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Best/favorite CF NOS noval twin triode?

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What I am looking for is a recommended NOS twin triode in the "standard" noval pinout (12AU7 etc.) for a cathode follower.

I know about the standard forum recommended 6N6P (not NOS) and 5687 (different pinout). I know 12AU7 is often called an "OK" CF tube but I was wondering if there was something better. Larger heater draw or different voltage is no problem.
 
The figure of merit is gm, but you also have to consider desired drive current- a tube with 1mA of plate current won't drive a 1k load very well no matter how high the gm. For general purpose applications, it's tough to do significantly better than the ECC88 if you're limited to a dual package.
 
oldeurope said:
I think the input impedance of the next stage is 50KÙ.
Thus the ECC83 has the lowest loss in gain. (0,98 @2mA)
This is why I like the ECC83 here.

Kind regards,
Darius

At 2mA, you'll have some grid current issues with actual 12AX7s.

The gain for an ECC88 in this position is 0.97. The difference between that and a tube with a mu of 100 is less than 0.1dB.
 
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