I just got my PPI PCX480 amp from UPS (thanks, Ebay!), and it has a button labeled -12db. The manual says push this button in if the head unit doesn't have RCA outputs. Does this mean what I think? Namely, this button is a built-in High/Low line level converter? Oh the joy that would bring me . . . No converters, no Blau adapter to fiddle with!

As you probably know, lots of amps have speaker-level inputs. From what I have seen, most of them have a separate input block for speaker-level in, and it usually accepts bare wire instead of an RCA-type plug.

But....

I just checked out the manual for your amp:

http://www.precisionpower.com/ppipdfs/pcxamps/multich.pdf

and indeed, it does use the RCA input jacks for speaker-level signals. So, it sounds like you'll be able to use the speaker-level output from the HU straight into the amp, provided you attach the RCA plugs to the ends of your speaker wires. IMO, this may be about the same amount of effort as using the Blau adapter or an external line-level adapter.

I'll let someone who is more familiar with the HU and/or amp comment on the sound quality differences if any :). Good luck, and please let us know how it turns out.

And I did read & understand the bit about the RCA connectors. It seems like it might be less hassle to use this "built-in" converter because a) no external converters to buy, install and troubleshoot if there's noise and b) no fiddling with the Blau adapter/stock harness.

I do hope to hear some comments on sound quality, too. Thanks for your input! I'm going to talk to the shop I *think* will be doing the install, and get their opinions as well.