So here's the Astra guy ;-)
My modulator is a
Farenheit EFM-02
You can find it here: (or try an other search)http://www.thezeb.com/caraudio/poweracoustik.html

My install is different: I didn't mount the sled; my empeg is connected to the mod by the 1v line out rcas.
I put the gain to the max and it works fine.
I heard the same song on my cd hu and on the empeg, quality is better with cd for sure, but there's not a big difference. It's a very good temporary install.