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pensacol
07-09-2007, 07:59 PM
I have a box designed by IonSQL. It houses 4 punch 8"s is 2.93 cubes tuned at 42 hz. For about 2 weeks I have been running 2 subs in it while the other 2 come back from Fosgate. It sounded awesome with 2. I added all 4 tonight and it sounds like udder crap. It sounds way distorted and kinda raspy. 2 of the subs excur more than the other 2. I also added about 12 oz of polyfill in the box. What's wrong? There are no leaks in the box. Do I need more polyfill, less polyfill, what could make it sound this way? Thanks for your help guys.

diminishedpower
07-09-2007, 08:01 PM
look to see if you wired it correctly, sounds like you wired the two new ones backwards

ThatChevyGuy
07-09-2007, 08:01 PM
subs wired backwards. Most definately. Use a drill battery, run the leads to the + and - on it, if they **** in, wired backwards. do it to each sub.

blackbonnie
07-09-2007, 08:12 PM
x3, check your wiring

tru_44
07-09-2007, 08:17 PM
does box have dividers?

pensacol
07-09-2007, 08:53 PM
The attached image is how it is wired. I did the 9 volt test and they all were the same. And no they aren't divided. Just one big box.

diminishedpower
07-09-2007, 08:57 PM
i would still pull them all way out and triple check cause it sounds like 2 of them are 180 degrees out of phase (cause 2 to hit outward as 2 are hitting inward causing what your describing)

tru_44
07-09-2007, 09:04 PM
maybe having 4 subs and no divider is the problem or are u running the subs reverse

pensacol
07-09-2007, 09:15 PM
Ok wiring is confirmed. I have triple checked the wiring and it is all right. I sure hope I don't need to build another box for these. But if the box is built and ported to the specs of the subs having dividers should not be a problem right? I could be wrong though.:)

mlstrass
07-10-2007, 02:35 AM
Have you tried the 2 "new" subs alone? Maybe they're messed up and causing the crappy sound. Try those 2 alone in the box and see what happens.

If the box was designed for 4 subs then it shouldn't be the box, wiring checks out, so maybe it's the subs.

mlstrass
07-10-2007, 02:37 AM
Also wonder if 2 subs are different ohms. Verify with a DMM, just to be sure all are ohming ok...

pensacol
07-10-2007, 07:12 PM
I had 2 of them running off of a JL 250/1 so they were getting 125 watts a piece. Now that I have 4 on the same amp they are getting 62.5 a piece. I am turning it up to the same volume. Could it be underpowering the subs and causing them to sound like that. The subs are rated for 150 each. Could getting the right size amp make it sound better?

shortyg83
07-10-2007, 07:18 PM
yea that does sound underpowered but also how did you run only 2 before? if it is one box did you just leave the other 2 subwoofer spots open

diminishedpower
07-10-2007, 07:21 PM
UNDERPOWERING CANT HURT ANYTHING!!!

Anyways if its messing up with that low power it will with bigger amount, but yes check ohm of every speaker with dmm

shortyg83
07-10-2007, 07:25 PM
UNDERPOWERING CANT HURT ANYTHING!!!

Anyways if its messing up with that low power it will with bigger amount, but yes check ohm of every speaker with dmm

well half true
underpowering cant hurt things with gains set correctly.
but it can make it sound like crap. just because it sound like crap on a lower power doesn't mean it will on a higher one.
How big is that box your running them in also? the cutting in half of box size is probably the biggest problem.

pensacol
07-10-2007, 07:26 PM
When I only ran 2 I did not cut out the holes for the other 2 yet. It was still solid board. I have also checked the new ones and they are 4 ohms also. With all of them wired like the about picture I get 4 ohms from the amp when on. This has me stumped. I figured 2 more would make it sound better, but I had no idea it would make it sound like crap. The low bass like 35 to 40 hz sounds good, but a little higher and it's just awfull(?) It sounded good throughout with only 2. I guess the old saying the more the better doesn't apply here. Fosgate recommends like .65 cubes per sub, and 2 sounded really good in a 3 cube box.

diminishedpower
07-10-2007, 07:32 PM
well he specifically said two were acting different, that wouldnt be power issue unless its related to ohm load

Second no sub should sound any worse with lower power unless there someone who tries to overcompensate with gain which just clips and then its the clipped signal not the low power.

diminishedpower
07-10-2007, 07:34 PM
anyway running the two in that huge box maybe over drove them and loosened the suspension so now with all four(2 with stiffer suspension that other 2) their acting irregular?

pensacol
07-10-2007, 07:45 PM
It could be. I have had to glue the spider back on one of the older ones already. Also I have set the gain to the voltage specified in the JL manual for 4 ohms so I don't thank that's it. The older ones are only about 1 month old. I ran them in this box for about a week. If you push in on the cone they are tight, like they were when I got them. What about a break in period. Do you think that might be part (or whole) of the cause? The older ones have been broken in, where as the new ones haven't yet? I am going to do one of the other suggestions and unplug the 2 older ones and see if the new ones sound like it did before. There might be something wrong with them.

shortyg83
07-10-2007, 07:52 PM
Set the gain using a dmm. try just 2 of the new subs by themselves if you can

diminishedpower
07-10-2007, 08:05 PM
from sounds of it you did stretch the older ones out more, unless i couldnt understand what you were saying. When lightly pushing on the subs does the suspension feel like its the same strength, preferably do this outside a box

pensacol
07-10-2007, 08:13 PM
I am going to unplug the 2 older ones and check how the new ones sound. I will also test the suspension when they are out of the box. I will let you know the results. Thanks for all of your help and time.

pensacol
07-10-2007, 08:56 PM
I got it!!! I pulled them out, checked the cones, they all felt the same. Played the new ones, sounded great. I said what the heck and pulled all of the polyfill out of the box, put everything back in, and it sounds awesome! I always thought polyfill would help some, but didn't think it would make it sound that bad. Now I just need to upgrade my amp to be able to get full power out of them. Thanks very much for your help guys (gals if there are any). I really it.

mlstrass
07-10-2007, 10:26 PM
cool, glad you got it figured out...

tru_44
07-10-2007, 10:35 PM
cool, glad you got it figured out...

x2