Sindri, the power amp and monitor(s) plays a big part in the sound. The 'flatter' the FRFR system is the better. I have tried the following combinations with the 11 Rack:

Scenario 1: Marshall 80/80 Valve State Power Amp to Two Yamaha BR12 PA monitors - was missing frequencies and sounded a little harsh


Scenario 2: Marshall 80/80 Valve State Power Amp (Solid State) to Berhinger 15 band graphic eq (Stereo) to Two Yamaha BR12 PA monitors - Sound Improved but still not perfect


Scenario 3: Peavey Classic 60/60 (Tubes) to Berhinger 15 band graphic eq (Stereo) to Two Yamaha BR12 PA monitors - Good !!


Scenario 4: 11 Rack to EPSi IR Loader to Peavey Classic 60/60 to Berhinger 15 band graphic eq (Stereo) to Two Yamaha BR12 PA monitors - Really Good !!


Scenario 5: 11 Rack to EPSi IR Loader to Alto 112a powered speakers - Awesome!! \m/

I now own a Fractal AX8 and am still using the Alto 112a powered speakers and am just in love with my rig

So my advice is if you can try out the Alto's, or other similar quality system, I think you will be happy!