Sir you nearly blew your stuff cause you don't know how to set it up correctly.... 5v or 2v that should not be a deciding factor in buying a HU...Yea it does, if you have a HU with 2 volt preouts it means you have to crank the gain more to get the same output as a 4 volt HU which can bring in distortion. Nearly blew my **** up when i got rid of my Pioneer 2 volt HU and put a Alpine 4 volt in.
Most amplifiers can produce maximum power with a preamp signal from 4 volts to 200 millivolts, so if the system is properly set up there is no difference between a 2 or 4 volt preamp.Yea it is 2 volt headunits are cheap and have no were near as many adjustments as the higher end 4 volt HU. I've set all my car audio gear up, my one 12 hits 140 db on music not generated tones