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Mini Pass Labs B1 Korg preamp.

Wardsweb

Renaissance man
My latest build is based on a Nelson Pass design found on the DIYAudio forums. Even though it doesn't look like it, this is a tube preamplifier. What looks like a glass IC is actually a Korg Nutube 6P1 Dual Triode. I purchased the PCB and NuTube from DIYAudioStore. The chassis is from China.

B1Korg01.jpgB1Korg02.jpg It runs on 29vdc. Fun little build and sounds nice.
 
That's cool, never seen a "tube" like that. What's with all the resistors around the knob? Is that some sort of "stepped" control, rather than the usual continuous pot?
 
That's cool, never seen a "tube" like that. What's with all the resistors around the knob? Is that some sort of "stepped" control, rather than the usual continuous pot?

Yes, the volume control is a stepped ladder attenuator. It was something I had laying around and tried. I have ordered a 50K Alps blue velvet pot to use in its place. The mechanical switching in this cheap ladder is too noisey for my liking.
 
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