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RE: Low plate resistance vs. reputation for 'good tone".

Posted by Tre' on November 17, 2010 at 09:44:10:
I love the 6sn7. Used it for a line stage, the second stage in my phono preamp and as a driver for the 300b.

Now I don't have a single stage that uses the 6sn7.

A autoformer volume control did away with my line stage.

I use a 7119 for the last stage of the phono preamp as it has a lower output impedance and slightly more gain.

The 300b sounds better to me with a 5687 driving it. Miller capacitance is harder to drive than some people understand. 80fp of capacitance will have a reactance of only 20k ohms at 100kHz.

The 5687 CCS loaded driver stage has a output impedance of about 2k ohms while the 6sn7 is 7.7k ohms. 2k driving 20k is much better than 7.7k driving 20k.

Remember, if we can't have 100kHz unadulterated then we won't get 10kHz right. Yes I know that the output transformer won't get 100kHz right but that's not license to give up the fight. These things make audible differences.

P.S. It is a little weird having all these great 6sn7's I've collected and cherished over the years and now I have no place to use them in my system.

Tre'