Stereo & Electronics - pioneer

I was wondering if someone can tell me what the diference is from a 4volt and a2.2 volt on rca outputs both are mp3 player thanks

The difference is how much gain you need to apply with an amplifier to get an equal amount of power out. Other than a potential yet inaudible difference in signal to noise ratio (SNR), just the gain setting. Both voltages are in the range that basically any amp will work optimally.

So if that wasn't clear, higher pre-out V = better, but as mentioned, both will do the job for a single amp (if you plan on running multiple amps off of one pre-out for some reason, get the higher voltage pre-outs).