[ramie2400]

yaar i am using a Pio AVH-4950dvd In-dash,it gave me a whine when i had re-done the system fo the second time i grounded the same way and its puuurrfect till now no issues at all.

[Tool]

even i don't know bro ramie...
maybe its a grounding loop issue and the ripple/whine is coming into the HU from the cars wiring harness?
If the Hu is still grounded using the wiring harness or directly behind it, then this would make no difference because of the higher resistance at that point of grounding.
basically in that diagram the RCA's get grounded.. but maybe the problem is that the HU is not grounded properly ?
im confused too bro.. have no idea.. just taking a guess..

[ramie2400]

till what ive noticed there are 3 kinds of whine.
1)there is a constant aeroplane kind of sound at low volumes.
2)is the Kat-Kat sound which makes your speaker/woofer coils bounce
3)where the whine is too loud with Kat-Kat sound and the subwoofer is sucked inside when you play it (which is very dangerous as it might blow the subwoofer)

I know its a serious issue of grounding,it can even happen if you have the power cables close to the ground cables,or your using a very thick wire as a Remote wire???

[amit_mechengg]

the whine vanishes if u put the AMP in LPF mode. it occurs only when u r running it in full mode. the woofer doesn't create any whine as it is running in LPF mode. even the woofer is not making kat kat sound. its just the speakers making all sorts of funny noises.
well i have spent a lot on wiring, rework and labour. till now i have got the wiring done 3 times. also tried with JBL rca cables.

[Tool]

then i assume its happening in HPF also.
cant think of anything else bro...
try the Hu ground fix.If nothing works.. wrap your power wire and crossovers in foil and see if that makes a difference.
thats the last option i can think of since you have tried pretty much everything else.
please keep us posted bro..
big boom

[amit_mechengg]

i think some audio experts and installers should give their opinions here. SAM sir, LBM , Bass & Trouble

[Bass&Trouble]

Amit, try this.

Remove the head unit from the dash and take it to the trunk. Power it up there and connect it to the amp using the same RCA cable being used currently. If it persists, then change the RCA cable to another good quality one. In either of these two cases, the noise should go away. If it doesn't then its something to do with the amp.

[alto99]

I have a question for experts
Is the whine dependent on the proximity of the HU to the engine? I ask this because
1. amit has mentioned in his first post that the problem first occurred when the HU was fit in dashboard.
2. I am also facing this same problem (alto+pioneer) but while playing cassettes . Whine is eliminated when I remove the HU from dashboard and comes back as soon as HU is put back.
Though it sounds stupid it seems to me that the vehicle alto is more of a culprit than the wiring/ground.

@amit If possible can u eliminate the amp and test may be with only front speakers with the HU in dashboard?

PS: In my case whine may be because the cassette player head picking signals from the engine. I had read some solutions like shielding the player from engine but never tried that, but do similar problems exist for modern cd/usb players as well? I hope not because I want one!

[navin]

Originally Posted by alto99

I have a question for experts
Is the whine dependent on the proximity of the HU to the engine? Whine is eliminated when I remove the HU from dashboard and comes back as soon as HU is put back.

could the chassis of the HU is touching something when it is put back.

[alto99]

Originally Posted by navin

could the chassis of the HU is touching something when it is put back.

Haven't checked that but I remember even if I bring it close to the console it starts whining. I will reconfirm this though but it will take some time.

[amit_mechengg]

Originally Posted by alto99

I have a question for experts
Is the whine dependent on the proximity of the HU to the engine? I ask this because
1. amit has mentioned in his first post that the problem first occurred when the HU was fit in dashboard.
2. I am also facing this same problem (alto+pioneer) but while playing cassettes . Whine is eliminated when I remove the HU from dashboard and comes back as soon as HU is put back.
Though it sounds stupid it seems to me that the vehicle alto is more of a culprit than the wiring/ground.

@amit If possible can u eliminate the amp and test may be with only front speakers with the HU in dashboard?

PS: In my case whine may be because the cassette player head picking signals from the engine. I had read some solutions like shielding the player from engine but never tried that, but do similar problems exist for modern cd/usb players as well? I hope not because I want one!

hi bro,
the whine is mainly because of the amp. if u dont put any amp and directly connect the HU to any of the speakers the noise wont come.
and i have tried by removing the HU from the dash. But still the noise persists. i tried with different new brand HU. still the noise doesnt go. today i will ground the HU to the same common point where the amps are grounded. lets see what happens. will also try to take the HU to the trunk.

Originally Posted by navin

could the chassis of the HU is touching something when it is put back.

the alto indash bay is so cramped. when the hu is put back it just touches the mounting plate behind the dash. i have put a rubber plug so that the HU bracket is held tightly and the threads dont touch the plate.
i have grounded the HU to the metal behind the dash.

[Bass&Trouble]

While at all this try a different RCA cable also.

[amit_mechengg]

Originally Posted by Bass&Trouble

While at all this try a different RCA cable also.

yes sir sure. with all this work going on from morn 10 to night 9.30 i couldnt spare time to fit the compos. also spent a lot. running out of budget

[Tool]

any updates bro ?
did you try it today ?

[amit_mechengg]

Originally Posted by Tool

any updates bro ?
did you try it today ?

no dude i couldnt. didnt get time. i have come home at 9.15 PM from my office. i will take long speaker wire and use it for grounding purpose of HU to the common point amp grounding.