Ok in my beater, 1987 Mazda 626, i installed my pioneer cd unit to replace the dead tape unit that was 20 years old. It sounds great, but when it goes up above about 20 in the volume, i get really bad amp clipping on the hard bass hits. I'm assuming i'm using the terminology right, clipping is when the speakers momentarily cut out during play, but it'* not really a distortion like the speakers being pushed past their limits? I know what that sounds like.. the farty noise. Now i had this SAME unit installed in my bonne, and it played loud just fine. I noticed the Mazda main power wire is somewhat tiny, could that be my problem? It'* just running 4 speakers, all 4 ohm, nothing real big. Any ideas?

upGrade your power wire to a bigger size to be safe i would go with 4 gauge

also make sure you have a good solid ground and that it is no more than 12 inches away from the amp

Keep in mind i'm talking about the amp INSIDE the unit, there is no separate amplifier for the speakers. Sorry i didn't make that clear.

ok what i said about and
or a defective unit

I would try to help you out but I am at a loss...sorry.

if ALL the speakers are making a crunching sound, you gotta turn down the bass. because the bass is what is causing the amplifiers insde to distort. If your hearing popping/farting sounds, then your speakers are overloading, If you hear both, you gotta turn down the volume!! the bass is what is hard on speakers and amps. try turning the bass down/off and crank it to see what happens.

I can turn the bass down to -1 or -2 at the same volume and i get slightly less, but still get the clipping i do with having the bass at +3 or +4.

but is it clipping or the speakers distorting? Either way, youll need a better deck, and speakers to get the bass and volume that you want.