Amp turn on wire whine

[WhiteYota]

Amps in sig - have everything wired up. Power ran down drivers side and RCA w/turn on wire on other side. Power and RCA's do not even come within a foot of each other. I left the turn on wire unhooked off of the 3800 where I do not have subs yet. Got a wild hair and decided to hook up my old sub box with 2 12's in it. When I hooked up the turn on wire to the 3800, the rest of the system started making a high pitch whine. Engine off, on does not matter. With engine running the whine changes a little with rpm. Amp grounds were grounded to bare metal with nut inserts put in where I could not get to the bottom side of frame rail. Both battery side and amp side of ground done this way.

Could there be enough draw on the turn on wire to introduce interference in the rca's where i ran them together. I read where it should be ok with 2 amps but anymore to wire in a relay for the turn on wire. I have not put in a relay yet but was thinking about it.

I also seen where the pioneer HU's have an internal pico fuse in the rca outputs - took it apart and soldered that - no change. Also grounding the RCA's does not help.

While I had the HU out - I did check with the RCA's unhooked from the HU - no whine

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[m4ick 10+ year member]

You said your amp is in your sig?

 

[m4ick 10+ year member]

Oh, I see, it said "subs" after it, thought that was a weird model number for a sub. Is that amp new?

A whine weather the engine is on or off would be an internal problem in the amp or HU usually. Have you tried connecting the amp in another car?

EDIT: Sounds like a problem with the HU. You did the right thing checking the fuse on the RCA shields but when you grounded the RCA shields, did you do it at the amp or the HU? You should do that at the HU, at the amp won't help. The amp usually ties the shields to the secondary center tap of the transformer and that is usually tied to ground with a 1Kohm resistor and a ceramic capacitor.

 

[WhiteYota]

Yes both amps are brand new - Tried grounding at back of HU.

The IA 6.4 came directly, drop shipped from Incriminator Audio while the AA 3800.1 came from SSA.

I have had the power/grounds/RCA's all in and gains set on the 6.4 (except the gain on the 3800) and have been using the HU and the 4 channel amp with the Focals for about two weeks, This is why I do not think it was anything else like grounds or bad RCA's or something like that. The only thing I did was connect the remote turn on wire to the 3800.

What got me was it does it when the engine is off, that is why I was wondering if maybe the 3800 is drawing enough on the remote turn on wire that the RCA's are picking it up.

Edit - fixed my sig lol

 

[m4ick 10+ year member]

The remote wire with the engine off is a steady 12.something volts. It WILL not cause whine, that is unless the HU is creating some noise on the REM wire. You could try disconnecting the REM wire crossing from the BAT+ terminal to REM to eliminate the REM wire as the problem.

Only AC current will whine. AC current comes from the alternator when the car is on. The only other places that whine can occur is in the power supply and the D-Class section of your amplifiers, they are pulse width modulated which basically means they switch to high and then low voltages rapidly. Ideally the class D section will switch well above your hearing range but it is not unusual to get speaker whine when the output filter capacitors fail.

Your amp at first glance appears to use the 3S Tech driver board, most likely the same one that is used in the Crunch GP3000 Pro. If I remember correctly that driver board WILL turn on without RCA signal which means that's probably not it.

I just realized, I have no idea where you're hearing the whine. Is it from your highs or on the subs?

 

[WhiteYota]

Only out of highs. I did some more checking and listening - I do not think it is alt whine. The whine does not respond as fast as engine rpms do. I have had alt whine in another car and this does not go up and down as fast with engine rpms as that other car did. I also tried putting in a relay into the rem line to the amps and that made no difference. I did disconnect the 3800 and the whine went away.

I was just thinking - where I put in nut inserts into the body for the ground, I looked at an extra and noticed they are aluminum inserts.

In case anyone is wondering what a nut insert is - Drill a hole that is the same size as the insert, then with the tool for them - it collapses the insert sandwiching the sheet metal in between it. The ones I used are for 3/8" bolts - put a bolt into it with the grounds and tighten it up. No worries about it becoming loose.

Here is one of the ones I used

 

[Jeffdachef 5,000+ posts]

Its where the amp is mounted probably, I've had that issue with my corolla where I had the amps mounted on my rear seat and just a loose screw gave me the exact same engine noise with the rpms like you are getting. I had to place a piece wood under it to keep it from touching steel and use T-nuts to secure it tightly. IDK what happened but it felt like the amp was grounding to the frame of the car and causing noise.

