# SI MAG v4 D2 -- REVIEW



## theRESONANCE (Aug 28, 2008)

First of all, i would like to thank DIYMA and most of all Nick of Stereo Integrity for giving me such an opportunity.

Because my car was temporarily out of order, Listening was done locally with Elvisjer (member of diyma forums). Thanks again. :]

*Initial thoughts:*
Package arrived in perfect condition as well as on time. From the moment I unboxed the SI, I was greeted with optimism. I was immediately welcomed by several of Nick's promotional items; Two T-shirts and a couple of Decals. Edging to the point, i unboxed the Sub itself not knowing what to expect.- To be honest I was completely curious as to how such a unique subwoofer profile would respond. The build quality is superb and assuring: Clean glue joints and neatly soldered terminals. The sub itself is only 5 1/2 inches tall.. a big plus for installations !!

The only problem that i had was when installing the sub. (If it's a problem at all) The Trim ring which surrounds the sub is a bit thick and difficult to deal with. However since there was two of us, it wasn't such a big problem.. I would recommend getting a friend to help hold it off while you mount it in. However with such a big payback in return, Such a thing wouldn't deter me at all.

I will be comparing with several other subs as well.
*SI MAG v4 D2 & DIYMA R12*


*Equipment Used used:*
The Si Mag v4 d2 and the Diyma r12 were positioned in a 1 cubic ft. sealed box, 3/4" MDF wood. A bit big for the diyma's original 'recommendations'. 
All subs were played from a JL 1000/1. Sensitivity was adjusted accordingly. For the most part, set on lower than usual. No time was given for the Mag to 'break in'. Fresh out of the package into the box, then juiced.

*Tracks :*
For the most part, Focal's Demo disks were used- mainly to test blending and tone. Several tracks from Tech N9ne were also used to test authority, power, and quickness. Other random tracks were used for recreation and curiosity.

*Listening :

*First up.. DIYMA R12".. "Seriously..guys- Where is it?". *blank stare*...
To my dismay, the r12 was the least favorite from the pack...however, I am the type of person who seeks a little thump. So i admit, i am bias towards the r12. Don't get me wrong here, It's a great sub and its SQ is outstanding. But in due comparison with the SI MAG.. it was nothing close. Maybe my ears aren't 'audio-phile' quality.. But i don't understand what the hype is all about. 
I think it would take about 2-3 Diymas to equal a single Mag.
While I understand that the sub was designed to be completely transparent and undetectable..I can't imagine how anyone could rock out to anything but classical music on it. If you're looking for a 40-pounder that won't disturb the stingy neighbors..This is the sub for you! 
Overall, just not my cup of tea. I'm sure it suits others' well.
*
Mag : *Blending was incredibly easy. No matter what track we threw at the Mag, it never let up. Even when we tracked up the low pass to 100hz..it never skipped a beat. Never did it have a problem reproducing down low either. It was transparent and blending when needed to be.. throughout the Focal tracks, But did not hold a thumb back when we wanted big thumping for tracks such as Tech N9ne's. Rather than classifying it as an SQ pure sub.. I would feel more than safe to say that it could pass as an SQL.-
With 1000 watts on tap, The Mag put up like a champ and showed no sign of abuse whatsoever. The sound is full and warm. It would be HARD for anybody in my opinion to dislike the sub-
My favorite was when we put it up to a speed test with Tech N9ne's "Stamina" intro...It literally felt like my heart was speeding up with the beat. It knocked hard and surprisingly quick!..--As fast as my 8w7's. There is no doubt in my mind.. This sub has serious cajones.

Overall ? -- Quick, Powerful, Full, Clean, Low. Enough said.-Wait, did i mention _Shallow mount ?
_this may very well be one of the most 'safest' of subs. Having the capability to suit almost any genre in my opinion. However i have only heard 8 different subs through my experience... 
If you're looking for your next sub, look no further.. Si Mag v4 d2. you will not be dissapointed ! Hands down you won me. congrats Nick and everyone at Stereo integrity for designing such a sub!

I am thinking on getting a 2nd !


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## quality_sound (Dec 25, 2005)

Interesting. With the Mag in a 1cf and the DIYMA in .75cf the DIYMA walked all over the Mag in Zach's xB. And I mean, it wasn't even close. Even on tracks with "big thumping bass" it still killed it. And that was crossed at 63Hz. I'm supposed to listen to his car again tomorrow with the LP at 100Hz and a larger box for the Mag.


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## Electrodynamic (Nov 27, 2007)

And in comparison, Zach and theRESONANCE think otherwise. 

I think everyone needs to keep in mind that "to each his own". Not everyone is going to think the same thing about every driver. That's why there are mutliple drivers to choose from. If there was a definitive champion no matter what, there would only be one high-end subwoofer manufacturer. That's what makes this world really great - everyone likes something different.


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## quality_sound (Dec 25, 2005)

Electrodynamic said:


> And in comparison, Zach and theRESONANCE think otherwise.
> 
> I think everyone needs to keep in mind that "to each his own". Not everyone is going to think the same thing about every driver. That's why there are mutliple drivers to choose from. If there was a definitive champion no matter what, there would only be one high-end subwoofer manufacturer. That's what makes this world really great - everyone likes something different.


NOW, Zach thinks differently. When I listened to the Mag he and I had pretty much the same impression. He's changed boxes and crossover points since then. I'm FULLY expecting there next go round to be quite a different story. 

My main point of contention with the above review was with the DIYMA though. How he could listen to it and say it has no "thump" or that it wold take 2-3 to equal a Mag is, quite frankly, the exact opposite of my experience.

But I am also a fair person, Nick. I will revisit my original review thread and make the necessary updates. 

Fair enough?


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## Electrodynamic (Nov 27, 2007)

Fair enough. I just don't like dumping on other people's reviews. I wouldn't personally do that to another person's review.


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## mvw2 (Oct 2, 2005)

Impact is perceived as loudness. If you can feel it, you don't so much need to hear it.

The problem with the DIYMA is it doesn't hit you. The sound is just there. It's either quiet, right, or overbearing relative to the rest of the system. It just lacks the visceral aspect that is perceived as output. You can listen to a DIYMA sub rather loud and not consider it to _play_ loud.

