Whining Noise

[jahphill]

Hey,

I just setup my new system..

Vibe SEK60 in the front, SEk69 in the back with Vibe A4 2000w amp (4 channel) annnd a Blaupunkt sub along with sony xplod BT5700U head unit.

I find a strange high pitch noise which changes with the speed im going and acceleration.. The noise is only present when I have the motor running.. I have googled this problem and the main cause of this problem is aparently the ground cable?

I changed the ground many times and this didn't help..

Yesterday while i was fideling with the cables I found the noise disapeared if i took out the leads which come from the headunit to the sub (mono out) powering the subwoofer..

I have chanel 1+2 bridged for the sub, and channel 3-4 for the rear speakers.

Im pritty sure the reason isnt because of low quality cables because I bought all the high end equipment along with wiring kits..

Any ideas what I can do? //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

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[IgnoreMe 5,000+ posts]

is this a pioneer head unit?

 

[jahphill]

noo a sony xplod BT5700U head unit

 

[IgnoreMe 5,000+ posts]

you have whining from your speakers, but when you remove the preouts to the sub the noise cant be heard through the speakers and they play fine?

 

[jahphill]

Correct o:

The noise only comes from the rear speakers (the ones connected to the amp).

Also the pitch of the noise increases as you accelerate.

 

[IgnoreMe 5,000+ posts]

yea its called alternator whine which is why the noise in creases with speed and is only present with the car on. i would try grounding the sub woofer rcas just temporarily connect it and see if it continues to introduce noise into the system.

look up "pioneer pico fuse" or something of that nature and youll see what i mean by grounding the rcas.

 

[djarmy2004 10+ year member]

possibly a bad rca connection at the HU.

 

[Bad4health 10+ year member]

Hey,
I just setup my new system..

Vibe SEK60 in the front, SEk69 in the back with Vibe A4 2000w amp (4 channel) annnd a Blaupunkt sub along with sony xplod BT5700U head unit.

I find a strange high pitch noise which changes with the speed im going and acceleration.. The noise is only present when I have the motor running.. I have googled this problem and the main cause of this problem is aparently the ground cable?

I changed the ground many times and this didn't help..

Yesterday while i was fideling with the cables I found the noise disapeared if i took out the leads which come from the headunit to the sub (mono out) powering the subwoofer..

I have chanel 1+2 bridged for the sub, and channel 3-4 for the rear speakers.

Im pritty sure the reason isnt because of low quality cables because I bought all the high end equipment along with wiring kits..

Any ideas what I can do? //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

the rcsa could be catching a light ground, the aftermarket wires could be too close to a factory harness(less than 18 inches), the battery terminal has oxy on it not being able to filter the ripples in the battery(clean the terminals), or the battery(or batteries) is not fully charged causing ripples in volts....or shit idk lol

 

[jahphill]

It might be a bad connection at the HU.. i had to tape the wires with the conector because it was queit loose.. but why would the rca cables for the sub effect the sound on the normal speakers?

I changed the rca cables round (rear speakers wth sub) just to see if it was faulty cables and that didnt change anything..

"IgnoreMe - try grounding the subwoofer rcas"

How do I do this? :S

 

[IgnoreMe 5,000+ posts]

It might be a bad connection at the HU.. i had to tape the wires with the conector because it was queit loose.. but why would the rca cables for the sub effect the sound on the normal speakers?
well because you have a single amp with normal speakers and the sub connected to it. introduce a shitty connection that might help interfere and cause the problems. no one really knows, we're just giving you idea at this point.

I changed the rca cables round (rear speakers wth sub) just to see if it was faulty cables and that didnt change anything..

"IgnoreMe - try grounding the subwoofer rcas"

did you look up how to ground your HU. "pioneer pico fuse" is probably a good term to try to look up. hell even google should show it. thats how you ground at the HU, same concept back at the amp really.

How do I do this? :S

also, maybe try swaping the wires over. instead of bridging 1 and 2 for the sub, swap over to 3 and 4 and see if anything changes.

 

[Qbenjamin 10+ year member]

It's more than likely the infamous alternator whine. What type of RCA's are you using?

 

[PaulD 10+ year member]

sounds like loop induction .....

 

[jahphill]

Thanks for all the replies.

I'll lookup about grounding the HU.

I checked the subwoofer connections at the HU and they are tight, nothing wrong there.

- Im using the RCA's that came with a heavy duty fusion amp wiring kit.

I played around a litle and this is what i have found:

When i start the engine with the boot OPEN, but then close it... the noise is less than when i start the engine with the boot closed.

So after re-positioning the subwoofer the noise became less alltogether..

Could it be that the subwoofer is to close to the speakers causing some sort of interference due to .. magnatism maybe? or is this not possible..?

 

[IgnoreMe 5,000+ posts]

whats a boot

 

[JuicyJeff 10+ year member]

not going to happen. How many grounds do you have in the trunk? If you have more than one you could have a looped ground which causes some stuff. But its the never ending troubleshooting of the alternator noise unfortunately