You might be better off on the Blue Circle forum.
Give them time to get back to you also, as the Blue Circle gang is on their first vacation since 1990. I think they'll be back around the 12th? or so.
My opinion, any preamp with its gain of low level signals, esp phono stages, should have external power supplies. For me, I hear a big difference in info, size and focus of soundstage.... I'd at least go for a BC3 (over the 21.1).IMHO.
so i've been quickly testing out both preamps over the last few days. not a lot of time spent, but here are my very quick first thoughts. i haven't picked up the focus audio speakers yet, so i'm currently testing them out with a pair of B&W CDM 9NT.
the BC21.1 seems to have more bass and quite musical.
the BC3 Despina seems more refined (?). things seem a little clearer and imaging a little better. the midrange si nicer. surprising, but it feels to be lacking a little bit of the bass that the 21.1 seems to provide more of. could this be a synergy issue since the bc21.1 and bc22 were designed together?
another point, i'm not sure it is supposed to be like this, but with the 21.1, i listen with the volume turned at the 7 o'clock position, whereas with the BC3, i have to listen at the 10 position. is this normal?
as well, i find the individual channel volume controls on the BC3 a little annoying.
so far i'm still not sure which one i prefer overall. leaning to the BC3 for now...
Do both units have the stock tubes? That would make for a more objective test. Do you own the BC22 mkI or mkII? It never occured to me that the BC21.1 and BC3 Despina might have different output impedances, but your experience indicates that might be the case. With most solid state amps I've partnered my BC21 with, the volume knob is set to around 8 o'clock. There have been a few exceptions where I needed to crank it past 9 o'clock to get the same perceived volume.
It should be fun test progression for however long your comparison lasts. Please keep us updated. I'll add that changing to WWII era NOS 6SN7s in my 1st gen BC21 resulted in monstrous improvements. In your case, I believe it would be 6922 tubes for both preamps.