Sweeeeet...
 
Time to start savin'

The 5842 will be the driver tube. The Raytheons are great. I believe it could be one of those tubes where the plates are the same (or have very limited variations), but with different manufacturer labels. Less tube rolling unless you really want to find something exotic.

No one was heard this amp yet because it hasn't been put together. Anax has heard the Levi where the differences were with the Tango transformers and PS (which used 6D22 diodes instead of solid-state.)

I've heard Craig's personal amp, dubbed the "445" running 45 tubes instead with the same EP interstage, but with Lundahl OPTs and a Xenon tube glowie PS. I heard the 445 back to back with the 2A3.

Removing the interstage cap and replacing it with the transformer seems to speed up the sound and provide more clarity and detail extraction. Staging and layering are on another level. Dynamics are out of this world.

And yes, I had a chance to hear the 445 driving the Fostex BK-16 and Moth Cicadas. I loved some of the KR SE tube amps I heard at the show, but the 445 is even better, especially with the the layering and speed.

I think tube choice may be one reason to pick the BA, if one desired the ability to roll 6SN7 driver and PX4/300B tubes. The BA transformers are also sized better (that is smaller) for most traditional dynamic headphones. So maybe, just maybe you might get better detail extraction with Grados, HD600s, AD2000s, HD800, etc.

Those who have had owned the BA, including myself, have commented that while it does a good job with harder to drive orthos such as the LCD3, HE5/6, it's not optimal. I preferred the Dynahi, Mjolnir, etc. with even the HE500s.

It's possible the BA can get even better with the damper diodes in place of the 6X4s. I suspect it's possible that the 4x2A3 may eventually be a BA replacement. I think ultimately, it depends upon how the orders go.

The Leviathan killed the BA and all other headphone amps on resolution by far.  Whether swapping out the Tangos for EP changes that I can say that the IT should still pull more detail than the BA's cap coupled circuit.  The only reason I might consider the BA would be if I wanted the hyper-wide SS of the KR PX4s.  That's about it.  I'm pretty much over 6SN7s as drivers tbh, the 6BX7 is far better sounding anyway.  Technically the 5842 kills both of them with the only concern being microphonics, which for some reason in Craig's designs they aren't at all.  2a3's and 45s are far more microphonic than the 5842 even with it's high transconductance.  I tried banging on the damn tubes and heard practically zilch.

All 5842's pretty much sound the same, which is a good thing.  Leave it alone.  It really doesn't impart much of a signature.  They are the driver he used in the 304TL amp.

Its interesting that removing the cap can make that much of a difference. I am surprised that he would be able to produce something like the 4x2a3 for the same price as the BA when it is using an interstage transformer vs the caps.  Not to derail the thread too much but is it something to do with the parallel 2a3s that allows the use of the interstage transformer?   Could you use a capacitor instead if you wanted?