow there compraible in my mind for depth of extension and clarity, though the diyma does win easily


----------



## Guest (Jun 5, 2007)

89grand said:


> I know you're just guessing here, but I can assure you that nothing hit it because there wasn't anything else in the trunk. Remember, I had two of them buckle cones. Now, once the cone is buckled, that will become a weak spot in the cone. Continued use must have eventually ripped the cone.



Maybe you have mice in your car?


----------



## legend94 (Mar 15, 2006)

big john said:


> Maybe you have mice in your car?


or rats


----------



## exmaxima1 (May 31, 2007)

backwoods said:


> The drivers I am currently using can easily reach 50 hz and below. The combination of a low fs and an IB config would give an incredible low end.


My issue was that if you do not have a small sealed box to raise the Qts of the driver, then you get overdamped (thin) bass. Also, a low Fs is indicative of a massive cone or very loose suspension, both of which will limit cone control as you push the driver harder.

Better IB parameters, especially to complement a car's acoustic response, would be an Fs of 40-50 hz, and a Qts no less than 0.5. A Qts of 0.7-0.9 would be even better and would yield a rich, yet tight, bass response extending below 20 hz in a car.

Matthew


----------



## DonutHands (Jan 27, 2006)

anyone know of some subs with a high Qts?


----------



## Lightninghoof (Aug 6, 2006)

Subwoofers with a high Qts/Qms? The Alpine Type-X is the first to come to mind. For the most part, a subwoofer with a high Qts/Qms is going to be optimized for a sealed box, and often times will yield a very low anechoic F3 in even a smallish sized sealed chamber. The downside/drawback to this design usually being the low SPL efficiency per watt of input power and/or large box size requirements. The major upside is usually extreme low-end sensitivity and extension in only a moderate sized sealed enclosure.

You'll find that most car audio subwoofers are hybrid designs that attempt to equally optimize the driver for both sealed and vented use. Mid Q, mid Fs, mid EBP designs that don't really excell in any one area. Small box or ultra small box requirements are also the trend. These drivers usually lack low-end sensitivity and extension in order to gain overall SPL efficiency and maintain very small box requirements.

I was in the same boat, I wanted a high Q driver with an extremely robust and extended low end in a sealed box. After many months of research I chose the 12" Alpine Type-X.


----------



## kappa546 (Apr 11, 2005)

internecine said:


> anyone know of some subs with a high Qts?


the ascendant audio arsenals had a pretty high qts. also jbl W12gti's have high qts. i'm a fan of high qts/small vas drivers.


----------



## Lightninghoof (Aug 6, 2006)

Kappa just reminded me, the Infinity PerfectVQ is an adjustable Q driver. You can switch it from "Low Q", "Mid Q", and "High Q". Might be exactly what you are looking for.


----------



## dual700 (Mar 6, 2005)

So, the ones who blew their sub, did you guys get em from ebay or from the store?


----------



## 89grand (Nov 23, 2006)

dual700 said:


> So, the ones who blew their sub, did you guys get em from ebay or from the store?



I got mine from ebay, not that it should really matter where it came from, it was still from dpdang.


----------



## dual700 (Mar 6, 2005)

89grand said:


> I got mine from ebay, not that it should really matter where it came from, it was still from dpdang.


You know that if you get it from ebay, there is no warranty, right?
Not trying to side him, but I think he replaced yours, it's more than fair, imo


----------



## solacedagony (May 18, 2006)

dual700 said:


> So, the ones who blew their sub, did you guys get em from ebay or from the store?


I got mine from the store.


----------



## dual700 (Mar 6, 2005)

Did npdang warranty it?


----------



## 89grand (Nov 23, 2006)

dual700 said:


> You know that if you get it from ebay, there is no warranty, right?
> Not trying to side him, but I think he replaced yours, it's more than fair, imo



Well, my input in this thread has never been about my treatment from dpdang, it's about the sub itself.

When I told him about the noises mine developed, I told him I knew it came from ebay and understood it was without a warranty. He did send me another one anyway which was generous on his part.


----------



## blacklabel (Jan 26, 2006)

dual700 said:


> So, the ones who blew their sub, did you guys get em from ebay or from the store?


got order mine from this site.


----------



## khail19 (Oct 27, 2006)

89grand said:


> I got mine from ebay, not that it should really matter where it came from, it was still from *dpdang*.





89grand said:


> Well, my input in this thread has never been about my treatment from *dpdang*, it's about the sub itself.


You know it's npdang, right? Unless you have your own little pet name for him, which is fine too. Just wondering why you keep spelling it wrong.


----------



## dBassHz (Nov 2, 2005)

internecine said:


> anyone know of some subs with a high Qts?


Oz Audio Matrix Elite 

The discontinued Ascendant Audio Atlas also had a variable QTC configuration.


----------



## 89grand (Nov 23, 2006)

khail19 said:


> You know it's npdang, right? Unless you have your own little pet name for him, which is fine too. Just wondering why you keep spelling it wrong.



LMAO! I know it's npdang, I have know idea why I wrote that twice, other than the fact I can't type worth a damn and am always thinking faster than I can type.

Now that I look at it, it's hillarious, dp, but I swear I didn't mean to do that. 

It makes me wonder now, if I've ever done that before.


----------



## solacedagony (May 18, 2006)

dual700 said:


> Did npdang warranty it?


