hu hi-volt output

could someone clear up the differences of what this really does for you. i have had many headunits ranging from 2 volt output to 5 volt outputs and never really noticed a difference. what does this really do for you?   thanks ahead of time.....Eclipse 5435

US Amps Merlin MD2 x 2

US Amps Merlin MD42

Kicker Solo X 18"

MB Quart QSD216 x 2

The higher voltage signal input to the amplifier means that the amp will have to do less amplifying.  That is to say, if  amp A has a 4 volt input  and amp B has a 2 volt input, amp B will have to double the amplification compared to amp A.  The more an amplifier has to amplify a signal, the more it also amplifies any inherent noise that is carried with the signal.  In most cases amp B would have inferior sound reproduction.  Whether you hear the difference if you were able to do an A-B comparison is another matter.........if you have very little noise in the signal because, for one, the head unit is a finely crafted unit, you may not hear any difference.  I'm not sure about this part, but my bet is that a fine head unit that puts out 2 volts is better than a crappy cheap head unit that puts out 4 volts.  The difference is in the inherent noise.  If the crappy head has 10X the noise as the good head, that doubling of voltage will not be enough to equal the quality of the other head. Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

that makes sense thank you very much......Eclipse 5435

US Amps Merlin MD2 x 2

US Amps Merlin MD42

Kicker Solo X 18"

MB Quart QSD216 x 2