I currently have a Alpine 9815 which has 3-4 volt preouts and I am thinking of gettin the new Alpine D300 pulsetouch screen. The only problem I have is the 2 volt preouts it has. The first thing I want in a system is SQ. How would it differ from 4 to 2 volts.

 

meh it's a difference that may or may not be noticeable given how powerful your amps are and the sensitivity they have. the easy solution to all of it is is to get a line driver and bump up the voltage. then it really won't matter the power the radio puts out.

 

I agree with Scott. I would try it first to see if it poses a problem with the SQ. If it does, then you could add the line driver.