[bmw325i]

I don't remember the exact cost but I went all out on my 15" Fi BTL and I know it was under $200. I got an extended voicecoil(longer than fi's external coil) and triple external leads(fi had dual internal leads that burnt out on me). I reconed it myself just got the kit from them. I had that sub in a larger than reccomended box(7 cubes net tuned at 28hz) powered by my Audioque 2200d subsonic filter at 20hz. When I burnt out the tinsel leads it was powered by a pdx m12. That's why I hate internal tinsel leads on a high powered sub I never had an issue after that.

Contact them for a quote and see what they say. Tell them what your setup is and they will tell you what will work best.

Whatever you do don't get a kicker

[kaigoss69]

Originally Posted by joeyc123

Yeah Kai, I agree with you. Your AE sub was wonderful. But I need to be honest with myself, I'm a basshead at heart and 500 or so watts can satisfy my needs completely with an IB setup, and that poor AE sub was taking a beating trying to keep up with my needs. What kind of parameters constitute a good subwoofer for what we do in our trunks with IB?

For instance - just as a random example - the 15'' kicker L7 solo baric. For IB in our trunks, good? bad? why?

Most subs that work in medium to large sealed enclosures will generally work in IB. There used to be a belief that a sub had to have a Qtc of around 0.7 to work well, but everything I have read in the last few years, and based on my personal experience, is that everything between 0.4 and 0.7 will work, and most people actually prefer the sound of the lower Qtc subs. The other spec that used to be the litmus test of whether a sub would work or not is VAS. The rule used to be that the enclosure (trunk volume) had to be at least 10x VAS, but that is no longer true. Today, subs are built better and are more versatile.

In a single sub application, the most important spec is cone displacement. The more air the cone can displace, the louder the sub can play. The diameter of the cone determines the surface area, which is pretty much the same for most 15" subs, so the true difference maker becomes the excursion capability (xmax) of the sub. Look for xmax values higher than 15mm, and the higher the better, as long as it is not an SPL type sub, which will not sound very good. The key is to get an "SQ" type sub that'll give you the output you want (the L7 is not an "SQ" sub, and I believe it was designed for ported enclosures). Keep in mind, when a sub comes close to its xmax it produces lots of distortion, so having a driver with high xmax capability is almost automatically a recipe for high volume and low distortion.

Luckily, there are many subs out there that have proven to work well in IB, in all different price categories. Just based on what I have read on another forum, the JBL GTO15 and ID15 work very well in IB and are great alternatives for the budget-minded. Unfortunately the JBL is very hard to find since it is discontinued, and the ID only has 13 mm of xmax, which may mean you need two of them to get the volume you want. I do believe though that there is more than xmax that determines the "loudness" of a subwoofer. With my current sub, it gets very loud with less than what seems 10 mm or so of xmax, a mere 1/3 of what it is capable of. Also, when I had my Infinity 12 hooked up, it got pretty loud with only about 15mm xmax (remember its a 12). In comparison, the AE never got quite loud enough for me, even at what seemed to be close to full xmax (the point when I started hearing distortion). This may have to do a little with the "stealthiness" of the AE, which may not be desireable if you are a bass head. If you want to stay in the budget category, I'd say find a GTO15 and you'll probably be very happy with it. Another alternative would be to buy a more expensive sub used.

There is plenty of reading material on the subject at d i y m a . c o m and I encourage you to check it out before you make a decision. As far as I am concerned, my IDMAX15 is the bee's knees in this category, and it would be my recommendation if your budget allows it.



Since you only have room for one sub, my advice would be to get the best sub you can afford.

[kaigoss69]

Looky looky!

http://www.sonicelectronix.com/item_...-COMPLETE.html

[bmw325i]

I still think a 15" fi q fully loaded with high qts would work great in "infinite baffle". Mainly because it has 28mm of Xmax and the power handling. I've read that fi could modify the sub with a different suspension for those using it in this application as well. Just something to keep in mind.

[kaigoss69]

Originally Posted by bmw325i

I still think a 15" fi q fully loaded with high qts would work great in "infinite baffle". Mainly because it has 28mm of Xmax and the power handling. I've read that fi could modify the sub with a different suspension for those using it in this application as well. Just something to keep in mind.

Specs look good!

[joeyc123]

I may try to test out that JBL GTO, its pretty cheap and Ive been reading reviews on it lately. May as well right?

I've got my old jl audio xd 700/5 amp running while I wait for the pdx-v9 to get repaired.