It's really semantics and mental interpretation. It's kind of like distortion equaling output. Awareness equals loudness.

The DIYMA will disappoint a lot of people. It doesn't do what a lot of people want. Impact is one area. The information is there, but it will never kick you in the chest.

All of this is a matter of "best fit."

In some cases I would prefer the DIYMA. In some cases I would prefer my Sonicraft (punchier, lower F3, and nearly as transparent, better sensitivity). For example, in home, I can't use my DIYMA sealed. It just doesn't play low enough and is anemic in the environment. The Sonicraft has a F3 of 30Hz and provides the depth sealed. The DIYMA ported works great though. In a car, it's a different story and the early roll off is less of an issue. The DIYMA ported is bloated and needs to be EQed down. The DIYMA sealed is a better fit. The Sonicraft sealed is nearly perfect in frequency response in my car (not a lot of cabin gain so low F3 of 30Hz is ideal). In many ways I prefer my Sonicraft sub over the DIYMA. It fits a number of my applications better and is more fun to listen to. In raw SQ, the DIYMA wins, but it has generally shown to require more work to get it to fit great.

The Mag v4 will have it's own fit, and this fit will be different then the DIYMA. As has been stated, it offers a more visceral experience with more punch and listener engagement. It's a larger box sub with a good bit more sensitivity, nice for low power applications. The DIYMA offers more mechanical excursion, but in a SQ setup, it will never make use of this advantage.

The Mag v4 seems like a sub I'd like. I'm just not willing to drop change on one nor have a place to make use of one.

Remember, not everyone likes the same toppings on their pizza. We all like different flavors. This arguing is kind of like people telling you that you taste things wrong.


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## Boostedrex (Apr 4, 2007)

I agree with your thoughts on the Mag. It's an amazing sub. I also think that it truly shines once you let it play a larger pass band. From 100Hz and down in 1 ft^3 sealed, the Mag is really something to rave about.

I couldn't disagree more with your findings on the DIYMA R12, but that isn't the issue at hand. If you don't like it, then it might not be your taste and that's cool too. It was nice to read a review other than mine that compares these 2 subs head to head. Thanks to you and Elvisjer for taking the time to do this review and post it up.

Zach


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## theRESONANCE (Aug 28, 2008)

A review is just the least i could do for such an awesome sub.
As for the r12. I'm sorry if i have offended others. 
However, i believe mvw2 described it the best. Perhaps i'm just a bass head and expected too much because of all the hype. Again, nothing against the driver. It does EXACTLY what it was made for. I'm glad others love it, and mad kudos to npdang for creating a truly unique signature true to his intentions.
The driver was in a 1 cu space with 1000 on tap. perhaps my setup wrong from the get-go?
But as i recall I didn't feel a thing whatsoever. I would love to experience what everyone is talking about. If i am doing something wrong, please feel free to bring it to my attention. I'm always willing to learn. :]


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## quality_sound (Dec 25, 2005)

mvw2 said:


> Impact is perceived as loudness. If you can feel it, you don't so much need to hear it.
> 
> The problem with the DIYMA is it doesn't hit you. The sound is just there. It's either quiet, right, or overbearing relative to the rest of the system. It just lacks the visceral aspect that is perceived as output. You can listen to a DIYMA sub rather loud and not consider it to _play_ loud.


That's what I was getting at. The DIYMA in Zach's xB HAS impact. LOTS of it. That's why I don't understand all the reviews that say it doesn't. Maybe Zach got a ringer?? 

I DO however like the Mag. I like it a lot really. The only knock TO ME was the size of the box...but only when compared to the DIYMA, since when I heard them, they sounded almost exactly the same. I would still take the Mag over ANYTHING else I've heard so far.


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## quality_sound (Dec 25, 2005)

theRESONANCE said:


> A review is just the least i could do for such an awesome sub.
> As for the r12. I'm sorry if i have offended others.
> However, i believe mvw2 described it the best. Perhaps i'm just a bass head and expected too much because of all the hype. Again, nothing against the driver. It does EXACTLY what it was made for. I'm glad others love it, and mad kudos to npdang for creating a truly unique signature true to his intentions.
> The driver was in a 1 cu space with 1000 on tap. perhaps my setup wrong from the get-go?
> But as i recall I didn't feel a thing whatsoever. I would love to experience what everyone is talking about. If i am doing something wrong, please feel free to bring it to my attention. I'm always willing to learn. :]


I don't think anyone is offended. I thought the point of a review was to share your experiences with a product and that the review thread was to ask questions and relate our experiences back. You know, a discussion. But everyone seems to be getting all butt hurt because MY experience seems to be very different from what most of the others have heard so far. If that's the case then maybe we should lock all the review threads so no one can post in them.

I don't have the benefit of having a Mag to listen to daily and to try new things all the time so i have to go with what I hear in a limited time frame...like a judge would. But I am willing to give it all the chances in the world. Whether I like the DIYMA better than the Mag or not (right now, that could change tomorrow) they're both still in my top 5 so it's not exactly like I'm bashing it by ANY stretch of the imagination.


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## Boostedrex (Apr 4, 2007)

Hey, Rodney King would be proud. We're all getting along. ROFL!!

I am very glad to see that the Mag is so well received thus far. It's also nice to know that several other people apparently share the thoughts I do on a driver (the Mag that is). 

Hey Resonance, by chance did you try running the Mag at 4 ohms instead of 1 ohm to see what you thought of it with less power? I think that you'd be amazed at just how nice of a job it will do with only 400-500 watts on it. Also, what this testing all done in Elvisjer's PT Cruiser? How was the sub oriented in the car? Just a few things I'm curious about. For 98% of my testing of the Mag, I had it firing straight up at the roof of my xB in the back right corner of the xB's cargo area/hatch.

Zach


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## theRESONANCE (Aug 28, 2008)

Haha as long as everything is fine. Yes this is just a discussion, No problem at all ! :] As for the diyma.. I'm going to build a .5 for it and see how it goes.


