Phonodude 12ax7 version

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I can't reach the guy who help me to build my first tube project (Phono Dude 12ax7 verion) so I need some help..

I almost finish, last night I do all my measurement and I just need validation before going foward on this project I start since 2012 !!!

Thanks.
 

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PRR

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Joined 2003
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...need validation...

What are your concerns?

The DC voltages look reasonable. All tube-work is +/-20% at least. SPICE models often disagree with real tubes. Your B+ is way within reason (thanks to the bigger 30K) and the gain-stages' mid-points sit near the middle (a bit lower in the first un-biased stage, as expected).

Heater-cathode voltage breakdown? Your heater arrangements are not shown, and 0V on 1st cathode to 170V on 3rd cathode is a large spread.

Have you checked for DC on the output? There will be a turn-on spike but it should settle to much less than a Volt after a minute.

Put signal through it; that's the only true test.
 
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