Looking for nuvistor pre-amp preamp schematic please. 6CW4?

[calico88]

anyone seen good/best nuvistor 6cw4 or better nuvistor schematic for preamp ?

anyone build one ? how is the sound quality compare to bigger/glass tube ?

cal

[jackinnj]

rP = 5.44k, gm = 12.5k umho, mu=68 Cgp = 0.92pF - from the 1964 ARRL Handbook -- I used this tube in a VHF preamplifier.

[SY]

Very, very, very microphonic. And not terribly quiet. They look cool, but are hardly worth the effort.

[calico88]

any Schematic ppreamp for 6cw4 ?

cal

[wiligruen]

Hi,
there is one schematic published by tnt

http://www.tnt-audio.com/clinica/preamble_n.html

[mach1]

cal,

I believe the TNT website has a Nuvistor linestage posted somewhere.

However, I couldn't recommend the 6CW4: the gain is way too high for a linestage and the plate curves http://frank.pocnet.net/sheets/049/6/6CW4.pdf
are decidedly non-linear.

I think half the perception problem with nuvistors is due to Musical Fidelity using them to suck magazine journos into thinking they had made great advances in the art of amplifier design (a bit like Tim de P using 12AX7s as output tubes). If you want to go small there are some really good subminiature tubes around (eg 6111, 5977) at reasonable prices that would make excellent linestages. I believe Quad use the 6111.

pm