And no i never did try to play the Mag @ 4 ohms. I think i'll try that and see :].. It would be a lot less stress on the sub. And hell, i could just use a 1000 block to power two mags! 
Yes the testing was done in ElvisJer's 3-way Pt cruiser. The sub was positioned in the rear seat-ish area firing straight up to the roof.


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## Boostedrex (Apr 4, 2007)

Awesome, thank you for the added info on the testing. 

Yes, I do think that you should give the Mag a shot at 4 ohms. I think that you'll be pleasantly surprised. Plus the fact that your sub amp will be seeing a higher ohm load will only help to keep things cool and, though inaudible either way, will lower the distortion in the signal that is being fed to the sub. Just some food for thought.


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## quality_sound (Dec 25, 2005)

Not to mention the better control the amp will have over the sub.


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## bassfromspace (Jun 28, 2016)

The DIYMA seems to be REALLY box dependant. This sub saga is very interesting.


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## Electrodynamic (Nov 27, 2007)

I think you'll be surprised when you wire up the Mag for a 4 Ohm load. You'll raise your damping factor as compared to a 1 Ohm load and even if it scales the power down to 500 watts the Mag will still have a plenty of output.


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## thadman (Mar 1, 2006)

I've never heard either driver, although I can offer some potential insight since with subwoofer alignments many of the variables that affect them are intrinsic to the bandwidth. These include modal behavior of the cone (both cones should be relatively pistonic), modal behavior of the listening environment (both drivers are in the same position of the vehicle, interference patterns will be similar), SPL capability (both SHOULD be able to compete with reasonably sized midbass drivers, especially those mounted in doors), etc. With all of this considered, we can look to their waveform tracking and distortion profile to distinguish their performance.

Obviously the transfer function (frequency response) is VERY dependent upon the application and will vary considerably between them. Distortion should also be adequately low for both drivers since they appear to be well engineered, possibly with the DIYMA coming out on top since it was designed for specifically that purpose.

HOWEVER, waveform tracking or dynamic capability may be higher for the Mag (ie improved heat dissipation at higher input levels). 

I would highly recommend having both drivers (if not all considered) complete a klippel analysis as that is really the only way to objectively quantify their performance characteristics. Subjectively comparing the drivers may lead to false impressions about both of them since the variables between them are not able to be controlled. Even if you tuned them so that their frequency responses were very similar, they may not be at the same absolute SPL level. The one with higher SPL will usually sound better...even 1dB.


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## Boostedrex (Apr 4, 2007)

thadman said:


> I've never heard either driver, although I can offer some potential insight since with subwoofer alignments many of the variables that affect them are intrinsic to the bandwidth. These include modal behavior of the cone (both cones should be relatively pistonic), modal behavior of the listening environment (both drivers are in the same position of the vehicle, interference patterns will be similar), SPL capability (both SHOULD be able to compete with reasonably sized midbass drivers, especially those mounted in doors), etc. With all of this considered, we can look to their waveform tracking and distortion profile to distinguish their performance.
> 
> Obviously the transfer function (frequency response) is VERY dependent upon the application and will vary considerably between them. Distortion should also be adequately low for both drivers since they appear to be well engineered, possibly with the DIYMA coming out on top since it was designed for specifically that purpose.
> 
> ...


Great post thadman! And I know that the DIYMA R12 was already Klippel tested. And IIRC, Nick has already offered MVM a Mag v4 to do the Klippel testing with as soon as he is up and running. I really look forward to seeing the results. Because build quality, appearance, and subjective performance are all VERY favorable for the Mag so far.

Zach


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## theRESONANCE (Aug 28, 2008)

+1 . .


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## Electrodynamic (Nov 27, 2007)

I actually offered up a Mag v4 to be Klippel tested a LONG time ago before MVM was picked to house/operate it. In lieu of the current events I'll have a v4 Klippel tested at one of our build houses (no offense to MVM but the Klippel's there have an anechoic chamber for THD and are also bolted down to a couple tons worth of concrete or granite for solid measurements).

I disagree thad though. Looking at both drivers on paper is only going to give you an idea about how each driver is going to perform but it won't tell you the whole story. Actually using your ears is a vital part of reviewing a loudspeaker. Afterall, it is our ears that are the critical part in our listening.  

Transfer function, in this case, is fixed. It is the same vehicle. Both drivers have been positioned in the same position, so that knocks that variable out of the equation. Both drivers were also in the same size box, which should have given the DIYMA the upper hand - seeing as how (by the numbers) the DIYMA has a lower Qtc per said enclosure volume, which _should_ (by the numbers) give it the upper hand concerning transient response / group delay. However, as we've seen from multiple people, that isn't the case in their experience. And lets not forget that the DIYMA has more linear travel (just the higher number itself, not the linearity of the figure even though the linearity of both should be really close) but can't be driven to the level needed to use that amount of travel for fear of the cone developing issues. As some people have eluded to, the DIYMA can handle more power than the Mag can in different enclosures but, again, in real-world experience it can't handle the extra power.

It comes as no surprise to me that some users have preferred the Mag to the DIYMA. On the flip side of the coin, it also comes as no surprise to me that some people have preferred the DIYMA over the Mag. Like I said, different people are going to like different things. In this case we're talking about two linear drivers but one has been specifically designed for 1 ft^3 sealed, weighs ~17 lbs less, is almost 1.5" shallower, and can handle up to 1000 watts. Where the other driver may have had every intention of handling that much power but the soft parts simply won't hold up with that much input. One of the latter is also out of production (last I knew anyway) but can possibly be found second-hand.

PS: Thanks again for the review.


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## quality_sound (Dec 25, 2005)

Electrodynamic said:


> One of the latter is also out of production (last I knew anyway) but can possibly be found second-hand.
> 
> PS: Thanks again for the review.


Technically the DIYMA is out of production but there is still some new stock available and Nguyen has said there is no issue having more made, it's simply a matter of demand. 

I got a chance to listen to the Mag again this weekend. I'll post my thoughts in my review thread.


