# Issue w/ TC2K?



## MadMaxSE-L (Oct 19, 2006)

So info on these subs subs is just about nill - seems to have all dried up years ago. It doesn't look like anyone is using these anymore for some reason...

Anyway, I have 2 of them and was thinking about putting both in my 97 Maxima. I have 2 Eclipse XA4000 amps, so each sub would be getting about 750w rms(admittedly not enough); however, I think I want to do a vented box sicne when I had 1 tc in there in a 1^ft seald(tc specs for SQ) box w/ 1 XA4000, the results were less than spectacular...

When I first got the first TC, I put it in a ~2^ft box just to test it with 1 xa, and there was hardly any output at all. Box was waaaay too big. If I did sealed again, I was thinking about trying ~1.25^ft/sub. Maybe having 2 in there would get me the output I need.

If I went vented, I was thinking maybe 2^ft/sub, tuned to around 28hz. I'm not too concerned with trunk space or anything, but I don't have a whole lot. I can get about 4^ft if I put the subs in the box backwards...

I was basically looking for anyone who had experience with these drivers to let me pick their brain. I really like these subs and amps for some reason, but I don't want to be disappointed again. I'm familiar with box building/designing but for some reason these things model weird so I am looking for real-world advice please.

By "modeling weird", I meant that in winISD, optimal sealed box seems to be 0.442^ft, and optimal vented looks to be 0.675^ft tuned to ~30hz. Now I realize these do not take into account cabin gain, but I just can't imagine building a vented box less than 1^ft and having it sound good. I used the specs below from Subguts - and from the other info I have on the TC2K's, they look to be correct. The specs in bold are the only ones I put in WinISD, so maybe I messed something up...

100 Newtons2/watt Motor Force
*800 Watts Sustained Power*
3" Anodized Aluminum Voice Coil
Single Dish Aluminum Cone
1" Wide NBR Surround
190 Ounce Magnet Structure
*28mm XMax*
10" Diameter Suspension System
Custom Cast Aluminum Frame
Quick-Detach Top Assembly
12" TC-2000
*Qts 0.264
Qes 0.284
Qms 3.72*
*Fs 20hz*
Res 3.12Ω
Ls 2.41mH
Lp 5.62mH
Rp 4.86Ω
*Dia 240mm*
*Vas 77.3l*
mms 265g
cms 228.5um/N
*bl 17.2T*m*
*Spl 85.5dB*

So when I see all these TC's in boxes ranging from 2-4^ft it confuses the hell out of me. The one I have in a 1^ft sealed box sounds ok but the output just isn't there - I don't really think putting it in a vented box almost half that volume is going to get me there either though...


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## Hispls (Mar 12, 2008)

Sealed box isn't going to do "output" for you. These subs really need ported alignment. A friend of mine in Georgia had a pair of 12" 2K's that he tried sealed and was very disappointed....after going ported, he was blown away.

I haven't even tested mine sealed yet, but I can tell you ported is very good. 

Running the 15", I can say that a 4" cube box tuned @27hz ish is very nice and linear and will play with authority to about 18hz.

I'm squeezing mine in a smaller box now 2.5" ish per sub and tuning 34hz ish and I lose a lot of the very low end. It does have a bit more punch but is more peaky. I'm going to try to re-build my box this year and get more volume as I found overall I lost a bit of output with the larger box, but the linearity and ability to really do it at 20hz was worth the tradeoff. (I play a lot of movies and do use ultra low material).

I can also tell you that they'll handle 1200W continuous for as long as you can stand it. They'll get warm, but I didn't have any problems. I'm currently running 1800-2000 per sub now and they will smell funny pretty fast if I try to give them all of that.

I also have the TS parameters from the old TC line here (I downloaded it while it was still around on their site).


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## cubdenno (Nov 10, 2007)

I agree with ported designs for the TCs. I bought a design from PWK using a single reflex bandpass for my 15. Amazing sound down into the 20s due to transfer function. it measures flat 70-30 in car. Porting low in a car is in my opinion silly. If output is what you want the lowest I would tune is 35 hertz. 40 is about the best for low extension and output.I built a ported enclosure with the ability to bolt on extensions to tune it lower and to seal it up.I found that tuning ultra low kills a lot of output in the upper bass that a slightly higher tuning freq will add extra kick you can feel in your chest and ruffle your hair. If you are going to play movies in your car or play some crazy music with ultra low material then port low or go sealed. But if you are not popping in Telarc cd's or movies, port a bit higher. Those TC woofs will belt it out.


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## MadMaxSE-L (Oct 19, 2006)

Since they'll be going in my car, I don't really think I'll need extension down to 20hz - I was thinking maybe tuning the box to around 35 and letting cabin gain help reinforce the low-end. I definately want to be able to hit the lows, but I also like the punch I get from my current Earthquake DBX-12's in a ported box tuned to about 32hz.

I think what I am going to do is put one of my TC2Ks in one side of my current ported box that I have my Earthquakes in - that will give it about 1.625^ft tuned to about 32 hz. Hopefully that will give me a good idea of where I'm at as far as output and FS. From the modeling though it just looks like way too much box though...


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## MadMaxSE-L (Oct 19, 2006)

cubdenno said:


> I agree with ported designs for the TCs. I bought a design from PWK using a single reflex bandpass for my 15. Amazing sound down into the 20s due to transfer function. it measures flat 70-30 in car. Porting low in a car is in my opinion silly. If output is what you want the lowest I would tune is 35 hertz. 40 is about the best for low extension and output.I built a ported enclosure with the ability to bolt on extensions to tune it lower and to seal it up.I found that tuning ultra low kills a lot of output in the upper bass that a slightly higher tuning freq will add extra kick you can feel in your chest and ruffle your hair. If you are going to play movies in your car or play some crazy music with ultra low material then port low or go sealed. But if you are not popping in Telarc cd's or movies, port a bit higher. Those TC woofs will belt it out.


Yeah - I think we were typing the same thing at the same time. I think that cabin gain will help me keep my low end, which will IMHO enable me to tune higher and get more output. 

Sometimes I do listen to rap when I want to stretch my system out, so I would like it to be able to reach down to ~30hz if necessary. I don't want to have to hp my subs @38hz after the box quits and loose any of my shake


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## cubdenno (Nov 10, 2007)

I have the subsonic on mine set at 25 hertz and that is a bit to high really. I ran the 2K through WinISD and 1.6 will be fine. Throw the highpass at 20 hertz or a bit lower and call it a day. The smaller box, even ported increases power handling but lowers efficiency. Make the box bigger and you gain output with the same power. With ported make sure you don't choke the woofer with a small port. I did that already. Give it at least 12-16 square inches of area per cubic foot of volume. And it will fookin shine!! sent a PM


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## Hispls (Mar 12, 2008)

At a second glance, the 12's model quite differently than the 15's. I did dig up my friend's install log. 

Car Audio Message Forum - CarStereo.com

The first box (sealed) lacked a bit of output. The second ported would make his rear door flex to the point where the wiper blade slapping the glass became obnoxious.

Unfortunately, he didn't write details, but looks like (and as I recall) appx 1.25-1.5 cube per sub and mid 30's tuning. 

Agreed about the higher tuning with the 12's. No need to tune below 30hz period, and as high as 40 looks like it isn't too peaky. The 15's really want much more box and lower tuning or response is peaky and really lacking <30hz (even with cabin gain). 

Anyway, report back on this.


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## MadMaxSE-L (Oct 19, 2006)

OK - checked the coils yesterday and they both measured out at ~3.15 ohms, so I am good there.* I also fixed my problem*...

I have heard conflicting reports that the TC2000 models like small sealed boxes, and I have also heard they like large ported boxes - so what the hell I was extremely disappointed with the output from this sub while it was in the 1^ft sealed box that I built for it. So much so, that I took it out and put my Earthquake DBX-12's back in my Maxima, in the vented box I made for them that gives each 12" 1.625^ft after port/brace/driver displacement, tuned to about 33hz. 

Yesterday, I decided to throw my TC2k in one side of that box to see what was up, and holy $h!t am I glad I did! I now have a bridged channel of one XA4000 going to each coil of the TC(about 700wrms), and I am very, very impressed with my decision. So much so, that I removed my other Earthquake DBX-12 amd put both of them in my wife's car in a sealed box for her

In the end, I think I simply do not have the power right now to push these things in that small of a sealed box, but they have more than enough "snap" for me in the vented box. And might I add - these things will dig loooooowww....

I can't wait for my other one to get here!


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## cubdenno (Nov 10, 2007)

Congrats man!! Glad the box changed worked. I figured it would


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## MadMaxSE-L (Oct 19, 2006)

cubdenno said:


> Congrats man!! Glad the box changed worked. I figured it would


Man did it ever. I think I am going to have to do some sheetmetal reinforcement after I get the other one...

I really appreciate the help too


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## Hispls (Mar 12, 2008)

Glad that worked out. Sounds like my friend who also was blown away after he went ported with his.


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## MadMaxSE-L (Oct 19, 2006)

Hispls said:


> Glad that worked out. Sounds like my friend who also was blown away after he went ported with his.


Yeah - IMHO ported is definately the way to go with these subs. Now I think I just have to find out a way to get a wider port opening for these things. I think with only a 2" opening I will be loosing some output there as well. Each port is already ~27" long, so I think if I build another box I am going to tune a little higher so I can go wider on the port and keep the same length...


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## Hispls (Mar 12, 2008)

If you're using round ports, adding another port the same length may tune 5hz higher.


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## MadMaxSE-L (Oct 19, 2006)

Hispls said:


> If you're using round ports, adding another port the same length may tune 5hz higher.


I've been using slotted ports, but when I build another box I think I am going to use round...


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## cubdenno (Nov 10, 2007)

I think slotted is easier. The frequency is determined by port area and length for a given enclosure volume. So say you have a 2 cubic foot enclosure and you want 40 hertz,

4 inch port round--12.57 in sq of area
You need the port 7.61 inches in length

Slotted port 1.04 inches wide by 12 inches high----12.57 in sq of port area
you need it 7.61 inches in length

Sorry about the strange width. Was to just illustrate the same area.

SPL guys say the rule of thumb for ports is 12-16 sq in of port area per cubic foot of enclosure. Now this is of course dependent on the woofer and it's potential displacement. With your TC, use a lot of port area. it made a difference for me. In my "boom" enclosure its 5 inches wide by 16 high and long. hell, the port volume is half the dam box.


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## Hispls (Mar 12, 2008)

I opted for round ports in my most recent build just because I have a plumber friend that hooks me up with PVC pieces. I put a screw piece on one of the ports so I can close it up and tune higher if I like. The way it worked out closing up the fourth port tunes 5hz lower which is slightly more desireable for my movie watching. When I rebuild this summer I'll probalby do slot port again for more area and ease of implementation.


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