So does the 6N23P-EV slot directly in without an adapter?
Yep, same pinout (and parameters) as 6DJ8.
You using a Voskhod or Reflector? Also, does it have the weird Russian timbre?
1975 Reflector. Not familiar with the "weird Russian timbre"; maybe sounds a little off in some indefinable way in the mids, or maybe it's just the contrast (more extension at both ends) vs the previous Heerlen A-frame making me think that.
Yeah, that indefinable off-ness in the mids. I thought some Fotons I tried had a lot of this.
I have been using the 6N23P (non EV) Reflektor for a good while in the SFD-2 and it's quite impressive. I think the upper mid can be a bit hot and upfront (just very slight) but the rest of the sound is excellent. Very linear from top to bottom and quite airy.
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