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## elvisjer (May 13, 2008)

Sorry! I didn't know this post was up yet otherwise i would have chimed in! I can vouch that the DIYMA did not have the thump or impact of the MAG, the 2x 8w7s, or my JVC arsenal which makes me assume the box was too large in fact. We wanted it to sound good, we tried hard. We adjusted EQs and sensitivity to get what we expected/desired in relation to the other tested subs, but it just didnt perform the same. What it DID do was very cool though. When we blasted the system loud on some classical music from the Focal CDs we were confused to say the least, where is the sub? We can hear the tympani's and low notes crystal clear but it was a different experience overall from the other subs. It was very cool when we then dropped the level of the mid-bass and mids (Dayton RS100 and RS225s) and the sub revealed itself. It was there for sure, it was loud, it just didn't have the impact but the volume was for sure apparent. With my experience in car audio, the DIYMA was performing like a sub in to large of box. We were actually pushing high watts through it and it was moving quite a bit, and with our heads next to the driver (with the whole spectrum of music back at matched volume) we still couldn't feel an "impact". 

The SI Mag was a very great sound and i liked it a lot, especially when i kept reminding myself it was only 5" deep. It had a great mix of clarity and impact. The Tech n9ne song he mentions is supposed to sound like a machine gun, with VERY VERY VERY fast bass hits in a rapid fire sequence. This song really shows weakness in subs, but the MAG acted like oprah in a giant slingshot aimed at a brick wall; it moved with incredible force but stopped just when it was supposed to with sudden and sharp cutoff...in a good way. 

I like the terms people will label subs with to describe their tonal signature, impact, and overall character. I like to call my JVC Arsenal sub "a heavy foam pillow fight against hulk hogan" where it hits soft and thick but with lots of strength behind it. The MAG was a similar sound in my opinion to the JVC arsenal in terms of characteristics, but it felt a little sharper than most all of the subs tested here. I hope Josh and I can soon test the DIYMA again in a smaller box, and also i can steal his 8W7s.


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## Boostedrex (Apr 4, 2007)

ROFL @ the Oprah analogy!!!! That's killer! Thanks for chiming in Elvisjer. Your description of the DIYMA R12 also makes a lot more sense.


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## npdang (Jul 29, 2005)

Good review, although I don't find the results surprising given your stated preferences for SPL. There is simply no way a DIYMA can compete in that area, especially in the lowest frequencies where it may require 4 to 8x as much power to achieve the same output! 

I also agree with what everyone has said, that there are different subs designed for different purposes and listening preferences and rarely will you find a driver that satisfies everyone under every situation.

However as I've probably mentioned a dozen times in the past I hold a strong opinion that in a proper SQ setup a sub should neither be heard nor felt as a separate speaker, and therefore "impact" should be felt from the midbass and not the sub. Following along that note, when sub and midbass are properly tuned you can get very strong impact and complete transparency.

I would further support that statement by saying that at every DIYMA meet or anytime I audition my car to someone I have never been told that my bass lacked impact or output, but I have always been asked if I'm "running a sub."


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## SteveLPfreak (Sep 26, 2005)

npdang said:


> Good review, although I don't find the results surprising given your stated preferences for SPL. There is simply no way a DIYMA can compete in that area, especially in the lowest frequencies where it may require 4 to 8x as much power to achieve the same output!
> 
> I also agree with what everyone has said, that there are different subs designed for different purposes and listening preferences and rarely will you find a driver that satisfies everyone under every situation.
> 
> ...


I wonder if those commenting on impact don't run dedicated midbass drivers? The DIYMA 12 has plenty of output for me but I run dedicated 8's and my sub doesn't kick in until 63Hz.


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## npdang (Jul 29, 2005)

SteveLPfreak said:


> I wonder if those commenting on impact don't run dedicated midbass drivers? The DIYMA 12 has plenty of output for me but I run dedicated 8's and my sub doesn't kick in until 63Hz.


It's usually one of three things:

1. Weak midbass
2. Poor midbass to sub integration
3. They are looking for an exaggerated bass response between 30-60hz


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## thadman (Mar 1, 2006)

Electrodynamic said:


> I disagree thad though. Looking at both drivers on paper is only going to give you an idea about how each driver is going to perform but it won't tell you the whole story. Actually using your ears is a vital part of reviewing a loudspeaker. Afterall, it is our ears that are the critical part in our listening.


Why? We've already established that the modal behavior of the listening environment will dominate the frequency response, and obviously that is intrinsic to the bandwidth so it will affect all drivers considered equally assuming they are placed within the same location of the car. Any frequency response is achievable through equalization (for example, not enough low end? just use a linkwitz transform) Most of the variables that affect drivers higher in frequency don't apply, ie power response aberrations caused by the crossover/CTC spacing, power response aberrations caused by erratic behavior of the cone (nonpistonic motion), etc

What else would you suggest that would differentiate their performance besides waveform tracking (power compression), distortion profile, and SPL capability? All of those are able to be quantified without listening.


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## Electrodynamic (Nov 27, 2007)

thadman said:


> Why? We've already established that the modal behavior of the listening environment will dominate the frequency response, and obviously that is intrinsic to the bandwidth so it will affect all drivers considered equally assuming they are placed within the same location of the car. Any frequency response is achievable through equalization (for example, not enough low end? just use a linkwitz transform) Most of the variables that affect drivers higher in frequency don't apply, ie power response aberrations caused by the crossover/CTC spacing, power response aberrations caused by erratic behavior of the cone (nonpistonic motion), etc
> 
> What else would you suggest that would differentiate their performance besides waveform tracking (power compression), distortion profile, and SPL capability? All of those are able to be quantified without listening.


Why are our ears a critical part of our listening? Umm...it is the only way we hear sound. 

And sure, you can EQ the piss out of a subwoofer system to achieve the target bandwidth but you usually end up (especially if you're boosting any frequency) going beyond what the driver in question is comfortable reproducing on its own. I'm not saying that it will degrade the sound, but why boost down low when you shouldn't have to? 

On the note of the drivers high frequency reproduction _not_ coming into play - I highly disagree. It has been proven that inductance is essential to the transient response of the loudspeaker in question - irregardless of the pistonic (albeit linear or non-linear) behavior of the cone of said driver. See this paper on inductance (ie: high-frequency reproduction) and transient response of loudspeakers. As I mentioned, both drivers have extremely low inductances compared to almost all of the competition, so that should not be an issue. 

