Pentodes small signal pentodes....... good for lots of gain like phonos and microphone preamps some may say they sport lots of noise for very low input applications they will need lots of tinkering 
Pentodes small signal pentodes....... good for lots of gain like phonos and microphone preamps some may say they sport lots of noise for very low input applications they will need lots of tinkering
The EF86 is rather special. It's more linear than many a triode and is quite quiet. Due to it's low gm, it is (IMO) not quite good enough for 1st gain block service in a phono preamp. OTOH, it's plenty good for 2nd gain block duty; just be sure place a buffer between an EF86 and anything resembling a difficult load. A common cathode 6922 section into a passive RIAA network followed by an EF86 2nd gain block could work out very well.
If you want to try a pentode in the 1st gain block of a phono preamp, the type I suggest looking into is the 6AC7. That pentode has the high gm needed to compensate for multi-grid partition noise. Definitely regulate 6CA7 g2 B+ at 150 V.
more precisely its 6Ж32П = 6j32p (equiv. EF86 small signal Pentode)
there's also a 6Ж32Б = 6j32b (which is a very different subminiature pentode, has nothing to do with your specimen)
6Ж32П
I would not put it at the entrance of the RIAA preamp, it makes much more noise than the EF86. For devices such as Quad-2 may be suitable.
I would not put it at the entrance of the RIAA preamp, it makes much more noise than the EF86. For devices such as Quad-2 may be suitable.