How to check amp distortion

[bluebear15]

I recently figured out that my body to frame ground and ground from secondary battery to body were bad and I fixed those. This was causing both my sub amp and speaker amp to have no power and after I got it fixed I went for a drive to listen to my stereo again and everything was good. The next day I was rotating my tires and checking my brakes and had the stereo on running off the second battery. I only had the volume at 14 and I start clipping at 22 so I wasn't that loud. After awhile I noticed some distortion coming thru my speakers. It was a lil crackle at first but then got worse and as u turned it up it got distorted more and cut out. I thought I had blown the speakers due to the ground problem. So I bought some new speakers and put one in and tested it out and still have the same distortion. I have 2 RockfordFosgate amps one is a p325.1 which powers my 2 12" infinity subs and the other is a newer (less than a yr old) p400.4 which powers my alpine type s speakers (components in the front doors and coaxils in the rear doors).

My question is how do I test for or know that the amp is giving me this bad distortion and that the amp is bad??

 

[blueflamed03]

pull amp and replace in it's spot with a known working on. Sounds like an amp issue. Check voltage AT the amp with the system on playing.

 

[bluebear15]

Ok I talked to a local audio shop to see what I could test and they gave me a couple tests. First I just hooked up a known working speaker directly to it and it still had distortion. So that meant that the distortion was coming from the head unit or amp. I took a head phone jack to rca cable and hooked it to my ipod and the amp. This was for ruling out that the head unit is good. I still got distortion so that means my amp is messed up. So gotta call tomorrow on it and see bout it under warranty.

 

[raptorforme93]

I took a head phone jack to rca cable and hooked it to my ipod and the amp. This was for ruling out that the head unit is good.

Ive never thought of that but thats a good idea. Ill have to remember that one!