Tube Buffer?

Mike Hanson

I've realized that with certain music played at lower volumes, I like the euphonic distortion of tubes. Consequently, I've got the Cary SLP-2002 tube preamp in one of my systems, which pairs really nicely with the Modulus-686. This got me thinking: It would be nice if I had a tube buffer that I could occasionally drop into the chain.

Tom, I notice that you have two tube-oriented power supplies, even though you seem very focused on the veracity sound.
Does anyone have recommendations for a tube buffer module (similar to the excellent Universal Buffer) that could be used to add this magical quality? It would be a fun project.
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An alternative to the glowing glass bottles could be to add a diode in the feedback path around an amplifier stage. That'll give you a bit of low-order (mainly 2nd order) harmonic distortion.

Nelson Pass also has an H2 generator. It's a JFET amplifier stage where he gets the H2 by crushing the supply voltage.

If I was to design a tube buffer I'd probably go for the 6SN7. It's a very nice and linear tube and there's plenty of current production 6SN7s to choose from.

The ECC88/E88CC/6922/6DJ8 is a nice tube too if you're into the smaller 9-pin types. There's new production ones of those around too.