There is another similar valve to 1619. the 1624. Same specs, but 807 glass and anode cap. The sheet says refer to type 1619 for plate curves...

I can certainly relate to the metal can sentiment. Glowing stuff does add to the appeal.

I am working on various amp designs. I am trying to root out any hidden troubles, and find a best selection of parts.

Let's not forget the 300B. that's a pretty fine valve, and not much more demanding than a 2A3. Slightly bigger PS( KT88 sized ). An 8-10k chunck of output Iron will work well for both I think.

there is something to be said for PP, class A, DH triodes.

As to Guinevere gain, I do most strongly suggest punching another 9-pin socket in and trying the 12B4. Everything else is going to be transferable, save adding 2 more LED's in the cathodes. I do hate wasting gain...
regards,
Douglas

• CCS schematics