(to spark a little discussion in here)

Simply, my Alpine is too loud and my empeg is too quiet. What do I do?

I've got a bit of a quirk with my dual head unit install. It's empeg + simple Alpine AM/FM/CD deck. The RCA's for both go to a "source switcher" which runs one set of RCA's to the amp.

With the gain on the amp set wherever my installer set it, my empeg set to -20dB is decent but a bit quiet. My Alpine set to 18 (of 30) is comfortably loud. At 0dB, I can tolerate the volume of the empeg. The Alpine, let's just say I've never gone to volume=30 for fear of damaging my (stock) speakers and my ears.

Maybe I shouldn't, but I think this is a problem. I want my empeg to be barely tollerable at 0dB. I'm convinced that a range of volume like that would allow me more accurate EQ settings (so I could make them -dB instead of all +dB like I have now because it's too quiet). And I want my Alpine to calm down a bit, so I don't kill myself if I accidentaly spin the volume knob.

But there's only one gain on the amp. What can I do:
Could the installer have hooked up the Alpine output from the speaker level outs? No, that's impossible, right?
Could I get a de-amplifier for the Alpine so I could get more gain on the amp?
I thought I read reasons for max gain settings on amps. Any links so I can avoid hurting my amp?
Or am I just using my empeg incorrectly as always? Am I SUPPOSED to only have audible sound from -20dB to 0dB, leaving the myrad of volume increments below -20dB to be too quiet to hear? (no, it's not broken, just too quiet).

Eventually, I want to add better speakers and a sub to my system. But I think I should get this worked out first. Thanks.