KORG Nutube 6P1: a mini vacuum tube triode

Haven’t seen this discussed here yet but this looks like an interesting piece of technology: https://korgnutube.com/en/

It’s a small, low-voltage, dual directly-heated triode device. It’s manufactured like a vacuum fluorescent display, just with “one pixel”. Despite the size, it shares audio characteristics with traditional valves.

While you can buy the triode yourself for about $50, it’s been steadily appearing in KORG products since its 2016 release. Some interesting ones:

Volca Nubass

nu:tekt OD-S Overdrive pedal kit

The pictures of the last one is actually a unit that I assembled. The overdrive is suitable for both guitar and synthesizers, can provide clean boost as well as pleasant low-gain distortion. Thanks to the low-power nature it’s perfectly happy with a 9V battery which makes it a unique stomp box. If you’re interested I can make some demos.

It would be cool to see it used in eurorack modules or in conjuction with NTS-1 or the bigger Minilogue xd. There’s already an interesting DIY project with this device: a preamp. Note that unlike the OD-S, this is an actual soldering project.


This is cool thanks for sharing! Definitely interested in demos if they’re not too much trouble :slight_smile:

If you want to see an example of this technology in a modular application, the Plankton Spice contains two circuits that use the Korg NU Tube


How’s that for a demo, this time driving the Circuit Mono Station:

I’m not a pro at this so bear with me here. Open to any feedback you might be having! :slight_smile:


I think it’s the same as the tube in the teeny tiny vox mv50 heads. I had one and it sounded massive. But was the size of a small handbag. Great bit of kit. Just too quiet against my other guitarists 5150 #shocker

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Vox is owned by Korg so that would make sense…

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That was a great demo, thank you! You could be a pro-synthfluencer, someone send rplktr a subharmonicon! ^ _ ^

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This is off topic here but I do have one pre-ordered :sweat_smile: I love Moog as a company, they are good people. And the Subharmonicon has to be one of the most interesting releases by a major manufacturer in a long time.

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Ha, I received the Subharmonicon yesterday. Here’s what I did so far: