OK I have a problem.

I have installed 2 x Sony Xplod 12 inch subs to my car. I am not 100% sure about where they would be best situated in the boot (sedan), at the moment they're at the back of the seat facing forward which seemed to me like the best option.

However I have some major sound issues. In my last car (mazda hatch) one of these subs would give you chest pains, now with the same amp, same sub plus an extra sub and amp to run it I wouldnt consider it impressive enough to show off to a randy teenager.

What irritates me the most is my old deep bass sound has been replaced to what sounds like death to smoochee, the sound seems distorted even though it isnt.

Any ideas?

By the way, the head unit is a Sony MEXR1 dvd head unit thingo, im not 100% sure if its something here killing my performance but im doubting it. Anyone with same headunit but and similar problems please feel free to post your ideas.

put a subwoofa in the back mate!

my guess is that you have them facing into the cabbin? i think that most people have them facing towards the boot(i know that i have). i think that they are distorting because they have to come thru the back seats and from memory a nice peace of metal as well... just my thoughts

This may sound obvious but have you tried opening up the centre armrest?
You can try facing them to the boot and see if that makes a difference. The distortion sound could well be something rattling though, try grabbing your rear view mirror firmly next time you hear the distortion sound and see if that makes a difference.

The distortion sound could well be something rattling though, try grabbing your rear view mirror firmly next time you hear the distortion sound and see if that makes a difference.

lol, mine is doing that. off topic, is there a way of tighting the mirror in a TJ. i know that you can in a TR, but i NFI if i can do it in the TJ.

best thing to do is to have your subs facing towards to boot not the cabin, how many watts RMS are your subs and amp? i have the feeling that your amp doesnt have enough power to run the two subs and might involve alittle distortion, how old are the sub and how have you got them wired up? are the 4ohm or 2ohm?

lol, mine is doing that. off topic, is there a way of tighting the mirror in a TJ. i know that you can in a TR, but i NFI if i can do it in the TJ.
blutac is your friend ;).

best thing to do is to have your subs facing towards to boot not the cabin, how many watts RMS are your subs and amp? i have the feeling that your amp doesnt have enough power to run the two subs and might involve alittle distortion, how old are the sub and how have you got them wired up? are the 4ohm or 2ohm?
Ahh didn't even tweak to me that he'd added a sub but kept the same amp. I'd say that's what it is. Should be "Feeling" more bass, but won't be as loud.

i added another 12" to my system and all it did was make the car shake more :) and also the car rattles alttle more thanks to them loose bits everywhere. i dont get any distortion when i turn my system up to about half way cause then i start to loose alittle power from the subs, well thats until i get a second amp installed :D.

Couple of things:

A magna is heaps bigger than a little mazda. Larger amount of air to vibrate.

Sedans do not bass load as well as Hatches.

Sony subs are crap (blown heaps of them with good clean power too).


Suggestions:

Rear-load the subs by firing them BACKWARD with the sub box as far backwards in the boot as possible, ie right up against the bootlid

Open Ski-port.

You can face them towards the front, but you need to seal the box to the ski port. Blankets work great for me and my 2x12" prefabbed sub box.

Hey guys, thanks for the input.

I know the deal with the dead sony subs. I killed a few 10's back in my lancer, most didnt last a week out but oh well, they were cheap.

These things are pretty good value for me and 1 i've had for 4 years, the other is just new (but same) and still going strong.

I've fired backwards and got a good rise. Now all i need to do is tune the headunit a little and we'll all be good.

Thanks guys, you're my heroes.

$50 says the subs are out of phase.

did you change the headunit when you changed the cars?

i previously had a decent JVC headunit, which had 4V pre-outs

then i upgraded to the Eclipse DVD unit, the pre-outs are actually less than 2V, and has effected sound rediculously. only just got it back to the pounding it used to have, after upgrading amps and sub plus a lot of tuning!

Last HU was a crappy Sansui thing which had 2v preouts. This thing has 4v ones afaik.

All sounds ok now. It's taking a little getting used to the whole boot space as opposed to open design of a hatch. More doof doof with a hatch but still sufficient now to keep me happy.

Another note I should make, is with the PS2 running straight into the HU I get a hell of a lot more bass via it than from a dvd/cd etc. Weird huh? :)

$50 says the subs are out of phase.

Thats a big possibility, sound waves cancelling each other out. You know, peaks and troughs....anyways, yer check if they're in phase. Also facing a sub towards the boot gives 4 extra dB in bass notes because it comes off the chassis of the car, 10dB means 10X as loud so I geuss 4dB is in the vecinity of 2 - 3 times as loud.

Thats a big possibility, sound waves cancelling each other out. You know, peaks and troughs....anyways, yer check if they're in phase. Also facing a sub towards the boot gives 4 extra dB in bass notes because it comes off the chassis of the car, 10dB means 10X as loud so I geuss 4dB is in the vecinity of 2 - 3 times as loud.
haha doesn't quite work that way.
With every 3dB increase, the volume will double. So 4dB extra will be just over double the volume (however you can't just say, 4dB increase, will be soooo many variables). 10dB increase would be around 4x louder, just over.

As has been said... Phase... Try fliping neg and pos on one sub (at the sub or at the amp) to bring it in phase with the other sub. Means you've messed up wiring somewhere.

This sounds like all the symptoms anyway.

Tis all good guys, fixed, works great.