A test of 211 valves on youtube:
https://m.youtube.com/watch?v=CE06dli78mo
An impressive collection of 211 tubes.
https://m.youtube.com/watch?v=CE06dli78mo
An impressive collection of 211 tubes.
Last edited:
211 valves: please share your experiences
- Thread starter Audiocrack
- Start date
Here is a link in which various 211 brands/valves come along while being used in an Audio Note UK Kensei/Ongaku amp:
http://forums.stevehoffman.tv/threa...-xlr-sogun-mains-now-up-running.685663/page-4
http://forums.stevehoffman.tv/threa...-xlr-sogun-mains-now-up-running.685663/page-4
Last edited:
Here is a very interesting link in which Peter of Audio Note UK ranks his favourite (211 based) tubes in one of his own set amps (Ongaku Kensei). Note that he (also) ranks the Amperex 211 valves higher than the (regular) United Electronics 211 tubes:
https://www.audioasylum.com/cgi/t.mpl?f=set&m=74257
Btw 1:Audio Note UK does supply Elrog 211 tubes anymore with their amps.
Btw 2: Peter prefers 211 based amps to 300b based amps.
https://www.audioasylum.com/cgi/t.mpl?f=set&m=74257
Btw 1:Audio Note UK does supply Elrog 211 tubes anymore with their amps.
Btw 2: Peter prefers 211 based amps to 300b based amps.
Last edited:
Quote:
"With the success of the UV-203, the RCA Company announced a new version of the “50 watter” in 1923. The 203 was designed as a transmitting tube and there was a need for tubes that would work better as audio amplifiers. AM broadcasting was starting to catch on and modulation tubes were desirable. Audio tubes don’t require any special design above that required for a transmitting tube. The 203 had a mu or amplification factor of 25, so reducing the number of turns on the grid would reduce the mu. The UV-211 had a mu of 12.5. The KFBK (Sacramento) transmitter of 1924 had a pair of 50 watters in parallel in a Hartley circuit and was modulated by a pair of 211 types. The military designated the new tube as the VT-4-B and General Electric, who actually made the tubes, called it the PR-11-A. RCA was not shy about stealing ideas and the 211 was a good example. In 1921, the Western Electric Company developed a similar tube called the WE-211A. RCA held the triode patent, so they got away with a lot.
The UV-211 was replaced by the 211 or VT-4-C. In the 1930s, military designers were developing transmitters for the new heavy bombers. The BC-375 was made in vast numbers before and during WWII. This transmitter had three 211s in the final and one as a modulator. One BC-375 was used in every B-17, B-24, B25, B-26 and early B29s. They were also used in portable and mobile applications. The VT-4-C was very common after the war and they were everywhere along with the BC-375s. You could buy them for a dollar at any swap meet.
Then the audio nuts discovered the better sound from vacuum tubes than solid state and the rush was on. It a short time the VT-4-C cost $75 each and they are still climbing. Recent eBay sales are well over $100. New single ended audio amplifiers are being sold and big bucks using the old VT-4-C. Never give up on an old tube."
"With the success of the UV-203, the RCA Company announced a new version of the “50 watter” in 1923. The 203 was designed as a transmitting tube and there was a need for tubes that would work better as audio amplifiers. AM broadcasting was starting to catch on and modulation tubes were desirable. Audio tubes don’t require any special design above that required for a transmitting tube. The 203 had a mu or amplification factor of 25, so reducing the number of turns on the grid would reduce the mu. The UV-211 had a mu of 12.5. The KFBK (Sacramento) transmitter of 1924 had a pair of 50 watters in parallel in a Hartley circuit and was modulated by a pair of 211 types. The military designated the new tube as the VT-4-B and General Electric, who actually made the tubes, called it the PR-11-A. RCA was not shy about stealing ideas and the 211 was a good example. In 1921, the Western Electric Company developed a similar tube called the WE-211A. RCA held the triode patent, so they got away with a lot.