As I mentioned, the 'environment' that dictates the frequency response is fixed in Zach's, and this, review. As I've stated, the environment is the same (not Zach's and theRESONANCE's vehicles, but they are reviewing different speakers in the same environment. ...and in this case, the exact same enclosure, even though as I've stated before the DIYMA should have the upper hand in the 'SQ' dept as it has a much lower Qtc alignment being in 1 ft^3 sealed compared to the Mag v4. But as I've mentioned to other people before, if they can hear the difference of a .707 and .85 Qtc at 40 Hz (which is less than 1 dB) then they have a one in a million ear. It's also been stated by Zach and theRESONANCE that all of the reviews were done with the enclosures in the same positions and the drivers firing in the same direction. 

And if you would like to analyze which cone is more pistonic / linear within the target power application I will be more than happy to send a Mag v4 to whichever appropriate testing facility that can accurately measure and analyze the behavior of the Mag v4's cone vs. the DIYMA's.


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## thadman (Mar 1, 2006)

Electrodynamic said:


> Why are our ears a critical part of our listening? Umm...it is the only way we hear sound.
> 
> And sure, you can EQ the piss out of a subwoofer system to achieve the target bandwidth but you usually end up (especially if you're boosting any frequency) going beyond what the driver in question is comfortable reproducing on its own. I'm not saying that it will degrade the sound, but why boost down low when you shouldn't have to?


On the subject of drivers, I'm well aware that different mechanical parameters will yield different frequency response curves and that equalizing them to produce similar transfer functions will most likely lead to serious compression if it is anything but minimum. That is very fundamental compared to what we are discussing. What I was establishing was that the frequency responses for subwoofers were predictable. You can model them and they should measure very close to the predicted curve (assuming the input parameters were accurate and that the measurement environment was anechoic), so it should come as no surprise to members of this board that a particular woofer will be more efficient over another woofer over a particular bandwidth. The resonant behavior of the "system (air, motor, suspension, moving mass)" dictates the frequency response at low frequencies, while the cones behavior dictates the frequency response at high frequencies. With midrange drivers you have modal behavior in the cone, surround resonances, etc that require extremely complex modeling programs (FEA analysis) to determine their frequency response and total radiated energy. This is not very accessible to consumers due to the high cost and learning curve required for such software. You've got to remember that the resonances create constructive and destructive interference patterns that do not radiate equally on as well as off-axis...this is extremely hard to determine and leads to a drivers "signature" as this phenomenon is not adequately portrayed by a frequency response done on a single point in space. Luckily the cones are usually pistonic in the LF region and regardless any flexing motion of the cone would not place any point of the surface of the cone in a position to contribute destructive interference with another point. The ambiguity of a speakers sound that plagues midrange drivers does not necessarily apply to low frequency drivers. With this information we can know how the subwoofer will perform in a vehicle, without having to take measurements. If you want a woofer with a certain frequency response (ie biased lower bass, biased upper bass, etc) buy the one that models accordingly. This is simple, a consumer can perform the research themselves very easily.



Electrodynamic said:


> On the note of the drivers high frequency reproduction _not_ coming into play - I highly disagree. It has been proven that inductance is essential to the transient response of the loudspeaker in question - irregardless of the pistonic (albeit linear or non-linear) behavior of the cone of said driver. See this paper on inductance (ie: high-frequency reproduction) and transient response of loudspeakers. As I mentioned, both drivers have extremely low inductances compared to almost all of the competition, so that should not be an issue.


Why are you bringing up Inductance, you as well as I already knew the answer to your own question. Inductance is adequately low for both drivers over the bandwidth we are discussing, thus it is a variable that need not be considered for this particular comparison...a point that was already established.



Electrodynamic said:


> As I mentioned, the 'environment' that dictates the frequency response is fixed in Zach's, and this, review. As I've stated, the environment is the same (not Zach's and theRESONANCE's vehicles, but they are reviewing different speakers in the same environment. ...and in this case, the exact same enclosure, even though as I've stated before the DIYMA should have the upper hand in the 'SQ' dept as it has a much lower Qtc alignment being in 1 ft^3 sealed compared to the Mag v4. But as I've mentioned to other people before, if they can hear the difference of a .707 and .85 Qtc at 40 Hz (which is less than 1 dB) then they have a one in a million ear. It's also been stated by Zach and theRESONANCE that all of the reviews were done with the enclosures in the same positions and the drivers firing in the same direction.


You are correct in that the environment is the same, but failed to acknowledge its effects on sound quality that may lead to false impressions about the drivers. For example, lets say you have an environment with significant cabin gain. A woofer with a shallower rolloff will have a biased lower bass response and may appear slow and bloated while a woofer with a sharper rolloff may have a flatter and more accurate frequency response. While in a different environment that offers little cabin gain, the woofer with the shallower rolloff will have a flatter and more accurate frequency response while the woofer with the sharper rolloff will have a biased upper bass response and may appear to have "slam" or sound "thin". This is why the ear is a very poor way to test drivers, assuming you want the drivers performance adequately represented. By having them tested in separate vehicles you are establishing that a single woofer will work in all vehicles, and this couldn't be farther from the truth. The frequency response (woofer choice, box design) should compliment the cabin gain of the vehicle for the most accurate response as this maximizes efficiency and optimizes its performance. No single woofer is the answer for every vehicle due to the nature of the bandwidth involved. It depends highly on the application.

Waveform tracking, distortion profile, and SPL capability should thus be the parameters considered to distinguish the performance between two woofers because these are the parameters that are consistent between installations and the research involved to determine the frequency response of a particular driver that offers a complimentary curve is very elementary and easily accessible to consumers....this assumes the consumer is interested in making an accurate decision based on his purchase.



Electrodynamic said:


> And if you would like to analyze which cone is more pistonic / linear within the target power application I will be more than happy to send a Mag v4 to whichever appropriate testing facility that can accurately measure and analyze the behavior of the Mag v4's cone vs. the DIYMA's.


