Yes the Fdeck enables me to Double quite easily. Part of it I think, is the 9.0 really likes UB too.
Using the Fdeck, it took my gain level up equal to my EB which allows me not to have to adjust that during swaps. The HPF allows me to suck some of the low end out on UB but leave it in there on for my EB. Works great.
Perhaps it's the Realist but I could not tell any asset by improved impedance using the Pre as not. I think the 9.0s input impedance works pretty darn good to start with.
I've seen a number of guys that do not like the tone of the Realist. On my Bass, through my Shuttle, into my Cabs, I love the sound. Full body, round, warm, and balanced is the best way I can describe it.
I can not believe I am so lucky as to have the 9.0 as my amp. It is such a joy not to be obsessing over amps any more. All the time and effort spent trying to optimize my sound and get the job done without compromise was getting old.
At some point I really would like to try out some of the Uber Cabs. Judging from how I feel about this amp I think I might be surprised. Might like to have two of the Ubber 2x10s.
Cheers to you guys at Genz Benz for making such great products. I'm one happy camper.