Edmond,
Be very careful about not overloading the input section of your power amplifier -- a 9-volt preamp output could easily overload the input section of many power amplifiers. It could well be the source of some of the distortion you are hearing.
There is a reason that the pre-out levels (which do vary somewhat from one receiver manufacturer to another) are kept to a couple of volts, because most power amplifiers are spec'd to be driven to full output by a few volts. Check with Emotiva to see what input voltage your power amp can handle before the input stage starts going into distortion.
Does your Emotiva power amp have input level controls that would let you "tame" the input level from the preamp?
Regards,
Alan