This will not be necessary, we've already established that both woofers should be pistonic assuming they are operated within the LF bandwidth. I understand that you don't want ambiguity regarding the capabilities of the woofer created and certainly not bad press, the purpose of my post was to educate the members of this forum on the limits imposed by the type of testing that was undertaken on both woofers, not to provide confusion. So that they may understand that what one member experienced may not apply to their particular application. I assure you that I am certainly not questioning your drivers capabilities, as it appears your Mag is an extremely well engineered subwoofer driver. Nor am I questioning your ability or desire to provide the information necessary to make an informed decision on a subwoofer purchase, as you have so demonstrated by your willingness to have whatever tests done that are necessary to providing a clear picture of the Mags performance. I applaud you for being a responsible and honest businessman.


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## SteveLPfreak (Sep 26, 2005)

npdang said:


> It's usually one of three things:
> 
> 1. Weak midbass
> 2. Poor midbass to sub integration
> 3. They are looking for an exaggerated bass response between 30-60hz



Exactly. And I would have to say, IMHO, that #3 is the big one. Most want the exaggerated low end and have become accustomed to that sound.


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## bassfromspace (Jun 28, 2016)

SteveLPfreak said:


> Exactly. And I would have to say, IMHO, that #3 is the big one. Most want the exaggerated low end and have become accustomed to that sound.


 Which is the reason you see drivers such as the sw300 and peerless xls drivers recommended over superior subs such as the w7 etc. Midbass is the devil.


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## Boostedrex (Apr 4, 2007)

bassfromspace said:


> Which is the reason you see drivers such as the sw300 and peerless xls drivers recommended over superior subs such as the w7 etc. Midbass is the devil.


Superior subs like the W7 huh? That's funny. 

Nick, I think Paul and I figured out the oddity with out testing. The xB was a ton of cabin gain. That coupled with my limited EQ (nothing below 50Hz) is why we are getting the results that we are getting. Just like Thadman mentioned, the Mag has a MUCH more shallow roll off than the DIYMA. So the shallow roll off + my cabin gain is causing the issues we are seeing between the 2 subs. Now I need to find someone with a car with minimal cabin gain and see how they compare.

Zach


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## bassfromspace (Jun 28, 2016)

Boostedrex said:


> Superior subs like the W7 huh? That's funny.
> 
> Nick, I think Paul and I figured out the oddity with out testing. The xB was a ton of cabin gain. That coupled with my limited EQ (nothing below 50Hz) is why we are getting the results that we are getting. Just like Thadman mentioned, the Mag has a MUCH more shallow roll off than the DIYMA. So the shallow roll off + my cabin gain is causing the issues we are seeing between the 2 subs. Now I need to find someone with a car with minimal cabin gain and see how they compare.
> 
> Zach


Did I miss out on the joke?


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## Boostedrex (Apr 4, 2007)

bassfromspace said:


> Did I miss out on the joke?


I doubt it. While the W7 is a very well engineered driver, it is grossly overpriced seeing as how long ago it was released. I would also highly doubt that it would measure any better than either of the subs being discussed in this thread. And I'd be willing to bet that it wouldn't be any better of a candidate than the Mag or DIYMA in an SQ setup. Not saying it's a bad sub at all, but the W7 goes into the same category as the IDMax IMHO which is an over priced and over hyped sub.


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## thadman (Mar 1, 2006)

Boostedrex said:


> Superior subs like the W7 huh? That's funny.
> 
> Nick, I think Paul and I figured out the oddity with out testing. The xB was a ton of cabin gain. That coupled with my limited EQ (nothing below 50Hz) is why we are getting the results that we are getting. Just like Thadman mentioned, the Mag has a MUCH more shallow roll off than the DIYMA. So the shallow roll off + my cabin gain is causing the issues we are seeing between the 2 subs. Now I need to find someone with a car with minimal cabin gain and see how they compare.
> 
> Zach


What will testing it in a vehicle with less cabin gain substantiate? You've already established the differences between them in terms of frequency response (ie Mag has a shallower rolloff). Testing them in another vehicle will only lead to a predictably different response that favors the other driver. You know this. There is no best driver, remember you are designing a "system" that involves variables other than the driver considered so there can't be a "best". It depends highly on the application, you will not reach a conclusion of Woofer X > Woofer Y by conducting what you've suggested...only Woofer X > Woofer Y for a particular application which in your case involves a driver with a sharper rolloff to compensate for the significant cabin gain provided by the xB.


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## Boostedrex (Apr 4, 2007)

thadman said:


> What will testing it in a vehicle with less cabin gain substantiate? You've already established the differences between them in terms of frequency response (ie Mag has a shallower rolloff). Testing them in another vehicle will only lead to a predictably different response that favors the other driver. You know this. There is no best driver, remember you are designing a "system" that involves variables other than the driver considered so there can't be a "best". It depends highly on the application, you will not reach a conclusion of Woofer X > Woofer Y by conducting what you've suggested...only Woofer X > Woofer Y for a particular application which in your case involves a driver with a sharper rolloff to compensate for the significant cabin gain provided by the xB.


I'm sorry, I must have not worded my previous post correctly. I meant that I'd like to listen to the Mag in a vehicle with less cabin gain so that I can hear the sub in an environment better suited to it's response. I've figured out that it isn't the right driver for my application, but it's still a wonderful driver. So I'd like to find an application where it would truly excel. It's going to end up in my convertible RX-7 install coming up late this year. That car has zero cabin gain, so the Mag should be the ideal choice for it. 

Zach


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## bassfromspace (Jun 28, 2016)

Boostedrex said:


> I doubt it. While the W7 is a very well engineered driver, it is grossly overpriced seeing as how long ago it was released. I would also highly doubt that it would measure any better than either of the subs being discussed in this thread. And I'd be willing to bet that it wouldn't be any better of a candidate than the Mag or DIYMA in an SQ setup. Not saying it's a bad sub at all, but the W7 goes into the same category as the IDMax IMHO which is an over priced and over hyped sub.


I didn't want to jack the thread, but a few comments.

1.I agree that the w7 is pricey even after all this time on the market. Some would look at that as a testament to the strength of it's design, however. Many of it's contemporaries at the time are no longer around including tc sounds, audiomobile, and adire. The w7-based home subs for JL have been winning major accolades since their debut.

