investigating the russian 6S6B-V tube

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Thanks! That would seem to suggest, then, that the 6S6B-V is not the tube in the M49V, internet speculation notwithstanding

Incidentally, our studio just got a pair of M49V, and we have another pair en route.

I’ve only heard them very briefly, but can confirm they sound fantastic on piano
Nice!
It would be very interesting to have detailed photo's taken inside the definitive version of the new M49V. Finition of the definitive build, placement of the components, values of the components. Measurement of the voltages.
 
Nice!
It would be very interesting to have detailed photo's taken inside the definitive version of the new M49V. Finition of the definitive build, placement of the components, values of the components. Measurement of the voltages.
The ones at our place don't belong to me--two of my business partners each bought a pair.

I'm not sure I'd be invited to open them up, at least not in the short term while they're new, under warranty, and working (I also happen to be located on the opposite coast from my studio at the moment, which is inconvenient!)

But I'd also be interested in same.

Have you seen Klaus Heyne's teardown and analysis of a preproduction prototype?
 
Ok, I understand.

Indeed, I've seen Klaus Heyne's review of the prototype.

As you have the definitive version at hand, it would have been soooo nice to see the inside and to have measurements of voltages ( B+, anode, cathode).
So easy to open the M49... Will be very tempting for you!

Of course, decision is up to your partners!
Look forward to read further impressions about sound!

Paul
 
Thanks! That would seem to suggest, then, that the 6S6B-V is not the tube in the M49V, internet speculation notwithstanding

Incidentally, our studio just got a pair of M49V, and we have another pair en route.

I’ve only heard them very briefly, but can confirm they sound fantastic on piano
... So are you going to open them up? 😉
 
I was cautious about posting my find, simply because people might start hamstring the tube. Having in mind the Ru/Ukr situation, I don't think hamstring will be happening anytime soon.

Whether or not this tube is found in this new Neumann it's a great find, and remarkable tube. I managed to score 10 pieces. Looks exactly like 6s6b-v.

By digging through different russian tubes i "discovered" a 6s6b "upgraded" model, which is 6s26b-k. They perform exactly as 6s6b-v but with extremely low microphonics. The 6s6b-v is already low in microphonics - coeficient of 100, but 6s26b-k has coeficient of 20! Not only that, according to some rough google translations 6s6b are low in microphonics and resonances, whatever that might mean, in range 10-600hz. But 6s26b covers wider range 10-4000hz.

"It was made (in the same version, with flat "combs" through which
conclusions pass, from the bottom of the cylinder) a series of lamps of increased vibration resistance for
work in on-board equipment, which is characterized by vibrations, is often very
strong. These are 6S26B-K, 6S27B-K, 6Zh31B-K, 6K11B-K. Their parameters are exactly
match the parameters of the prototypes - 6S6B-V, 6S7B-V, 6Zh1B-V, 6K1B-V, for
except for a much lower vibration noise voltage, which is achieved by a strong
design that eliminates mechanical resonances in a wide frequency range
(10-4000 Hz, for ordinary ones - up to 600 Hz), plus a check for vibration noise in a wide
vibration frequency range with rejection of all those with an increased level

vibration noise."

https://pogorily.livejournal.com/47920.html
 
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If they sound "flatter" than the 6S6B it will be a good thing, but if the diferencie is just less noise or less microphonics I would not be so tempted to look for them.
Thank you anyway for sharing )
 
Thanks! That would seem to suggest, then, that the 6S6B-V is not the tube in the M49V, internet speculation notwithstanding

Incidentally, our studio just got a pair of M49V, and we have another pair en route.

I’ve only heard them very briefly, but can confirm they sound fantastic on piano
6S6B tubes don’t usually (ever?) have that written on them, they have the cyrillic equivalent.

V just means vacuum tube.

I can’t remember the exact phrasing, but I think Klaus commented about learning something regarding russian tube designations here. You might search.

My takeaway was that Klaus had seen the cyrillic and didn’t realize it was a 6S6B until after he had already argued against it. Just what it seemed to me, may be wrong.

