Need help selecting a subwoofer. Infinite baffle questions.
 

I replaced the head unit in my '98 LS400 (pioneer original) and as expected I'm somewhat disappointed with the factory sub. I don't quite know why but the sub sounded a lot better with the factory equipment and no matter how I tune it I'm just not happy. It recreates strong sub 50hz signals surprisingly well, but generally anything above that sounds muddy and it also sounds like the speaker is maxing out it's travel. I have my LPF set to 50hz with a 12db slope so it sounds somewhat decent, but I know I'm missing a lot of upper bass frequencies and it's quite apparent in a lot of songs. Okay so I'm asking too much out of a 13 year old paper sub.

I want to install a replacement driver in the stock location. I don't want a sub box. The problem is my limited understanding of selecting the right driver for an IB setup, and I want to do this the right way. Through some research I'm hearing things about cabin gain, and QTS (I know a bit about TS parameters but not enough). Obviously going with another 8" would be the easiest, but I'll do the work to sub-mount a 10" to the rear deck if it's really worth the trouble. I think an 8" might be okay, and that simply having a better quality speaker would make all the difference in the world. I'm running an Audiopipe APSM-1150 rated at 150watts @4ohms. Not the most powerful amp in the world but from what I understand I wont actually need much power.

Here's some that I'm looking at:
http://www.crutchfield.com/p_114D308...D4.html?tp=111

http://www.crutchfield.com/p_20610C8...nvpair=FFSize|[rank6]8%22&tab=features_and_specs

On this one the shallow mount idea is nice but the QTS is absurdly high at 1.64

http://www.crutchfield.com/s_130SW84...nvpair=FFSize|[rank6]8%22

Any suggestions?

check out the pioneer shallow mount sub.. i dont rec using it freeair but.. u can build a tiny enclosure (literally just big enough to hold the speaker) and u'll be impressed w/the output..

http://www.pioneerelectronics.com/PU...TS-SW2501S2|S4

if ur set on an 8" go w/the diamond audio.. incredible company, great product.. i've used diamond audio in my last 3 cars..never a problem.. amazing sound quality

that said in my Ls im lookin to save trunk room so i am lookin an the shallow pioneer 10's.. done a few cars recently an i'm VERY impressed..

So I plugged the parameters for 4 different subs into WINISD, using a sealed enclosure volume of 421 liters (the LS400's trunk volume according to the specs) and found that they show to be remarkably similar in response if the graph is to be believed, with the exception of the shallow mount Pioneer 8" which has a big peak at 80hz. The Pioneer does seem to be the strongest at a little below 50hz but I'm concerned that the 80hz peak will make it sound boomy. The next strongest one is the JBL (the pink line), but that's mostly in the subharmonics which doesn't really matter. Is this graph believable? If it is true that they're all pretty much the same which one would I choose? The JBL and Kicker are really cheap (about $40) whereas the Diamond audio and Pioneer are like $140.

The 4 subs are:

Pink- JBL GTO804D
Orange- Diamond Audio D308D4
Blue- Kicker Comp8
Yellow- Pioneer TS-SW841D

Attachment 219933

my cousin uses that same program by pro box, lol. really good stuff there. where are you located OP ?

I'm in NYC.

Have you checked the max excursion in WinISD?

Yeah I inputted Xmax into the parameters for each of the subs. Actually I realized that I was using the "gain" graph instead of the "SPL" graph. Here's the SPL graph.
Orange- Alpine SWR-823D
Yellow- Pioneer TS-SW841D
Blue- Diamond Audio D308D4
Green- Kicker Comp8
Red- JBL GTO804D


Attachment 219978

If the graph is to be believed, the JBL is quite efficient and should be the obvious choice (to a newb like me). I'm curious though as to how the Pioneer will sound in the real world and I'm having trouble imagining it.

What is your power level and the excursion graph?

With IB subs, you nearly always run out of excursion before reaching the RMS power rating on a sub.

Where's the excursion graph function in winisd? My amp is rated at 150 rms at 4 oms.

Are you using WinISD or WinISD Pro? It's been years since I used them. I've used Unibox exclusively since Dan Wiggins said it models very close to LEAP.

The free one. I may give Unibox a try. And I think it would also be a good idea to see what exactly it is I don't like about the factory sub. Meaning I'm going to go in there with a signal generator and a sound level meter (which I own) and map out the response curve.

Room EQ Wizard (aka REW) is the best free software. There is also a free spreadsheet that works with the Radio Shack analog SPL meter. (REW works with it as well as a few calibrated mics).

If you have some meter that isn't listed with this software then it is not accurate. As popular as the RS meter has been over the last decade with the home theater crowd, it is wildly inaccurate. That's why there are correction value files in REW and that spreadsheet. Without the correction, the meter is off sometimes as much as 12db at different frequencies.

Actually the one I have is indeed the classic Radio Shack analog SPL meter. I've owned it for more years than I can remember. Do you plug it into the computer's mic input? I wonder how horrible my laptop's built in mic would be for this purpose?

Edit: Never mind. Reading the documentation now. It says laptop mics suck. Cool app BTW. Cant wait to use it.

if you're going to run free air in the trunk, make sure to seal up all the holes in the rear deck and replace the factory (old) trunk seal hinge. will be $80-100 well spent.