Habious

Hey folks,

I'm wondering if anyone else is having/has had this issue before.

My rear speakers sound "weird". I consider myself a bit of an audiophile nut and I'm pretty picky about my music, especially in the car.

When the top is down, everything's fine, system sounds great. When the top is up, the rear speakers sound out of phase. If I run the fader all the way to the rear, the sound is muffled and "swooshy" (not sure how else to describe it). With the fader all the way to the rear, if I run the balance all the way to one side, I still have sound coming from both speakers but, more one side than the other and not nearly as "out of phase" sounding. This happens with any audio source (FM, tape, CD, Sirius through VaisTech interface), every CD I've ever run through the system (had the car about 9 months). I even took the VaisTech interface and harness out of the system, just to make sure that wasn't causing problems; didn't make a difference.

I've taken it to the dealer (it's still under warranty). They told me they couldn't find anything wrong with it. I went out there (45 min. drive for me and the Mrs.), grabbed a tech, and showed him what I was experiencing. He seemed to agree that it didn't sound "right". I even went so far as to sit in another SC430 in the dealer lot and listen to that stereo. It sounds good; there is discreet left and right audio in the rear speakers.....mine just sounds wrong. But, when they came back the second time, they're still telling me "no trouble found".

I can't even listen to the stereo with the balance and fader set to "0" because the out of phase audio mixes with the in-phase audio from the front speakers and it's just really weird to listen to. I have to set the fader to F2 at least so I can't really hear the rear speakers.

I know that the fronts are 3-way and the rears are a single, full-range speaker so, they're not going to sound the same. This isn't a dynamic range issue. Also, with the top down, it's fine; left is left and right is right and it's all in-phase.

The car is with the dealer now and I'm going to go out there tomorrow and 'splain to them...again...what it's doing and hopefully get them to actually admit that there's a problem. They've had the car for 5 days now (long story).

Anyone else ever experienced this or heard about it? And, more importantly, have any idea what it might be?

My first guess is something in the head-unit or possibly crossed wires in a harness somewhere. The audio clearly changes from good to bad when the top is down/up.

Thanks,

Greg

EJC

" When the top is down, everything's fine, system sounds great. When the top is up, the rear speakers sound out of phase. If I run the fader all the way to the rear, the sound is muffled and "swooshy" (not sure how else to describe it). With the fader all the way to the rear, if I run the balance all the way to one side, I still have sound coming from both speakers but, more one side than the other and not nearly as "out of phase" sounding. "

My first inclination based on the description of the sound is that the rear channel of the amp was gone.

This doesn't make much sense if things are OK with the top down,
I am assuming when you say that things are OK with the top down that you were standing still and were able to hear the speakers clearly .

This leads me to believe that when you close the top the mechanism is shorting you amplifier. A VOM across the speaker leads might show this difference between the top up/down. You can check for both the signal voltage and a short. They could also try connecting speakers directly to the amp output., a good signal will confirm you have a wiring harness problem not a speaker/amp problem[/COLOR]

dseag2

From my experience, most speakers provide very little sound when you adjust the fader all the way to the rear. This is due to the "crossover" in the system. My GS300's were the same way.

TexTopDwn

I am having a simular issue to this post. But mine does not change with the top up or down. The front speakers sound fine, but with the fader at 0 you can hardly hear anything coming from the rear. And when the fader is moved to the rear it is not very loud and muffled sounding. Also changing the Balance Left to Right does nothing sound comes from both sides either way you turn it. When the Fader is turned to the Front the Front all sounds great and strong and the Balance works correctly. From reading other posts I assume I have a problem with my amp?? If this is true is there a way to just replace the amp with a different one since I also read that the ML stuff is crap. My front speakers were already replaced when I purchased the car a few months ago. So I want to just play them till they blow before I do a full change out. Is there an amp that I can just purchase and plug in (maybe with an additional harness) that will work with the stock system?
Thanks for any help or suggestions!

mrblister

AS far as memory serves me . i would not gurantee this.

I remember years ago when stereo first came out there was a polarity to the speakers. As I remember the idea was to have both speakers moving in at the same time or out at the same time. So if you had reversed the wires on one speaker that would cause that speaker to behave opposite to the other speaker. I remember the test was to use a battery 1.5 volt and if you put one of the speaker wires to the positive of the 1.5 volt battery and the other wire just tapped the neg side of the battery you could tell which way the coil was moving. It was important to have them in phase . the other way you could tell was to listen to a demo of a train moving and you should hear it move fron right to left and it should sound in phase.

Pnuge88

iTrader: (1)

If my top is up and closed the rear speakers are low when you turnthe fader all the way to r7, the rear. When the top is down and open.. The rear speakers play louder. I figured its normal considering all the wind noise and open cabin the speaker would adjust itself to play louder whenever the top is down.

Darthspeed

I also believe you have a problem with the amp. When the top goes down and you hear the " ding" telling you the top has completed the full cycle. The amp changes DSP settings. The system uses DSP to create a center stage digitally when the top is up and doesn't when the top is down. This is done digitally in the amp. Also, the inputs to this amp are balanced. Like XLR on most high end amps. This leads to less noise, and ground loops. That causes problems replacing with a regular amp because the RCA are unbalanced. Secondly, our speakers are 8 ohm and would suck alot of te power from your amp, roughly Hal the rated power at 4 ohms.
Anyways, it's in your amp.....

finallyayo

Someone posted this on the SC430 Mods Facebook Group:

DshngDaryl

That is probably one of the reasons the "Mark Levinson" system was touted so highly when it first came out.

Of course, you can't believe everything you read on the internet.