Quick question that one of you may understand: For some reason when trying to put the channels 3/4 in bandpass mode no sound can be heard from the woofers. Only in highpass mode will the woofers play. Any ideas?

[kaigoss69]

Originally Posted by joeyc123

I may try to test out that JBL GTO, its pretty cheap and Ive been reading reviews on it lately. May as well right?

I've got my old jl audio xd 700/5 amp running while I wait for the pdx-v9 to get repaired.

Quick question that one of you may understand: For some reason when trying to put the channels 3/4 in bandpass mode no sound can be heard from the woofers. Only in highpass mode will the woofers play. Any ideas?

Yep, also keep in mind that the baffle that you do have will only support a fairly light subwoofer, and anything significantly heavier and more powerful will require a much more rigid and larger baffle.

[bmw325i]

That sub seems a little low on power handling don't you think? With only 15mm of xmax and rated at 350rms (in a box) I would expect it to handle 1-200 watts "infinite baffle". I understand it's a cheap price but when I blow a sub I replace it with a better one.

[kaigoss69]

Originally Posted by bmw325i

That sub seems a little low on power handling don't you think? With only 15mm of xmax and rated at 350rms (in a box) I would think you could only put 1-200 watts to it for "infinite baffle". I understand it's a cheap price but when I blow a sub I replace it with a better one.

A lot of people equate power handling with SPL, which is wrong. Others think that if you have more power than what the sub can handle, you will automatically blow it. That is also incorrect. Let's not forget that volume (SPL) comes from cone displacement. If this sub reaches 15mm xmax at 200W, and another sub requires 500W to reach 15mm xmax, does it make one louder than the other? No! It just means that one is more efficient than the other. Amplifier output can be adjusted/limited (JL Audio method) in case one has more amp power than the sub is rated for, but I personally never had the need to do so because it does not require a trained ear to recognize the onset of distortion, which almost always is the first warning sign before reaching the mechanical & thermal "danger" zone. But of course accidents can happen, so for anyone who is not 100% comfortable they can always reduce the output of the amp with the JL Audio gain setting method.

[bmw325i]

Originally Posted by kaigoss69

A lot of people equate power handling with SPL, which is wrong. Others think that if you have more power than what the sub can handle, you will automatically blow it. That is also incorrect. Let's not forget that volume (SPL) comes from cone displacement. If this sub reaches 15mm xmax at 200W, and another sub requires 500W to reach 15mm xmax, does it make one louder than the other? No! It just means that one is more efficient than the other. Amplifier output can be adjusted/limited (JL Audio method) in case one has more amp power than the sub is rated for, but I personally never had the need to do so because it does not require a trained ear to recognize the onset of distortion, which almost always is the first warning sign before reaching the mechanical & thermal "danger" zone. But of course accidents can happen, so for anyone who is not 100% comfortable they can always reduce the output of the amp with the JL Audio gain setting method.

Sure you could adjust the amp so the sub only gets 200 watts using a multimeter but I just think that it would be easy to go over that setting. And personally I would look for a sub with as much xmax as possible for this application.

[kaigoss69]

Originally Posted by bmw325i

Sure you could adjust the amp so the sub only gets 200 watts using a multimeter but I just think that it would be easy to go over that setting. And personally I would look for a sub with as much xmax as possible for this application.

If money was no object, sure. But a sub that is known to work great IB with 15 mm of xmax for $99 can't be beat.

[joeyc123]

I agree with both of you.

Right now, at this point I have a large curiosity pertaining to how different woofers would sound, and given the reviews for the GTO at the price that I bought it at, I was able to convince myself that it was worth it.

But BMW is right as well, given that I said I was a bass head, i'll likely end up purchasing an IDmax or Fi sub later on down the road, but for now - i'm excited about trying new things.

[bmw325i]

Originally Posted by joeyc123

I agree with both of you.

Right now, at this point I have a large curiosity pertaining to how different woofers would sound, and given the reviews for the GTO at the price that I bought it at, I was able to convince myself that it was worth it.

But BMW is right as well, given that I said I was a bass head, i'll likely end up purchasing an IDmax or Fi sub later on down the road, but for now - i'm excited about trying new things.

If you decide to try out the Fi sub down the road send them an email and let them know you'll be using it in a "infinite baffle" setup. They can customize it for this application. I wouldn't reccomend the internal leads I think it puts too much stress on the leads because of the amount of xmax these subwoofers have.