 

[WhiteYota]

[quote name='m4ick']The remote wire with the engine off is a steady 12.something volts. It WILL not cause whine, that is unless the HU is creating some noise on the REM wire. You could try disconnecting the REM wire crossing from the BAT+ terminal to REM to eliminate the REM wire as the problem.[/QUOTE]

I did try this but the whine was still there. I would not think it would be blown caps or anything else with the amp - when I got it it was clean with no markings on it anywhere on either the chassis or the rca connectors. Now I am not ruling out a defect but where this would be the first time I have had an amp over 1k, I want to check everything else out that I can.

@Jeffdachef - Yea the amp chassis would be grounded to the body floor (both amps are) where I mounted the 3800 with steel bar stock bent into a Z shape on each of the 4 mounting points on the amp, then with self tapping screws from the amp to the brackets and 2 on each bracket to the floor of the body. It is not touching the seat anywhere.
The IA6.4 would be the same but the brackets are in a L shape instead.


If it was alt or a ground issue - wouldn't the whine be there irregardless if the 3800 was told to turn on or not from the hu? I have not disconnected the power or rca's from it since I installed it. Only the REM wire (which would turn on the amp). With just the 4 channel amp there is no whine and it sounds awesome.

 

[m4ick 10+ year member]

Are you feeding the RCAs into the sub amp input then from the sub amp output to the highs?

If the whine is on the highs only when the sub amp is connected then the sub amp is where it is coming from (could still be wiring to that amp, but the cause is AT THAT AMP). The routing of the RCAs would be very important at this point.

 

[los33 10+ year member]

So it only does the whine noose when engine is off?

Have you checked your battery connections for loose wires or badly crimped wires?

Could also be fuse is not fully tight or even bad ground at the battery.

Last issue would be a bad battery sending bad current when really getting slammed by the sub amp.

Sent from my Z970 using Tapatalk

 

[WhiteYota]

Are you feeding the RCAs into the sub amp input then from the sub amp output to the highs?
If the whine is on the highs only when the sub amp is connected then the sub amp is where it is coming from (could still be wiring to that amp, but the cause is AT THAT AMP). The routing of the RCAs would be very important at this point.

The HU has 4 volt 6 channel outputs.

I have a 4 channel rca to 4 channel amp (highs) and 2 ch rca to sub amp - Both of the rca's (6 channels) running from front to back are on the passenger side with the REM wire for amps. I will also mention that the drivers side speaker out goes about 80% of this run back to the front and the rear passenger side speaker out goes about half way. Power is all ran down drivers side.

I thought that the speaker outputs with the rca's would be fine where there was no whine after it was all hooked up (except for the REM wire to sub amp)

Build log - http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/615221-2011-sienna.html

So it only does the whine noose when engine is off?
Have you checked your battery connections for loose wires or badly crimped wires?

Could also be fuse is not fully tight or even bad ground at the battery.

Last issue would be a bad battery sending bad current when really getting slammed by the sub amp.

Sent from my Z970 using Tapatalk

It is on both with and without engine running

These Battery Terminals that bolt directly onto the battery.

This Fuse Block is what I used on fuses. It has 6 total fuses of which 2 are for each segment out. I have it setup to where 1 segment (2 fuses) are on the 6.4 and I have 2 segments linked to 1 out which uses 4 fuses for the 3800.

And as far as bad battery - It does it without playing music and/or turned all the way down.

 

[WhiteYota]

I have been waiting for things to slow down here at work so I can pull it in and check for some voltage drops across the grounds - will post when I get it done

 

[Jeffdachef 5,000+ posts]

recheck the grounds again and see if moving the monoblock away from the 4 channel helps with the noise at all. If all else fails, you should do a head unit RCA ground

My current sienna right now, I have my 4 channel mounted underneath my front passenger seat on top of the carpet along with a piece of wood underneath and my monoblock mounted high up and far away from a body chassis in the trunk area and never ran into any noise problems at all.

I would say you have same source of noise I had in the corolla. The monoblock drawing current and causing noise with the two amps chassis grounded at the car's chassis.

 

[WhiteYota]

recheck the grounds again and see if moving the monoblock away from the 4 channel helps with the noise at all. If all else fails, you should do a head unit RCA ground

The 4 channel amp is mounted where you have the batteries located in your van (at least by looking at your build log I think that is where they are) and the sub amp is mounted to the floor under the 3rd row seats. So there is some space between them.

Yea I did ground the rca's on the HU but it does not have all of them on the back plate like the one you have in the pic. Only the sub out is on the back. The other 4 channels are pigtails

I also tried grounding the hu case

 

[Jeffdachef 5,000+ posts]

try unmounting your 3800.1 and place it on a piece of wood to see if you still have the issue.