2.The w7 will cleanly outdisplace the seas, mag, and r12. It will also measure better than either sub in distortion, power compression, or linearity. 

3.After carsound tested the w7, dan wiggins even stated the 7 was superior to the brahma (although he attributed that to more R&D funds available to JL). The 7 is also one of NPDang's favorite subs. Also, Mark Eldridge uses a jl home sub in his reference system used for his seminars. That's pretty good company,IMO.

I'm not sure why you picked that comment out being that we were discussing midbass and system integration and I was stating my opinion.

Sorry for the interruption. Back on topic.


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## thadman (Mar 1, 2006)

bassfromspace said:


> 2.The w7 will cleanly outdisplace the seas, mag, and r12. It will also measure better than either sub in distortion, power compression, or linearity.


Do you have any credible sources outlining the measurements completed and the conditions operated under to substantiate those claims? I don't believe the Mag has been Klippel tested yet so I fail to see how you would be able to make an educated and informed comparison of the two drivers.


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## bassfromspace (Jun 28, 2016)

thadman said:


> Do you have any credible sources outlining the measurements completed and the conditions operated under to substantiate those claims? I don't believe the Mag has been Klippel tested yet so I fail to see how you would be able to make an educated and informed comparison of the two drivers.


I don't actually, but based on previous XBL^2 designs, I'd feel safe putting my money where my mouth is.


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## thadman (Mar 1, 2006)

bassfromspace said:


> I don't actually, but based on previous XBL^2 designs, I'd feel safe putting my money where my mouth is.


FYI, while the Mag is XBL^2, the DIYMA is not. You are making quite an audacious claim based solely on assumptions. Misinformation is a cyst to this forum because it creates confusion and may lead to false impressions or unrealistic expectations of a drivers capabilities. It is combating exactly what we are trying to achieve...accurate, easily accessible, objective information regarding a drivers performance that users of this forum can use to determine if its optimal for their particular application or not.


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## Ziggy (Nov 29, 2007)

Well... I just got my Mag in a few minutes ago... lots of fondling right now (you know how that goes!)... drop a pic in later when it gets uploaded... 
Then I'll try some tests of my own.... Bitches!


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## npdang (Jul 29, 2005)

Let me sum up everything I'm about to say sucinctly... there is no such thing as a universally BEST driver!

What is going to be considered "best" is going to depend on a host of factors such as power available, listening preferences, budget, etc. In other words it will be HIGHLY application specific, and the best driver will be the one that "best" fits the intended application. 

For example let's just compare the W7 and the DIYMA. Obviously, the W7 will have better distortion performance at high output, greater output capability, and a stronger low end sensitivity. It's greatest strength IMHO though is it's ability to play near it's peak output capability with a minimum of mechanical noise. I can't think of a better driver for someone wanting high output, low distortion, and low noise. However, how many of us really need/use all of that? And what are the compromises in doing so?

For example someone looking at a mostly SQ setup consisting of a more accurate bass reproduction at realistic listening levels, the DIYMA in many cases would offer a flatter "out of box" response requiring less tuning and setup, as well as similar levels of distortion performance, and do it for less money and in a much smaller box.

And along those same lines, I feel that a more useful and informative review would not be a blanket comparison declaring some "winner", but rather an explanation of the strengths and best applications for each driver.

On a side note, I don't believe that "cone" behavior plays any significant or even marginal role in the SQ of a sub. I also don't think that final system Q per se is of any value. IMHO, really the only strong indicator of SQ is how well the final system response (sub, processing, listening environment together) matches the listener's preferred target response and does not deviate from that response with a change in output (non-linear distortion, bl/thermal compression, mechanical noise).

On the issue of inductance in subs... again not an issue IMHO. Low inductance sub will save you some eq'ing and frustration if you don't know how to tune, but you're fooling yourself if you think even the worst sub out there can't play to at least 1khz or so flat directly on axis. The biggest issue with upper end response of a sub in car is going to be the rear seats ... which in my experience tend to act as a first or second order lowpass filter at 80-120hz depending on how thick the metal is back there and the direction of the sub.


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## npdang (Jul 29, 2005)

bassfromspace said:


> I didn't want to jack the thread, but a few comments.
> 
> 1.I agree that the w7 is pricey even after all this time on the market. Some would look at that as a testament to the strength of it's design, however. Many of it's contemporaries at the time are no longer around including tc sounds, audiomobile, and adire. The w7-based home subs for JL have been winning major accolades since their debut.
> 
> ...


I believe DW only conceeded that the W7 had a quieter, longer stroke basket/suspension design. In many other respects including manufacturing costs, motor topology, and inductance among others, I think DW would still consider the Brahma to be a superior driver.


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## bassfromspace (Jun 28, 2016)

thadman said:


> FYI, while the Mag is XBL^2, the DIYMA is not. You are making quite an audacious claim based solely on assumptions. Misinformation is a cyst to this forum because it creates confusion and may lead to false impressions or unrealistic expectations of a drivers capabilities. It is combating exactly what we are trying to achieve...accurate, easily accessible, objective information regarding a drivers performance that users of this forum can use to determine if its optimal for their particular application or not.


Thad,

I understand where you're coming from but, I'm simply giving my opinion, not stating an objective fact. There's nothing else to be read into that statement. If someone does, they're on their own.


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## theRESONANCE (Aug 28, 2008)

*Condensation*.. Don't worry guys i didn't bathe with my sub.


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## bassfromspace (Jun 28, 2016)

npdang said:


> I believe DW only conceeded that the W7 had a quieter, longer stroke basket/suspension design. In many other respects including manufacturing costs, motor topology, and inductance among others, I think DW would still consider the Brahma to be a superior driver.


I can't quote him directly because this was long ago, but Dan was alluding to the fact that the w7 wasn't better because of any physical aspects but more because JL has a bigger R&D budget. I'm sorry I didn't clarify that earlier.

Here's a huge thread from 2002 where the Brahma and w7 were both tested by Richard Clark:


Richard Clark/Brahma......your thoughts - Page 11 - CARSOUND.COM Forum

These were the heyday's of car audio. Oh, how I miss them.