There aren’t any other submini tubes with a matching structure or other electrical properties that I can find, or anyone else can seem to find.
 
I was cautious about posting my find, simply because people might start hamstring the tube. Having in mind the Ru/Ukr situation, I don't think hamstring will be happening anytime soon.

Whether or not this tube is found in this new Neumann it's a great find, and remarkable tube. I managed to score 10 pieces. Looks exactly like 6s6b-v.

By digging through different russian tubes i "discovered" a 6s6b "upgraded" model, which is 6s26b-k. They perform exactly as 6s6b-v but with extremely low microphonics. The 6s6b-v is already low in microphonics - coeficient of 100, but 6s26b-k has coeficient of 20! Not only that, according to some rough google translations 6s6b are low in microphonics and resonances, whatever that might mean, in range 10-600hz. But 6s26b covers wider range 10-4000hz.

"It was made (in the same version, with flat "combs" through which
conclusions pass, from the bottom of the cylinder) a series of lamps of increased vibration resistance for
work in on-board equipment, which is characterized by vibrations, is often very
strong. These are 6S26B-K, 6S27B-K, 6Zh31B-K, 6K11B-K. Their parameters are exactly
match the parameters of the prototypes - 6S6B-V, 6S7B-V, 6Zh1B-V, 6K1B-V, for
except for a much lower vibration noise voltage, which is achieved by a strong
design that eliminates mechanical resonances in a wide frequency range
(10-4000 Hz, for ordinary ones - up to 600 Hz), plus a check for vibration noise in a wide
vibration frequency range with rejection of all those with an increased level

vibration noise."

https://pogorily.livejournal.com/47920.html
I couldn’t find any of those that were a visual match as far as the inner structure goes. It would be cool to see some photos that confirm a match.

I think it’s probably just 6S6B (-v) obtained from New Sensor.
 
Maybe there is one of those that’s a perfect match for what’s in the M49-V but think I spot at least four physical differences (stopped counting after it seems it’s not the one, to me). The insulating spacers don’t appear correct for one.
 
Maybe there is one of those that’s a perfect match for what’s in the M49-V but think I spot at least four physical differences (stopped counting after it seems it’s not the one, to me). The insulating spacers don’t appear correct for one.
There are two variants of both 6s26b-k and 6s6b-v models that look different. I have both variants and they are identical both visually and perform the same. Not really different structure, just how the pins are connected and getter.
 
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I’m not arguing that it isn’t a 6s26b-k. I’m just saying I have yet to see one visually match the tube in the M49-V, whereas there have been 6S6B-V available that seem to be a match in all regards.
 
I know Klaus Heyne said definitively that the tube in the M49V is not a 6S6B.

Is a 6S6B-V considered a different tube type? Or is it more like “12AX7A” compared to “12AX7”?
Hello,

If you read carefully, that’s not what he actually wrote. The tube in the "prototype“ wasn’t the 6s6b. However, when it returned for final evaluation, the tube was changed, and he didn’t know what it was. So a confirmed non confirmation.

I do find it an odd coincidence that since, many of the large stockpiles have been bought up…


Anyway, having been interested, I visually compared the two in pictures, and I couldn’t see any differences. Also, the Beez Neez mics owner is convinced that’s what it is. He also uses them in his 49.

Here’s pics if anyone is interested, attributed to Klaus Heyne

3439534A-3237-4C34-87C2-8AC3B60F1B04.jpeg58396352-0220-40E4-B514-ACB14025B784.png47C8226A-6C6A-4D99-9367-3C279722679F.png58396352-0220-40E4-B514-ACB14025B784.png
 
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There are two variants of both 6s26b-k and 6s6b-v models that look different. I have both variants and they are identical both visually and perform the same. Not really different structure, just how the pins are connected and getter.
Isn’t the plate voltage of the 6s26b 250v?

http://www.russiantubes.ru/prop.php?t=12&p=313

or perhaps not?

http://klausmobile.narod.ru/td/data/_6s26bk.GIF
 
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