Output / Input Voltage Question


If I have a preamp that outputs 1.5v, but the amp's input is .5v, would this be the reason I don't have much headroom when I turn the volume up?  What is an ideal voltage match for preamp/amp combo?  Sorry if this is a dumb question.  Electrical stuff is not a strong point for me.
terrapin77
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Can't go past 40% volume without being way too loud.

Why didn't you say so? All this voltage stuff is irrelevant. Your problem is you think that where the volume knob is pointed means anything at all. Relax. Where the volume knob is pointed means nothing at all. Or if you want you can tell people your amp is so incredibly powerful look how loud it is and the volume is barely cracked open. But seriously, where the knob is pointed is utterly irrelevant.   

This is in stark contrast to the numbers on the dial, which are incredibly important.  https://www.youtube.com/watch?v=4xgx4k83zzc  

That's a joke, son. (I have to say that because audiophiles have no sense of humor.)

@millercarbon LOL!!  I read all of these posts about voltage and impedance and I can't wrap my head around it.  Add speaker sensitivity into the mix and I'm completely lost. 
I'm in the same happy boat where noon is off and 5 o'clock is LOUD. Not a big deal except the less carbon track the signal has to pass through, the better. That's why a switched resistor type is better.