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## DanWiggins (Jun 15, 2005)

npdang said:


> I believe DW only conceeded that the W7 had a quieter, longer stroke basket/suspension design. In many other respects including manufacturing costs, motor topology, and inductance among others, I think DW would still consider the Brahma to be a superior driver.


Yes, that would be correct.


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## Electrodynamic (Nov 27, 2007)

Keep in mind that the reviewee was referencing an 8W7, not a 12W7. That might be kind of important to the numbers junkies lingering in this thread, which is still distracting from the main point of this thread: it is a REVIEW, not an test that goes more in-depth than a Klippel allows. Using your ears has never been such taboo.


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## npdang (Jul 29, 2005)

Electrodynamic said:


> Keep in mind that the reviewee was referencing an 8W7, not a 12W7. That might be kind of important to the numbers junkies lingering in this thread, which is still distracting from the main point of this thread: it is a REVIEW, not an test that goes more in-depth than a Klippel allows. Using your ears has never been such taboo.


Agreed, sorry to go so off topic! It can be hard for some of us to resist sometimes.


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## bassfromspace (Jun 28, 2016)

DanWiggins said:


> Yes, that would be correct.


I apologize for the error.


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## bassfromspace (Jun 28, 2016)

Electrodynamic said:


> Keep in mind that the reviewee was referencing an 8W7, not a 12W7. That might be kind of important to the numbers junkies lingering in this thread, which is still distracting from the main point of this thread: it is a REVIEW, not an test that goes more in-depth than a Klippel allows. Using your ears has never been such taboo.


Sorry Nick. 

It started with the midbass integration issue and got off topic.


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## wdemetrius1 (Aug 16, 2007)

I'm curious to know how would the mag perform in a smaller enclosure considering that it is a shallow mount sub or is 1cu ft the ideal size?


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## gsr22 (Jul 30, 2007)

wdemetrius1 said:


> I'm curious to know how would the mag perform in a smaller enclosure considering that it is a shallow mount sub or is 1cu ft the ideal size?[/QUOT
> 
> 1 cube is the recommended size even says so on the packaging lol


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## quality_sound (Dec 25, 2005)

And it definitely needs a larger box.


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## elvisjer (May 13, 2008)

IMHO, i would want shallow mount subs to NOT need a large box. I know that it makes it easier to do different box shapes, but it seems it would be more logical to not require a huge box as well.


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## quality_sound (Dec 25, 2005)

The Mag isn't exactly a shallow mount. It's not a WGTi by any stretch of the imagination but it's not a BM either.


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## subwoofery (Nov 9, 2008)

Having small box for shallow woofers is just logical. Can't believe some manufacturers released shallow tens that need 1cuft box to sound good. 

TW5, SI Mag, SI BM, Soundstream Stealth-13, eD SQ10 (why did I put that one in???) are one of the few that require small boxes.


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## gsr22 (Jul 30, 2007)

quality_sound said:


> And it definitely needs a larger box.


what size box do you feel works best? power dependent?


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## quality_sound (Dec 25, 2005)

subwoofery said:


> Having small box for shallow woofers is just logical. Can't believe some manufacturers released shallow tens that need 1cuft box to sound good.
> 
> TW5, SI Mag, SI BM, Soundstream Stealth-13, eD SQ10 (why did I put that one in???) are one of the few that require small boxes.


I don't know if I'd call the Mag a small box sub. 1ft^3 isn't huge but it's not super small either. It's definitely better than a lot of other subs out though. You left out the DIYMA R12. 



gsr22 said:


> what size box do you feel works best? power dependent?


I liked the stuffed .85ft^3 box.


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## Electrodynamic (Nov 27, 2007)

I think it's a small box subwoofer. When compared to its competition it's shallower, which allows for more flexible installation options, and it is substantially lighter than its competition. 0.85 (stuffed) to 1 ft^3 dead-even doesn't make it a large box subwoofer IMO. Maybe I'm just way off kilter though.


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## wdemetrius1 (Aug 16, 2007)

Are there any shallow mount subs that sound good in a smaller enclosure? I think that this would make a good shootout tread.


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## quality_sound (Dec 25, 2005)

Electrodynamic said:


> I think it's a small box subwoofer. When compared to its competition it's shallower, which allows for more flexible installation options, and it is substantially lighter than its competition. 0.85 (stuffed) to 1 ft^3 dead-even doesn't make it a large box subwoofer IMO. Maybe I'm just way off kilter though.


Like I said...it's not a huge box but IMO a true small box 12" is in the .5-.75ft^3 range. 

And I said small BOX category, not small FRAME category. Yes, the size of the Mag is a HUGE plus because you can put it into a lot of places that a lot of other subs physically won't fit in.


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## npdang (Jul 29, 2005)

You guys are crazy... the smallest enclosure is NO enclosure


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## mvw2 (Oct 2, 2005)

Win! 

But yeah.

What do you tell anybody whining about trunk space that wants subs?


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## Ziggy (Nov 29, 2007)

I plan on throwing the Mag in my downfiring center console that "unprediactable" made for me... 
Said it was 1.2 cubes for the 13oV2... The Mag should displace less space inside than the Ov -SO mabey I'll be around 1.3 cubes...


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## Boostedrex (Apr 4, 2007)

Ziggy said:


> I plan on throwing the Mag in my downfiring center console that "unprediactable" made for me...
> Said it was 1.2 cubes for the 13oV2... The Mag should displace less space inside than the Ov -SO mabey I'll be around 1.3 cubes...


That's gonna be a GREAT box for the Mag IMHO. Is your truck a single cab or extended/crew cab?


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## Ziggy (Nov 29, 2007)

Extra cab... with the half rear suicide doors... Funny how I like to listen to it with my front doors open while sitting on the tailgate -but that makes it hard to drive.


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## Boostedrex (Apr 4, 2007)

I know this is extra work, but if you don't mind Ziggy try running the Mag both at 4 ohms and at 1 ohm. The more I've experimented with this, the more I realize what Patrick (Zuki) has been telling me. I will always run my speakers at the highest impedance possible in my setups from now on.


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