The UV-211 was replaced by the 211 or VT-4-C. In the 1930s, military designers were developing transmitters for the new heavy bombers. The BC-375 was made in vast numbers before and during WWII. This transmitter had three 211s in the final and one as a modulator. One BC-375 was used in every B-17, B-24, B25, B-26 and early B29s. They were also used in portable and mobile applications. The VT-4-C was very common after the war and they were everywhere along with the BC-375s. You could buy them for a dollar at any swap meet.
Then the audio nuts discovered the better sound from vacuum tubes than solid state and the rush was on. It a short time the VT-4-C cost $75 each and they are still climbing. Recent eBay sales are well over $100. New single ended audio amplifiers are being sold and big bucks using the old VT-4-C. Never give up on an old tube."
Oh, oh, oh ... we stupid audiophiles missed the opportunity to get these nos 211 valves at very attractive prices ... even in the sixties and the seventies of the last century they were pretty cheap ... but high quality nos 211 tubes have become so rare (maybe apart from the GE 211) and expensive these days that a price of well over usd 100 seems ridiculous low nowadays ... I clearly missed the nos 211 boat in the good old days and I am probably not the only stupid one out there ...
Nice quote, Justin.
Last edited:
The power of the internet - a few days ago I could find GE 211's at nice prices in a few sellers, today some show "price on application"!
Just one question: isn't there a russian equivalent triode, even with a different socket arrangement?
For the - perceived - top notch nos 211 valves such as Amperex, RCA and United Electronics the prices are already outrageous, in particular if you need (ideally) a matched quod. This apart from the fact that such a quod is very difficult to find. And that is of course reflected in these ‘stupid’ prices.
So it would really be a blessing if one of current the tube factories could come up with a 211 tube that can actually compete with the mentioned nos brands. As far as I know we are not there yet.
Thomas Mayer has taken on Elrog production. Does anyone have experience of his “new” 211s?
My 18 months of running pre-Mayer Elrog 845s in my Audion Black Shadow SET monos was a real case of “beauty and the beast”, a beautiful sound but beastly unreliability.
My 18 months of running pre-Mayer Elrog 845s in my Audion Black Shadow SET monos was a real case of “beauty and the beast”, a beautiful sound but beastly unreliability.
Can you adjust/check bias independently for each 211 in your Kagura amplifiers?
Why no longer required? There should be a market for top notch 211 valves in my view. Maybe Thomas Mayer’s ‘special version’ 211 is such a tube but the price for this valve - that has no track record at all nor any review - is outrageous as well.
Rudolph, are these the Elrog 211s that Thomas started re manufacturing 2 years ago? Are there any reports on improved reliability (things certainly couldn’t have been worse back in the day)? How exhorbitant is the pricing?
Then there is always the risk that your findings are also due to how close the tubes are matched. I went through this problem in several amplifiers. This is one reason why many manufacturers insist that customers should buy well burn-in and matched tubes from them.
When needing four matched tubes I always get five or even six - otherwise if one goes faulty it is almost impossible to get a proper replacement.
Audiophiles are a very small market. The real tubes were made for something else.
I was referring to the Elrog 242 tube, fully interchangeable with the 211 valve, that is only made on special order. A pair costs Euro 2600.
Last edited:
Yes, you are right. Therefore I understand the approach of the Kondo factory as regards not using nos tubes for their amps. However, and as mentioned before, the differences between their stock (Chinese) tubes and the nos valves that I am currently using are night and day.
And of course the 2 x 2 stock Kondo 211 valves were closely matched by the Kondo factory. Actually they deliver the various Kagura tubes with numbers that correspond with numbers on the amps; so there can be no mistake where to put them.
Notwithstanding this ‘Kondo matching’ my nos RCA 211 valves from 1942 sound superior. It is not so much a matter of a lower noisefloor or greater transparency but the former (the Kondo stock 211 tubes) sound ‘synthetic’ and ‘crude’ in comparison to the latter: the liquidity, the smoothness, the refinement and - as a consequence - the ‘musicality’ of the RCA’s are on a different level.
When you matched your tubes, did you check from time to time how they developed? And maybe now and then replaced one or more because the originally matched valves started to ‘drift apart’?
Last edited:
That is true of course but the outrageous prices that are demanded and actually paid for high quality nos 211 valves demonstrate in my view that there is a serious market for top notch 211 tubes.
Similar threads
