95Honda

No problem. Glad it worked out for you. -Mike

PM me your phone number.

Are you going to try both subs in the exact same box or are you going to try them in the same alignment?

You can kill that sub with that amp. Don't send more than 900 watts to it in your box. There isn't a single person on here (so far) who has completed an objective power measurement on this amp (and no, clamping the amp in your car with a sub hooked up is NOT objective), so all of this "doesn't make rated power" BS is all heresay... Don't pay attention to it all...

Well, yes, that makes all the difference.... With that box and tuning, anything near 1000 watts will more than likely damage the woofer a few Hz below tuning and anywhere in the 40-60Hz region. So plan on a SSF and limit yourself (you really have to do this on your own!) to around 900 watts. If you are worried you can't limit the power to 900 watts, buy a less poweful amp and don't overdrive it, or buy a 450 watt amp and do whatever you want and not hurt anything.... And be almost just as loud....

It all depends on the box. And no matter where the gain is set, you can get full power out of that amp.....

Additionally, nobody knows what the "rated" power is of that amp, Hifonics doesn't list it. All they say is 2600 watts RMS. This doesn't mean anything. It could be rated at 10% THD for all we know, and in that case, it probably makes it's "rated" power. Again, tough to say with this kind of amplifier and advertising...

You won't see many, if any objective power measurements on this or any other car audio site. If anyone measures the power output while in a car and hooked up to a speaker, it is meaningless. It puts out what it should for the price...

Is this a joke? Seriously, you need to read those white papers and go through Martin Kings site before you waste more time or damage your drivers. They spell everything out. Especially the kind of line dampening to use. This is absolutely NOT how you dampen a T-line...

Download WINISD or Boxplot 2.0 Run the numbers, then double check back on the site with your results. You'll never figure out how to do any of this if you don't attempt some on your own... Also, don't use particle board... Ever... It really sucks both acoustically and structurally....

The T/S are done with small signal analysis. It won't change them to measure the coils in parallel.

Should be fine.

You'll notice, I am one of the only people who has consistently said the opposite... Also, I have always stated the opposite.... Additionally, a driver like the BTL (in the correct alignment) will always produce more SPL at any given voltage than an innefficient alignment such as Bob's little sub... I have always seen the direct proportionality of Le to back EMF. You traditionally see drivers with permable core metals, shorting rings and short voice coils have lower Le and Back EMF. I completely understand what back EMF (voltage) is and why it is produced. I know how an armeture works. I also understand what makes it worse. I also know what mittigates the problems associated with it, and what exaggerates the problems... You don't have to agree with me, that is why this is a forum. We aren't arguing either, we have different points on this. Don't take it personally...

Read the white paper(s). 30Hz? Shoot for 5-6ft stuffed. Finish at Sd. Start at 1.25x Sd. That's a T-line... If you aren't stuffing, it needs to be alot longer than that (A LOT longer), that is why ALL proper T-lines are stuffed.... T-Lines ARE NOT for SPL, there are NOT as efficient as a ported enclosure above resonance....

The gain setting will not limit your amplifier output, you still could be using every watt that amp will make... The sound difference between sealed and ported is non-existant assuming both are aligned properly. A ported box has the potential to have more output for an octave or so below tuning vs a sealed box below resonance. As far as sound quality, you'll have about a 1000 opinions, and none of them really matter. You have to try and hear it for yourself....

How much are those?

Were both lines on each side of the woofer the exact same length? If they were, they were cancelling each other within the pass band of the line... I didn't realize until I saw the last pictures what you were actually doing.... You had 2 identical outputs, about 1' from each other 180 degrees out of phase.... Not a good thing for much below 80Hz or so..... Trying building a straight forward 1/4 wave stuffed line.... Then you will hear what a T-line is supposed to sound like... You'll lose alot of efficency making a bandpass with a T-line on one side vs. a standard port do to line loss...

Here is a link to a big carpeted build I did a while ago- http://www.forceaudio.com/showthread.php?t=201&page=4

Don't ask questions on a car audio board about 1/4 wave line length.... Table 1 here gives you line length: http://www.quarter-wave.com/TLs/Alignment_Tables.pdf Notice driver Fs and bass boost aren't part of it. Seriously, if you are interested in T-lines, read this entire document....

It doesn't matter where you set your gains with a 5000 watt amp, you can still get well over 5000 watts..... There is no minimum power for any sub. Period. The more power you have the louder they will play with more non-linearities. The less power you have the less louder they will play with less non-linearities. The power required to get full output from any subwoofer is box alignment dependant and has nothing whatsover to do with the RMS rating...

Nothing to do with either. The length determains the cutoff, that's it... Read up on Martin Kings (www.quarter-wave.com) white papers, you'll save yourself alot of time and headache. Additionally, diysubwoofers.org has a short, yet to the point explanation of a T-line. To be honest, most "T-lines" you see here, or any car audio site for that matter, aren't T-lines at all....

The speaker cabinet carpet (non-latex backed) like Partsexpress sells lets you hide the seams flawlessly. If regular automotive carpet is used, no matter who installs it, you will always see the seam because of the directionality of the carpet fibers, where as the speaker carpet has a random fiber that goes all over the place and can blend together. Super 77 is OK, but if you want carpet that will not come up, regular DAP Weldwood liquid is best (unless you have a gun that sprays the industrial stuff). I use alot of this, roughly a gallon for a 8-10 cubic foot box, you need to be liberal. And it won't soak through the speaker carpet even applied this liberal. I use a paint roller. Put at least 2 coats whereever there is MDF endgrain, as it will soak up the first coat. I have carpeted at least 100 boxes this way. I have seen some of mine from 15 years ago, to this day the carpet stays on strong and the seams don't show...

You can do alot with them, really... The last 8s project I did as with 8 RE8s. They did 143db on the termlab with 150watts total.... Most people don't do that with 1000 watts it seems... So I guess what I am trying to say is, you can get really loud with 8s if you build the box right... The getting low part has pretty much nothing to do with the size of the driver, it is much more dependant on the box and T/S parameters... Aditionally, 12 8s will give you a ton of thermal power handling... Much more than most pairs of 15s so you won't have to worry so much in that department... With a 3000d, all else being equal you'll have roughly 250 watts a woofer, should be plenty but not so much to get you in trouble....

Class Ds have similar efficiency, at least close enough to not matter (we are talking with 10% or so). Bottom line is, the more power the amp, the more power your electrical needs to supply, regaurdless of amplifier type or make. And what is to the max? Until they blow? Nobody can answer this for you without enclosure details.... A BTL could reach full output with far less power than you are talking in the right box. Additionally, there is no such thing as underpowering these (or any) subs. If you have 2 BTL 18s and only 4-500 watts each, they will still be louder than just about anything else.... If you have a few thousand watts each they will be louder, of couse, but this isn't mandatory. Additionally, once you get to a point where thermal and mechanical compression sets in (not much over 1000 watts) your returns on adding power exponentially decrease.... To the point of equalibrium at thermal failure....

Yes, it is from induction (inductance) and it becomes a problem when you take a 10" driver with a huge, long coil with tons of Le to get massive stroke and handle tons of power like Bob Carver did with his little sub. With XBl2, Underhung and other low Le, linear drivers, it isn't hardly an issue... Additionally, the subs like the BTLs are very efficient and don't need a lot of voltage to make bass... Drivers like a Solo-X and other purely over-hung motors with tons of X-max and huge, long heavy voicecoils have tons of Le and back EMF can become a considration... Back EMF also isn't an issue if you don't put your driver in a box so small and innefficient that it takes 2,700 watts to get it moving to full stroke....