B1 with Korg Triode

Thanks for sharing your thoughts. Based on your findings, the standard B1 would be of great interest to me. Although, extra warmth is welcome by some -- I prefer neutral and dynamic.

Keep in mind standard B1 has no gain. If you need gain, you can either add step up transformers or possibly wait for NuTube version of B1 and adjust grid bias for minimum distortion, which is plate voltage at somewhere around the 1/2 supply point. I'm currently listening to Pete Millett's circuit (which uses mosfet buffers) at a plate voltage of around 9.5 VDC on a 24 VDC supply. Pretty heavy on the 2nd harmonic.
 
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Here is the operating stuffed copy.

It uses the Toshiba 2SK370, which is the 170 in a slightly different package.

I am considering two versions of the board, with the Toshiba/LS parts
and with the cheaper Fairchilds.
 

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Ok......I was thinking if only one version should be handled (the expensive) then this version would be a little bit cheaper than if two versions should be handled. I would go with the expensive (best components). Compared to the time it takes to finish such an amp.....the price difference is not important for me…...but maybe it is for other…..
 
It would probably be something like the difference between $49 and $99 in the store.

I think 50 bucks is significant in a preamp circuit. Is this just a pinout thing plus possibly some resistor values? If it comes down to only making one board version available, I vote for the LS pinout and I can cross the legs on the J113s if I decide to use them.
 
Done. New artwork will accommodate DGS and DSG pinouts and
current source degeneration resistors on the buffers.

A Big smile from this particular DIY enthusiast. Lacking an Audio Precision, it would eventually be a helpful starting point to know the recommended plate voltage for minimum distortion, unless Ea = half the voltage present on the supply side of the plate resistor is good enough.
 
Just my 2 cents:

I think the true value in DIY HiFi is to create high end audio on the cheap. For those just interested in the savings side and not the high end, there are better alternatives; even kits that are pre-assembled (like Parts Express, etc). Pete Millett has his own schematic and board for which people can source their own components. When considering a $50 difference, I think most would take the plunge for the higher end kit.

So here's one vote for the high end option. I am hoping for a way to get notified when the kit is for sale.
 
A Big smile from this particular DIY enthusiast. Lacking an Audio Precision, ..............

Lacking and Audio Precision as well.....
i use a UCA202 DAC (20$) with my old laptop to do the measurements

Softwares are: Audio Tester, REW and Arta

After having destroyed two DAC i built an attenuator following a schematic by DM JOFFE (?) i found somewhere here around. Helps a lot
I really would want some means to see the distortion when setting the bias for the Korg triode. The changes in distortion pattern are a lot! In my case i use a setting of well out of half supply voltage.
 

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Just my 2 cents:

I think the true value in DIY HiFi is to create high end audio on the cheap. For those just interested in the savings side and not the high end, there are better alternatives; even kits that are pre-assembled (like Parts Express, etc). Pete Millett has his own schematic and board for which people can source their own components. When considering a $50 difference, I think most would take the plunge for the higher end kit.

So here's one vote for the high end option. I am hoping for a way to get notified when the kit is for sale.

Although the B1 is on PassDIY, it sounds like maybe this will be sold through the DIYaudio store. Just get on their emailing list. They usually send out new stock updates.