NuTube miniature double triode

[valveaudio]

Looks like a device which will be used to sell "valve sound"

http://www.nutube.us

Trevor

[Duke_Nukem]

Cool ! I've so got to get me one of these - not for any audio reasons, simple what an interesting looking device.

TTFN,
Jon

[G8HQP Dave]

I seem to recall an earlier thread about that. It is essentially a rework of a display device, to provide a rather puny triode for use in an effects box masquerading as an audio preamp.

I remember the earlier thread, you could do the same with a multiplexed VFD and have a few common cathode triodes. Some with two anodes some with two grids depending on how you wire it up. The anodes would glow as well!

Upon reading some of the 'literature' about the 'tube' this popped up...

The real triode structure produces a warm, unique vacuum tube sound, delivering excellent linearity.

I'll say no more.

[Radio Wrangler]

Oooh and it ticks the directly heated box as well!

Some people could get a little overheated about it. However, it needs to have a plug-in ZIF socket so they can spend hours comparing the acoustic signatures of different date codes.

I wonder what happened to those field emission devices which emitted electrons from a 2-dimensional array of cold spiky points?

David

[G8HQP Dave]

It is a good example of how capitalism doesn't just force the market to meet buyers' needs, but also persuades buyers to meet the producers' needs.

[turretslug]

Yep- there must be a fair amount of VFD manufacturing plant that isn't quite as busy as it used to be and this looks like a handy means of extending and maximising return on investment.

Every few years, a "miniature cold-cathode device" story pops up, and then things go quiet again. Either it's a non-starter (balance of probability?), or it's very significant indeed and gets sat on (in the way that the Russians noticed that nuclear research articles disappeared from American scientific journals post-1942....)

It is obvious that field effect and transistor electrons are cold, ones emitted by a hot cathode are much better.

[ms660]

The Vox MV50 series uses them, here's a demo with the Vox MV50-AC which has the Nutube in it...Luv it:

https://www.youtube.com/watch?v=DY5AlUj0i2c

Anyone fancy building a regen receiver with one?

Lawrence.

[mole42uk]

I rather liked the bit about the device being microphonic, so you should attach a piece of lead to it to damp out problems.

[ricard]

I agree with Duke_Nukem above that it looks really cool as esoteric, it doesn't look like a VFD, really, and not like anything else either.

But, honestly, is this not a bit of a gimmick? Sure it certainly provides some sort of 'vacuum tube sound' but I would think it has a sound of its own rather than accurately reproducing that good ole overdriven valve amp sound.

[G6Tanuki]

Originally Posted by ricard

Sure it certainly provides some sort of 'vacuum tube sound' but I would think it has a sound of its own rather than accurately reproducing that good ole overdriven valve amp sound.

I wonder what frequencies these go up to - could I use both halves of one of these as a push-pull RF amp? What sort of output would it produce in Class-C?? Would it need neutralising??

[IMHO if an amplifier has a detectable "sound" then it's in need of major rework to improve its linearity!]

But, honestly, is this not a bit of a gimmick?

Yes.

[ColinTheAmpMan1]

Originally Posted by ricard

But, honestly, is this not a bit of a gimmick? Sure it certainly provides some sort of 'vacuum tube sound' but I would think it has a sound of its own rather than accurately reproducing that good ole overdriven valve amp sound.

I agree that it is probably a gimmick, but I don't think the audiophools would appreciate "overdriven valve amp sound". This is the stamping-ground of guitar-players (like me). I don't mind going on record as saying that an overdriven pre-amp valve sound is that much like an overdriven output-valve sound. Of course, it depends on the circumstances - if you are considering a little 2-Watt amplifier using both halves of an ECCxx valve in class A, then I am clearly wrong, but a couple of EL34s in push-pull class AB is a different proposition. For one thing, you will never be able to get as much feedback from the 2-Watt amp as from two EL34s.

Personally, I don't think the current US-owned Vox products hold a candle to the original UK-made Jennings products, but then I am British and an owner of an AC30 - so I'm biased.

Colin.

[Studio263]

Apologies if these have been mentioned before, but this look interesting (if a bit expensive):

https://uk.rs-online.com/web/p/doubl...alves/1449016/

Reading between the lines, "gives just as much distortion as a conventional valve amplifier". Must be good then. Glows just like the real thing (but in green). As anyone knocked up a circuit to see if they work?

[factory]

The emails I get from RS have links to a Designspark project using this VFD triode, they are only building a guitar pedal with it though;

Links to the project so far;
Part 1 https://www.rs-online.com/designspar...-1-tube-basics
Part 2 https://www.rs-online.com/designspar...rt-2-prototype
Part 3 https://www.rs-online.com/designspar...&bid=539491908

David

[G8HQP Dave]

There was a thread about these a few months ago. They are essentially a 'toy' item, to keep the VFD productions lines going. Rumoured to be microphonic too.

[AC/HL]

Threads merged.

[Ed_Dinning]

Hi Gents, I think I'll market a board with one or 2 EM81/82 valves on it. That should tick all the boxes.

Ed