Hello everyone I am new to this site. I have a 98 ML 320 and it came stock with a very poor sounding tape deck and speakers (not bose). I had a significant sound system upgrade put in however it does not sound like I thought It should. I was wondering if anyone else has installed a similar system or has any tips to make mine sound better. This is what I had done:

Kenwood Excelon Head unit MP3 5V Preouts 3 sets
Rockford 1500W 4 CH
MTX 1000W Sub Amp
Infinity Perfect 6.5 Components
Infinity kappa 5.25’s
Kenwood HQ 1000W Sub
Dynamat Extreme: Doors, Hatch, Roof

It sound quality is crystal clear but the perfects don’t seem to have very much mid bass. It actually sounds better/fuller in the back seat with the cheaper 5.25’s!

The cross-over in the amps is set to all pass.
The cross-over in the deck for zone 1 (front speakers) is set to 70 Hz
The cross-over in the deck for zone 2 (back speakers) is set to 70 Hz (sounds fantastic in the back seat!)

I have tried adjusting the gains and every setting in the deck! Is it the positioning of the speaker wells in front doors on the ML? Do I have defective speakers? Anyone have this experience?

Thanks in advance.

Hi.

1) Only for the 4 channel amp I hope.

2) Easy to check. Swap the rear output
wires at the amp with the front ones, if the
front speakers now sound good then they are OK.
If they sound the same then they are defective.
If the problem moves to the back then the
speaker outputs are the problem.

It sounds as if the output wires for the front are wired out
of faze.
Meaning one front speaker is getting + to + and
- to - to the terminals and the other is getting
+ to - and - to + to the terminals.
You'll have to remove the front speakers to check though.

They will cancel each other out and the result is
poor performance.

But then again if you had this installed, and if you used
a reputable stereo shop they should stand behind their work
and should make no problem of troubleshooting this problem.
And it should be free.

If you used best buy, pep boys or the like then this sort
of mistake doesn't surprise me but this doesn't take away
from the fact that they should rectify their mistake.

Louis.

Hey Thanks! I did get it done at Future Shop (best buy bought them here in Canada). I think it may be “out of phase” now that you have described it that seems most likely. I will take it in and see what they can do. There should be no way that Kappa 5.25’s sound better than 6.1 perfects!

My tought exacly.

Louis.

Well had a little spare time this weekend so I did a little disassembly. Used my trusty multi-meter and found that the left side was backward. I swapped the + with the - and it sounds way better. Thanks for the advice it was right on!

Louis.