Trying to get rid of alternator noise.
My setup is this:
HU Pioneer dex-p99r(the old one)
Amp Velocity by Blaupunkt VR6000, a six channel amp.
Measuring resistance between chassis ground(negative battery) and phono input/or negative speaker terminal on the amp shows 1K ohm.
Measuring between chassis ground and rca shield is 1 ohm coming from the headunit
(it has 1 ohm resistors used as protection?)
Measuring between two rca shields show 2 ohm.
Does this mean that the headunit have common ground and the amp not?
Measuring between HU chassis and ground shows open circuit.
My setup is this:
HU Pioneer dex-p99r(the old one)
Amp Velocity by Blaupunkt VR6000, a six channel amp.
Measuring resistance between chassis ground(negative battery) and phono input/or negative speaker terminal on the amp shows 1K ohm.
Measuring between chassis ground and rca shield is 1 ohm coming from the headunit
(it has 1 ohm resistors used as protection?)
Measuring between two rca shields show 2 ohm.
Does this mean that the headunit have common ground and the amp not?
Measuring between HU chassis and ground shows open circuit.
I don't think that there are any 1 ohm resistors between the RCA shield and ground. 1 ohm isn't likely a problem.
Do you have noise if you plug only 1 or 2 RCAs into the amp at one time?
How bad is the noise?
Do you have noise if you plug only 1 or 2 RCAs into the amp at one time?
How bad is the noise?
It´s very low but still annoying. Most noticeable when starting engine and volume all the way down. It follows the rpm.
Uploaded the manual, on page 63 is the preout diagram I think.
filehosting.org - download page for pioneer_deh-p945r_dex-p99r_1_.pdf
Amplifier gain is not set too high, it states 8v fully clockwise on the amp, the dex have 4v preout and pot is set halfway.
I could try to groud the HU at the amplifier for starters. But why is there 1K ohm between rca shield on amplifier input and ground?
Uploaded the manual, on page 63 is the preout diagram I think.
filehosting.org - download page for pioneer_deh-p945r_dex-p99r_1_.pdf
Amplifier gain is not set too high, it states 8v fully clockwise on the amp, the dex have 4v preout and pot is set halfway.
I could try to groud the HU at the amplifier for starters. But why is there 1K ohm between rca shield on amplifier input and ground?
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Did you try setting the gains a bit lower?
Sometimes, very low level noise is difficult to get rid of. Did you try using a separate set of RCAs run directly from the head unit to the amp (over the seats or outside of the car) to see if it was quieter?
Sometimes, very low level noise is difficult to get rid of. Did you try using a separate set of RCAs run directly from the head unit to the amp (over the seats or outside of the car) to see if it was quieter?
I have a 6 channel rca triple shielded run on opposite side as powercable. Recently changed it and got rid of static/motor hum from the heaterfan.
Tried grounding the HU case, no difference. I´ve read something about common ground and floating ground components not function properly togheter.
Tried grounding the HU case, no difference. I´ve read something about common ground and floating ground components not function properly togheter.
do you have a good capacitor?
a 1 farad cap would greatly reduce the noise coming from the electrical components.
a 1 farad cap would greatly reduce the noise coming from the electrical components.
Yes I have a Stinger scp505 if I recall correctly. Where to put it, before the amplifier? Some put a capacitor on the alternator?
you place it connected in parallel with the battery and amplifier if i remember correctly.
should remove almost all noise 🙂 make sure the polarity is correct tho
should remove almost all noise 🙂 make sure the polarity is correct tho
Car audio equipment is almost completely immune to ripple/noise on the B+ line. A capacitor isn't likely to make a difference. I'm posting this because I don't want everyone with a bit of noise to go waste their money on a capacitor.
Generally noise is produced when there is a defective or poorly designed piece of equipment or the audio signal lines are too close to a 'noisy' component (sometimes the ECM or other 'computers').
Generally noise is produced when there is a defective or poorly designed piece of equipment or the audio signal lines are too close to a 'noisy' component (sometimes the ECM or other 'computers').
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