B1 with Korg Triode (B1K) Preamplifier PCB + Fairchild JFETs
At Burning Amp Festival 2017 Nelson presented a version of a pre-amp using the Korg Nutube dual triode. We now have the latest version of this circuit available in the store complete with Fairchild JFETs and all directly supplied by Nelson Pass.
Please check the following links for more information:
- PCB (5.5" x 3.25", mounting holes 5.0" x 2.75")
- 8 Fairchild JFETs and tweaking resistors (all direct from Nelson) for just $25
What's not included:
- The Nutube. You will need to supply your own Nutube, and they are available from the diyAudio Store separately for $49.99.
- All other parts required to make the project
- The board is compatible with both DGS and DSG JFET pin orientation. Use the correct holes for the JFETs you are using as directed in the article "JQ1,Q2 is used for the Fairchild J113's and the KQ1,Q2 fits the 2SK170, 2SK370, and LSK170 Jfets."
Built with dact attenuator , non stock components and duelund wire. Few amtrans resistors as well. Musical ,smooth and lifelike with the bonus to adjust It at your taste. Again a breathtaking circuit!
Fun and very easy kits to build i built 4 different revisions from basic to upgraded PSU with Clarity Caps. Definitely a difference in sound but all have sounded great. No issues with microphonics. I just use a type of sound deadening matt on the inside of the chassis and put some around the standoffs.
Super quality as always from the store. Great kit and very nice relaxed sounding with lot of laynack character. Highly recommended for those who want to try something different that traditional linestage amplification.
I built it in a different box, with remote attenuator (Chinese motor operated ALPS potentiometer)
Being afraid of "too much of a good thing" and having a triode based phono stage, I equipped it with a bypass, so I can run the signal straight or through the Korg, the picture shows the look at the test phase.
As far as I can tell until now, the Korg makes the music sound better to me, but I can switch between streight signal pass and through the amplification.
Once again, would like to thank the designer Mr. Pass and the kit supplier, a wonderful preamplifier! Not to forget the F6 which we at home enjoy on every day basis
This is a great preamp kit designed by Nelson Pass, comes with exceptional quality parts, and easy to build. The Korg Nutube 6P1 tube is not just a very cool device to look at, but also a very low power consumption vacuum tube which made it a perfect solution to convert it as a battery-powered preamp. Unlike a regular vacuum tube preamp, the Nutube 6P1 is not interchangeable. Although tube rolling is not possible to this preamp, Nelson adds a feature to adjust audio harmonics by a pair of trimmer pots each controlling the left and right separately. I can experience a different sound stage and 3D space by adjusting the value of the trimmer while the amp is powered on, how wonderful!
The kit already comes with audio grade electronic parts. Chassis is simple but elegant and solid, high-quality parts from Italy. I completed the kit with original parts which sounds very good already, later changed a few electrolytic caps with some polypropylene from the signal path suggested by the group member, this further improved the sound quality.
This little preamp kit is easy to build with lots of fun to discover. Worth every penny!
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