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#3441 - 23/11/1999 23:16 Digitized Noise, Alternator Whine, Speaker Pop
Elite M3
member

Registered: 15/09/1999
Posts: 101
Loc: Sunnyvale, CA, USA
I have had the EMPEG installed for about a month now, and still have no way to get rid of Alternator whine, Speaker pop (on Power ON/OFF), and the digitized noise at all times when car is on or off. I have a BMW 99 M3 and I bought a brand new A/D/S/ P840.2 amp for the occasion. The digitized noise is the most annoying of it all because on slow songs that don't have a lot of treble it is horrible. The digitized noise does not change with volume or RPM, it is constant. The alternator stays the same volume but frequency changes with RPM. And the loud spike is there when I power it off and on, but mostly off. I have tried the grounding RCA's as directed, and that just seems to make the digitized noise worst and the sound somewhat muffled. I have pulled the EMPEG out and taped up everything that is/isn't being used and the back of the harness as well. I have the unit mounted in the glove box and the engine noise is there if I am holding the unit in my hand in the car with the glove box out as well. I have also tried isolators (from pyramid) and that made the sound terrible. I am completely out of options. I had the unit professionally installed and from what I can tell, they wired the power to some accessory power and used the in-line power filter (at first they didn't and I had speaker pops when I hit the brakes, turn-on anything...). The ground is however going straight back to the GND of the AMP in the trunk, as is the Remote AMP on wire. I am only using the rear outputs of the EMPEG and taped up everything metal (includeing the gold RCA connectors). I have the factory deck going to the input of the EMPEG and I switched the jumpers on the board over from 1V input to 4V input. Does anyone have any suggestions or see anything that I have left out?

-Jason Sarich
Sunnyvale, CA #00018


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#3442 - 24/11/1999 04:28 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
schofiel
carpal tunnel

Registered: 25/06/1999
Posts: 2992
Loc: Wareham, Dorset, UK
You could try measuring the DC earth voltage at both the empeg and the amplifier with an accurate voltmeter, relative to the battery - terminal. This should be done with the engine on and the system playing. If you have more than a few mV voltage difference, you may have a bad ground somewhere. What swg wire was used for the power & earth wiring? Did you look at grounding the bonnet across one of the hinges with a flexible braided strap? What sort of ignition leads do you have? You could try changing to resistively-suppressed ignition leads.

I have to confess I have had real trouble getting rid of noise in both BMW and VW before now, even with just an ordinary radio and a complete, dealer-supplied suppression kit.

_________________________
One of the few remaining Mk1 owners... #00015

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#3443 - 24/11/1999 08:38 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: schofiel]
dionysus
veteran

Registered: 16/06/1999
Posts: 1222
Loc: San Francisco, CA
...on that note, let me ask something that I'm unclear on:

The piggy-back ground wire - where is the original ground supposed to come from? In the back where the amps are at, or from the front where the empeg is at?
-mark


...proud to have one of the first Mark I units
_________________________
http://mvgals.net - clublife, revisited.

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#3444 - 24/11/1999 09:35 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: dionysus]
altman
carpal tunnel

Registered: 19/05/1999
Posts: 3457
Loc: Palo Alto, CA
Amp ground ideally, but you may have luck by trying different points. Most of the time the amp's ground terminal is best.

Hugo



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#3445 - 24/11/1999 13:20 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: schofiel]
Elite M3
member

Registered: 15/09/1999
Posts: 101
Loc: Sunnyvale, CA, USA
The installer used the same AWG wire as the EMPEG supplied. I believe that it is 16 gauge. I don't have a voltmeter to test both locations, but it sounds like not even one person has been able to remove the engine whine from their BMW.

I don't know what the bonnet and braided strap are. Could you please clarify... And I don't know what ignition leads where used either. Sorry that I have no better answer's for you, but I do know the the RCA's that were used are not very thick and insulated. But from what others have said, even using the triple insulated RCA's, moving away from the power/gnd leads still didn't make that much difference.

I read another post that said that the way that a fellow BMW owner fixed his problem, was to use the grounded RCA's and ground it to the sled of the EMPEG. Does that sound like a good Idea?


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#3446 - 24/11/1999 20:03 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: altman]
dmoore
journeyman

Registered: 08/06/1999
Posts: 58
Loc: Houston, Tx, Usa
Both of my installs had residual noise even when the unit was paused. I solved all but the smallest amount by:

* Using the grounding leads AT the AMP(s) grounding point
* shielding the Sled from grounding
* covering the RCA cables with tape
* (most important) to ground the Empeg AT the Amp and NOT at the front

Just about perfect in both installs!


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#3447 - 25/11/1999 07:19 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
schofiel
carpal tunnel

Registered: 25/06/1999
Posts: 2992
Loc: Wareham, Dorset, UK
A few ideas:

-if the wire guage is the same, then so long as no other device is being powered by that cable, that should be OK. If the amp is being powered from the same 16 gauge wire, then it is unlikely to be sufficient. However, I would say that you should be more concerned with the earth wire gauge - make it as big as possible for both the empeg and the amp. The ground should only go to one point, near the amp. If it gives you any idea, I have used rigid single core feed wire for power and ground, the same stuff used to install electric cookers.....

