1997 bmw 528i bass cuts out when lights dim

[120alexis]

I got a 1997 bmw 528i i put ab aftermarket sound system and everytime the bass hits the bass cuts out i have tried different amps and subwoofers but nothing has fixed it. The lights also dim it only dose it when the car is on if it is off it dosent do it at all. Can it be not enough power from alternator? Its a 140amp bosh alternator.

[edjack]

What is the battery voltage when the bass cuts out? Have you verified that the battery cables are clean and tight?

How old is the battery?

[120alexis]

It drops to 13.34 and goes up to 14.34 and sometimes drops to 12.30

- - - Updated - - -

It drops to 13.34 and goes up to 14.34 and sometimes drops to 12.30. Battery is from 07/14

[JimLev]

What gauge wires are you using from the battery to the amp?
You do have the amp connected directly to the battery, right?

[120alexis]

Yes i got 4guage

[777300ER]

You need caps inline.

[120alexis]

What is that?

[HoZy]

Don't listen to him, You don't need a damn capacitor.

Amp is grounded directly to the battery as well? If not check your ground.

Age of battery? Car has no issues starting?

What sub/model & what amp?

Post some photos up of your wiring/install.

Cheers
Mat

[120alexis]

It is grounded to chassis and does not have starting issus. I dont know how old the battery is but it dose have white corrotion on it the battery has the date of 07/14 it is a evermaxx. The amp is a precision power 3000watt the subs are bass inferno 1500 watts each. I have tried changing amps and subs and dose the same thing.

[HoZy]

It is grounded to chassis and does not have starting issus. I dont know how old the battery is but it dose have white corrotion on it the battery has the date of 07/14 it is a evermaxx. The amp is a precision power 3000watt the subs are bass inferno 1500 watts each. I have tried changing amps and subs and dose the same thing.

Check, double check & triple check your ground.

Deal with this all the time.

Cheers
Mat

[120alexis]

I had it to the battery but i switched it to the hole were the battery braket bolts to i sanded it to bare metal.

[HoZy]

Are the amplifiers going into protect mode or what?

As I mentioned earlier, please post photos of your install & wiring.

Cheers
Mat

[120alexis]

No the amps do not go into protect mode the bass just fades out.

[HoZy]

Also your amp & sub are not 3000w & 1500w

Your Amplifier Precision Power "3000w" is

• 4 ohms: 495 watts x 1 chan.
• 2 ohms: 1000 watts x 1 chan.
• 1 ohm: 1475 watts x 1 chan.

And your walmart "bass inferno" subwoofers are not "1500w" they are 500wrms dvc 4ohm units, if you're lucky.

So how are the subwoofers wired? Post photos.

You'll either have them wired for 1ohm or 4ohm,

So please, I'll mention a third time. How is everything wired?

What headunit? RCA? Using a LPF on factory unit?

Explain more & post pics mate.

Cheers
Mat

[120alexis]

It only does it when the engine is runing

[120alexis]

The subs are wired to 4ohms the headunit is a soundstream flip up i got the monoblock plugged into a epicenter for the component amp i have it wired using the oem speaker wire i got 2 kicker speaker in front doors and soundstream tweeters the subs are svc i had it wired to 2ohms but dropped it back to 4ohms to see if that would help but it didnt.

- - - Updated - - -

Im gonna have the battery tested tomorrow to see if it is still good. I also got a equalizer .

[HoZy]

So you're feeding your subs 247wrms each only, Okay. (Not your issue, but also stupid considering you have an epicenter.)

To me this sounds like a "my cousins, brothers, girlfriends, sister knows a guy who's uncle can install this for me for a case of bud light".

Cheers
Mat

[120alexis]

I have found the problem. It was the eq i took it off and all the problems went away.