Anyone listen to Zu Audio's Definition Mk3?

Yes, the Frankensteins are sadly gone. They didn't match well with the Pendragons, but they would be an ideal match with the new Definitions' nano drivers. You are spot on and I've been on the lookout. The warmth of the 300b would be IMO ideal. Having said that, the PX-25 is very nice and paired with my current system, I have a very nice, musical presentation with a very wide and deep and holographic soundstage. A little more warmth is the vocal range and I would be very happy!

Morgan,

Looking at the tube compliment of your amps I see 274Bs are acceptable. Buy a simple pair of Shuguang 274B rectis online--you can get them for $10 each if you shop around, and see if that brings you exactly what you're looking for. I'm blown away by what that cheap recti is doing in my AN211 as is a buddy of mine with them in his Tubeguru F2a monoblocks.

Thanks Gopher. I'll give that a try!

Morganc,
Do the nano drivers render the Zu more neutral or revealing than the Pendragon ? Was the Frankenstein 'warmer' with the Pendragon(is this speaker perhaps voiced warm?). The Frank`s sound does change significantly depending on choice of 300b selected.I`ve used EH golden grid,W.E. reissue version,Sophia Royal Princess and Takatsuki-TA 300b. Each tube actually makes the Frankenatein sound like a different amplifier.

The Sophia RP is excellent,the Takatsuki is simply sublime!
Regards,

Morgan,

I have the generic shuguangs, but after further discussing the tubes with 213cobra, it appears the "Preferred Series 274B" that tubestore sells for $30 have a stronger vacuum and may be 'better.'

If it were me I would drop $20 on a generic pair immediately and if I liked what I heard, keep them as a backup and get the better ones when I got around to it.