Wow, I've been reading some posts about the bad sound of my G-22,000 that I'm thinking of selling it !!! Would it be the right thing to do? ... but I like your look so much ...! Here in Brazil there are some interesting models for sale:
AU-717;
AU-919;
AU-9500;
AU-D11;
AU-D11 ll
Some Alpha models (but these I do not want because they are 100v)
I really liked my 9090db receiver but I was looking for a more detailed sound with the same punchy bass as the 9090db!
All those amplifiers you have listed above are all in the same family of design except the AU9500.
Especially the AU-DII's, they have a similar type of sound to the G22K.
I owned and listened extensively to the G22K and the AU-DII.....I think they are similar sounding, but the G22K edges out in front, has a bit more "weight" in its sound. Both are very precise and detailed.
The AU9500 I found was a bit bloated in the low end and brash in the top end for me, BUT a very impressive amp and in its element reproducing rock music, great mid range.
They are grunty sounding amps....
The 9090DB and this would include the QRX9001/8001 as well (same power-amp driver) are a very nice evolution and development from the AU9500 in my opinion, it would be the perfect middle ground between the 22K and the 9500....
When I had my G22k I ended up using an active crossover and using a Crown Macrotech on my low end speakers, that gave me the actual weight necessary in my system whilst giving that amazing detailed mid range and top end I think is almost second to none from the G22K .
The pre-amp is not the issue, it was running my bi-amped system and sounded very very good, I was very happy with the sound...
If you like the AU9500 sound then you should probably stay away from those later Direct coupled Diamond differential designs.....AU-DII, AU-X1, 717, 919, 907 and that sort of thing.....
In summary, sounds to me like you need a 9090DB....