Ok so before everybody hits me with SEARCH....my problem is pretty unique in the sound it is making.
I have a 5 channel amp and it is noise free...no problems. (except some minor alternator whine)
I have a 4 channel amp and it too was noise free. (except some minor alternator whine)
I decided to try a different 4 channel and after I installed it with no other changes, I now have a weird noise that I had originally but thought I got rid of by changing grounds and moving wires around. With the car off, not running, when I power up the amps and have the gains all the way down, volume all the way down, I get a medium/high pitch hum that after a second or two starts to play random tones. Sounds like a computer star trek hearing test or something. If I increase the gains...the noise gets worst.
This amp is brand new. It is a Soundstream Picasso Nano 4.320. My old amp is a Boss Chaos.
Now I have had this system noise since day one but after messing around with grounds and moving wires I was able to get rid of it with the Boss Amp. Now its back when the only thing I have done is change amps. ???
Need some help/advice. I have tried everything. It is really weird.
Could the Picasso 4 channel be bad or just built differently that it picks up noise more? Iam not sure how amps work to pick up on noise or filter it out.
My 5 channel (Planet Audio amp) doesn't have this problem at all. I tried my new Soundstream Ref 5.1000 amp and it to does not have the problem.
I do have an elaborate setup since Iam running a 5 channel and 4 channel amp. I have 2 sets of RCAs (front and rear) coming from my head unit going into a DSP/EQ. The DSP/EQ has 3 sets of RCA's that come out of it, 1 set is for subs and 1 set is for Ch 1&2 and both sets go directly to the 5 channel. The last set goes to a line driver/center channel processor as it's main input. The line driver/center channel processor then has 1 set going to the 5 channel as Ch 3&4 and 2 sets go to the 4 channel. This way I have not used Y adapters and all the splitting is being done actively by the processor.
With the line driver/center processor out of the loop I still get the same problem.
This has been driving me nuts. I mean I am grateful that I got rid of it with my old amp, but puzzled why with only changing to the new amp that the noise is back only x10 worst then when I started. Are amps picky and require you to move the grounds? Meaning one amp may like ground point A and another may like ground point B?
I dunno its a very strange sound..not a typical hum or hiss. This sounds more like I am hearing my cars computer through my speakers when I turn my amps on.
I also get alternator whine too with either amp. With the Boss I get less.
Iam using premium top notch monster cables.
I have my RCAs running down the center of my car and have tried moving them...doesn't help.
I have my power running all by itself down the right side of the car...it doesn't come near the RCA's except in the rear where it has to cross over them. I did hold the RCA's up at this position, it didn't make any difference. Noise still present.
I was going to try to remove the EQ just for ha'ha's but was still thinking...the probably had been eliminated to the point I can't hear it with my old amp but yet can with the new amp...so hmmm do I really want to try this. Sounds like the amp is faulty or just overly sensitive in amplifying the noise vs my boss unit?
Oh and I pulled both RCA's off the input to the amp. Problem when away. Of course I have no sound then at all though. So the sound is being introduced through the RCAs or a combination of something once the RCAs are plugged in. I tried using a set that was originally going directly from the DSP to the 5 channel, I still get the same problem out of the 4 channel but not out of the 5 channel.