- the voltage test is worthwhile. Twist your installer's arm and get him to do it. If he refuses, ask for your money back

- "bonnet" is the hood (engine bay cover). The electrical contact between the bodywork and the hood is frequently poor. If you connect the two permanently with a battery strap (braided=woven) then the bonnet lid acts as a shield against radiated noise from the ignition and charging systems. I have had good results on two cars doing this (not tried it on a Beemer though).

- you should be able to ask your dealer what sort of plug leads are on your car; if they are Bosch, they will state clearly on the lead "Radio Supressed" or carry the letter R after the lead number.

- you should really have the sled earthed to the car body, both for shielding and safety. Grounding the shield of the signal leads to the DC earth of the car is asking for it, I would have thought (earth loops, ground bounce spikes, horrible stuff like that).

- ask your BMW dealer about a supression kit, I know they used to sell them seperately.

_________________________
One of the few remaining Mk1 owners... #00015

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#3448 - 27/11/1999 10:35 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
borgcube
stranger

Registered: 09/06/1999
Posts: 36
Loc: Texas, US
Jason;
This sounds a lot like the problem I had with my install.

I moved the ground leads all over the car and could not get rid of all the noise. This was with an Alpine 4 channel amp. I finnaly gave up on the Alpine and went with a Kenwood that had floating ground inputs which got rid of all my noise.

You might want to see if the A/D/S line has a unit with floating grounds or move to a brand that does.

Kamau Wanguhu
[email protected]
http://www.BORGcube.com
_________________________
Kamau Wanguhu [email protected] http://www.BORGcube.com

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#3449 - 29/11/1999 10:01 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: schofiel]
Elite M3
member

Registered: 15/09/1999
Posts: 101
Loc: Sunnyvale, CA, USA
Well,

I was reading previous posts, and one person said that they had a Z3 with HK system and the empeg. And their solution to the engine whine was to use the grounding RCA's at the Empeg and ground it to the sled of the empeg. Guess what? IT WORKED! I was amazed, and the whine is gone. The only problem is still the speaker pop when the power goes on/off to it. I soldered a 1K - 1/2 watt resistor (only thing I could find at Radio Shack) between the ground and negative terminal of the RCA on the cable that EMPEG supplied and tested it at the deck, and at the amp, and still no dice.

The other thing is the digitized noise is still there. Even with the EMPEG on without the engine on or in my house, there is a digitized noise (you know, like an amplified mouse chewing on something). It is there with the playback of MP3's and if I switch over to the radio (through the AUX). I think that there is something not filtering within my EMPEG or something. Because nobody seems to complain about this noise. My roomate has an empeg, and he has question the sound too. Has anyone come accross this problem?


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#3450 - 29/11/1999 11:14 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
dionysus
veteran

Registered: 16/06/1999
Posts: 1222
Loc: San Francisco, CA
...I've got it too, but it's not bad at all.. Are you using the power filter that they provided?
-mark

...proud to have one of the first Mark I units
_________________________
http://mvgals.net - clublife, revisited.

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#3451 - 29/11/1999 11:18 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
altman
carpal tunnel

Registered: 19/05/1999
Posts: 3457
Loc: Palo Alto, CA
The resistor needs to be between the center and outer of the cable to help with the plop-on-poweroff problem, not between the outer and the ground strap. Give it a try.

Hugo



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#3452 - 29/11/1999 11:36 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: altman]
Elite M3
member

Registered: 15/09/1999
Posts: 101
Loc: Sunnyvale, CA, USA
Hugo,

By center and outer you mean?.....

Like this:

------------GND---------------{----RCA----}
------------NEG----/\/\/\-----{----RCA----}====
------------POS---------------{----RCA----}

Cause right now that resistor is between GND and RCA.
If I do put that resistor between NEG and RCA will that affect the quality of the music at all?

-Jason


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#3453 - 29/11/1999 11:38 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: dionysus]
Elite M3
member

Registered: 15/09/1999
Posts: 101
Loc: Sunnyvale, CA, USA
Yes, I am using the inline power filter. And I don't have it that bad either, but you can hear it pretty well with slow songs or if you just have the volume low (like <-32db).

-Jason


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#3454 - 29/11/1999 14:01 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: Elite M3]
altman
carpal tunnel

Registered: 19/05/1999
Posts: 3457
Loc: Palo Alto, CA
I've no idea what your diagram is: when I say between center and outer, I mean unscrew the top of the male RCA in the grounding lead and solder a 1k resistor between the only two connections that exist on the RCA plug.

Hugo



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#3455 - 10/12/1999 21:25 Re: Digitized Noise, Alternator Whine, Speaker Pop [Re: dmoore]
Mark Miller
journeyman

Registered: 21/09/1999
Posts: 69
Loc: Southeastern Pennsylvania
I also got rid of the alternator whine; and reduced the "pops" to acceptible levels, but even the "smallest amount" of audible noise is still annoying to me. Do you have ideas to eliminate it completely?


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