thanks - I'm leaning towards the X5 but wanted to see if anyone else went through a similar decision process recently - I was originally looking for a horn based speaker, the X5's AMT is quite hornlike with it's waveguide. In general, I'm not a fan of most AMTs as I find them unnaturally bright. The Carver's ability to tweak the voicing with the bias in addition to input stage tube rolling is definitely a plus. Curious - what are you using for tubes? I have a set of NOS Mullards that have replaced the stock TungSols.
I use Telefuncken ecc83's from the 60's. A detailed and airy tube and I turn down the bias and get that great detail plus the soundstage is huge when I set at about 85 millivolts. There are tons of NOS numbers that replace the 12ax7 number. None of the new production tubes I've heard, and certainly not the stock ones that come with the Carver do it for me.
Substitutes: ECC83, 12AX7A, 12AX7WA, 7025, 5761,6057,6681,7494,7729, 7025#, ECC83#, 6L13, 12DF7, 12DT7, 5751, 7025A, B339, B759, CV4004, E83CC, ECC803, M8137.
The GE 5751 is a bargain basement musical giant! And there is a Mullard cv4004 that is widely lauded as one of the most sought after replacement but the price......