Alright i am looking at a car deck right know and in the feature of the deck sometime i see 2 volts, other 2.2 and i recently found one at 4 volts. What do the volts do? does going from 2v to 4v make a big diffrence?

 

more volts sent to the amplifer the better, gives a cleaner signal to amplify

 

will you see the diffrence between 2 and 2.2? or between 2 and 4, should a pay 110$ just for this feature, and other esthetics like motorized face

 

The answer to all of your questions is NO..........

 

Theres really no benefit from higher voltage imo, they sell it to ya cause everbody thinks bigger is better, more is better etc, ive used 2 v decks,now i have a 4v deck,only diff i found is were my gain is set, no audible difference that i can tell.

 

Immunity to noise. The higher the output voltage on the deck = the lower the gain setting on the amp. It is indeed a good thing.

 

doesent seem to be audible to me? is it better for sub amp/sub as far as distortion is concerned? Or does it help the amp to not have to work as hard?
I myself have an alpine 9815, the sub output is not 4v i noticed when hooking up the rear rca to sub amp,the sub was louder. Ive read the 9815 doesent hit 4v on the sub out till 30+ volume while the fronts and rears start to distort round 27-28 volume. That makes no sense at all to me!

 

^ The output voltage is only half the picture..... you also need to know the output impedence to be able to determine if the deck truly could drive the rated voltage into the next device. For example: a good output impedence is about 100 ohms and a even better is *10ohms. (*usually need an outboard dc to dc converter)

Also a 4V player with cheap parts might not sound better then a 2V player with good parts.

 

I agree! Most amps have what they called an internal impedance. This resistance is basically related to distortion level - the lesser the better. If you look at ohm's law - V=IR or R=V/I, in other words, the higher the volatge the lesser the resistance. As a result, you'll have less distortion level or better audio quality. You may not noticed it at low volume, but certainly audible on high volume. That's the whole point of having an amp in the first place (louder) but you may want to maintain better quality at the same time and that is by going with a higher preamp voltage head unit.