No, I didn't ask him to. I'm guessing it was my fault so it's not his responsibility to warranty it.


----------



## khail19 (Oct 27, 2006)

89grand said:


> It makes me wonder now, if I've ever done that before.


7 times total.  

http://www.diymobileaudio.com/forum/search.php?searchid=257055


----------



## t3sn4f2 (Jan 3, 2007)

khail19 said:


> 7 times total.
> 
> http://www.diymobileaudio.com/forum/search.php?searchid=257055


Forum rules state immediate banning after the 8th time


----------



## npdang (Jul 29, 2005)

You guys are sick  Although I like the sound of DP700 

The funny thing about high q woofers... they're usually made that way (in car audio at least) to give an exaggerated bass response in a sealed enclosure, not for IB use.


----------



## 89grand (Nov 23, 2006)

At least I'm not the only one. 

http://www.diymobileaudio.com/forum/showthread.php?t=361&page=2&highlight=dpdang


----------



## backwoods (Feb 22, 2006)

exmaxima1 said:


> My issue was that if you do not have a small sealed box to raise the Qts of the driver, then you get overdamped (thin) bass. Also, a low Fs is indicative of a massive cone or very loose suspension, both of which will limit cone control as you push the driver harder.
> 
> Better IB parameters, especially to complement a car's acoustic response, would be an Fs of 40-50 hz, and a Qts no less than 0.5. A Qts of 0.7-0.9 would be even better and would yield a rich, yet tight, bass response extending below 20 hz in a car.
> 
> Matthew


your looking for a smooth response in a larger range then I need. I'm merely looking for presence from 45hz and down.

Increase the number of drivers, reduce the amount of power, the cone will be nice and linear, the low qts value will give me a nice tight bass response, and with the inherent transfer function in the vehicle, I'll actually need to turn down the output with less then 200 watts on each driver. 

It's worked well so far. In fact, it's worked great with aluminum cone drivers...


----------



## demon2091tb (May 30, 2005)

npdang said:


> You guys are sick  Although I like the sound of DP700
> 
> The funny thing about high q woofers... they're usually made that way (in car audio at least) to give an exaggerated bass response in a sealed enclosure, not for IB use.


Dang i think you just like the DP part.....

I mean he called you dpdang 7 times right, i think you just like having the DP part near your name.....


----------



## SteveLPfreak (Sep 26, 2005)

DP should stand for Damn Patient 'cause there's a couple of users that I'd be real tempted to block.


----------



## 89grand (Nov 23, 2006)

SteveLPfreak said:


> DP should stand for Damn Patient 'cause there's a couple of users that I'd be real tempted to block.



Yeah all users that do not walk in step shall be blocked.


----------



## exmaxima1 (May 31, 2007)

backwoods said:


> the low qts value will give me a nice tight bass response, and with the inherent transfer function in the vehicle, I'll actually need to turn down the output with less then 200 watts on each driver.
> 
> It's worked well so far. In fact, it's worked great with aluminum cone drivers...


But try a woofer with Fs of 45 hz, and Qts of .5-.7 sometime

You will be shocked at the clarity and seamless integration to the rest of your system.

Matthew


----------



## 3.5max6spd (Jun 29, 2005)

exmaxima1 said:


> But try a woofer with Fs of 45 hz, and Qts of .5-.7 sometime
> 
> You will be shocked at the clarity and seamless integration to the rest of your system.
> 
> Matthew


I think i prefer a lower FS at least in the low 30's IB.The Dynaudio mw190 is simply music to my ears, def can play flat down to 20hz.


----------



## backwoods (Feb 22, 2006)

exmaxima1 said:


> But try a woofer with Fs of 45 hz, and Qts of .5-.7 sometime
> 
> You will be shocked at the clarity and seamless integration to the rest of your system.
> 
> Matthew


 
I've used the JL free air series and the dayton IB drivers, among a few others. They work great, but i've actually enjoyed the low q drivers IB the best.

A higher FS is great for a normal 80- and down install, easy to tune to get a nice smooth response, and remarkably flat, but in this instance, I have a ton of tuning power, and really only a need for the lowest octave.


----------



## exmaxima1 (May 31, 2007)

3.5max6spd said:


> I think i prefer a lower FS at least in the low 30's IB.The Dynaudio mw190 is simply music to my ears, def can play flat down to 20hz.


That driver has a Qts above 0.5, which is in the ideal range. Though it has a lower Fs than I would recommend, the combination of lower Fs and being slightly overdamped complement the typical automotive acoustics. It looks like it would be a good sounding woofer of average output (9 MM Xmax).

BTW, I've never seen a 10-inch subwoofer touted for car use that recommends a sealed box of 2.0-4.0 Ft3 of airspace! Perhaps it really is best for IB, or nearly IB, after all...

Matthew


----------



## legend94 (Mar 15, 2006)

durwood said:


> There is not one best answer for that. I meant it to be a generalized statement in an effrt to flush out the real reason why a sub might fail mechanically. Each surround serves it's purpose. Rubber has come a long way and there are different rubber surrounds i.e. adaptive. BTW...my JL10W6V2 uses a TREATED foam surround and there are plenty of other subs out there using foam as well.
> 
> Pictures are on there way to show what I mean...hang on
> 
> ...



just found this from weeks ago.
thanks for the photos, it helped with the point you were making.


----------

