B1 with Korg Triode

6L6

Moderator
Joined 2010
Paid Member
attachment.php


attachment.php


A couple of pieces of two-sided foam tape under the NuTube is helpful.

attachment.php

This switch is very nice, but quite small. The inputs will be taken to the outer ring of terminals, the output is the center pins.


attachment.php


To give you an idea of the size, the wire used is the twisted pair from inside a CAT-5 networking cable. (One of my very favorite sources for good signal wire.) The copper conductors needed to be smushed and shaped a bit to fit inside the solder holes.

attachment.php
 

Attachments

  • IMG_0581.jpg
    IMG_0581.jpg
    474.8 KB · Views: 1,392
  • IMG_0582.jpg
    IMG_0582.jpg
    626.6 KB · Views: 1,415
  • IMG_0578.jpg
    IMG_0578.jpg
    899.5 KB · Views: 299
  • IMG_0579.jpg
    IMG_0579.jpg
    501.9 KB · Views: 312
  • IMG_0576.jpg
    IMG_0576.jpg
    871.7 KB · Views: 1,409
  • IMG_0577.jpg
    IMG_0577.jpg
    845.5 KB · Views: 2,217
  • IMG_0589.jpg
    IMG_0589.jpg
    975.3 KB · Views: 1,412
Last edited:

6L6

Moderator
Joined 2010
Paid Member
Chassis wiring

attachment.php


attachment.php


Yes, I used a lot of different types of wires. I wanted to try a few different things as I just received a few of the various cables. It could easily and quietly all be wired with the Cat-5 wire if you like. Use what you have on hand.

Please note that I wired my outputs IN phase. Nelson's article and the video mention that you might want to wire them out of phase for max effect, but you can of course do that at your speaker wires quite easily as well. It's up to you how you want to do it.
 

Attachments

  • IMG_0587.jpg
    IMG_0587.jpg
    668.5 KB · Views: 1,416
  • IMG_0586.jpg
    IMG_0586.jpg
    865.6 KB · Views: 251
  • IMG_0584.jpg
    IMG_0584.jpg
    545.2 KB · Views: 1,391
  • IMG_0585.jpg
    IMG_0585.jpg
    529.4 KB · Views: 375
Last edited:
Nominally I’d suggest placing the transformer away from the potentiometer. :)
Thnx.

There are a few ways to jigger the positioning, including putting the power supply outboard. That's to be determined. Maybe the power supply on/off with the hole on the right with the Korg board on the left and the volume and 10k potentiometers on the left.

I am a rank beginner, so I am sure things will get worse before they get better.
 
The above photos conform to this schematic; the XMAS version --

728470d1547315648-b1-korg-triode-xmas-nutube-diy-gif

You say build conforms to xmas schematic but:

1) It appears you used the 1K gate stopper resistor between the Korg plate and the output JFET, as found on the PCB. If following the schematic, would it not be be a jumper instead?

2) It's hard to read the band colors in the photo for the post-output cap resistors. Are they the PCB values or the schematic values?

I have read in previous posts that the above choices are optional. Just wondering if there are recommendations one way or the other. Seems like the 1K plate to gate would make things more stable but possibly change the sound a bit. The 100/33.2K vs 221/332K choice seems less significant although 100/33.2K again seems a more stable choice.
 
Question from a "kit" builder: Two PCB's would make a balanced version?

I asked before:

O.K.
Here it is an other question.
As you probably know, I'm a Wacky man, with my balanced mania.
I will intend to use two B1 Korg Boards balanced.
What will be then with second harmonics?
If understand well, in this case second harmonics will extinguish each other.
It will kill its charming soundscape.
Any thoughts?

It is for sure, I think.
But what will be happen to second harmonics?