[Gam3R]

Hey Guys,

I searched and turned up nothing, but hopefully someone has dealt with this problem.

Simply put, the rear 6x9 subs thump in time with wheel speed. The faster the wheels spin the faster the thumps occur.

FACTS:

-Engine speed does not affect it at all. Its just the wheel speed.

-None of the other speakers are affected by the problem, just the 2 6x9 subs.

-When the car is not moving the subs work just fine.

-With the volume turned all the way down, you can still hear the thumps, volume does not affect it.

-I currently have the sub's mini amp unplugged b/c the sound is annoying. This is not a new problem based on anything that I changed in the car. I bought the car with the subs unplugged.

Its not the mini amp b/c I just installed a new mini-amp/6x9 combo and both the new and original 6x9/mini-amp have the same problem.

It is a weird problem, I know.:hmm:

Can any guru's out there point me in the right direction for a fix?

Thanks in advance.

-B

 

[Gam3R]

wow i suppose this is rare. No one?

 

[Many330i]

Well, dude, you already have done the diagnosis - you just want us to tell you what you already know:

...the problem is either in your main amp on the driver side of the car in the trunk or in your Business CD player!

Doubtful but you may want to check the wire/wiring too 1. from the CD player to the main amp supplying the signal to the 6x9's or 2. from the main amp to the small sub's amp....and the subs themselves.

As a start: Get a friend with an e46, swap CD players and see if the thumping sound is still present. If present swap subs and check. The wiring in our cars is generally robust which will leave the main amp out as you said the subs amp is fine.

Also, while doing all this, make sure the ground wire is tightly secured. There is a chart somewhere here that will show you all the wires coming from the business CD and out of the main amp to speakers for reference.

G/L....and update!

 

[TiAg2247]

Do you mean they sound like they are bottoming out? Mine did the same thing when moving. I have no idea either, so I ended up disconnecting them and getting subs installed. Let me know if you find a solution, because I remember they sounded pretty damn good when parked.

Subscribed.

 

[Gam3R]

Hey, thanks for the interest. I decided to rip the amp out and take a look at it.
After removing the wiring harness I discovered the problem.
One of the pins on the amp was mashed down and snapped at the base. I'm not sure how someone could do that considering how much guidance you are given with the harness design. Either way, I snagged an amp for $90 and the problem is gone.

Fix one problem to reveal another! The rear deck is rattling from my rejuvenated HK system (I don't even have the bass turned up). I may have to throw some dynamat down to quiet it down...it never ends, right?

Alright gents that's the update! If someone has a suggestion for making the rattling stop other than dynamat, or some key spots to put it, I'm all ears! :thumbup:

-B