Car sound system doesn't sound clear at high volume.

Try lowering the gain on the amps. When your gain setting is too high, "clipping" occurs. You can only hear it at high volumes. If that dont work, check your speaker polarity.

Hello....sounds to me like you have way too much line level output comming from the signal source.....Maybe it's a cd/mp3 player....what ever it is.....If the system sounds better from your friend's sound source...Then nothing is wrong with your amp gain and head unit settings......your friend's signal source is within the correct input sensativity not to overload the rest of the components and create distortion.......If you have overload distortion from the source......all the amplifier gain adjustment in the world won't help you...If you turn the amp gain down.....You will will still be distorted at a lower volume...Which will be no better.....I don't know what the initial sound source is that you or your friend have...You didn't specify.....But on your's....check to see if there is a way to adjust the line level output......if so....try to reduce it...This will clear up the audible distortion problem you're having........good luck....