Anyone interested in true matching of plate characteristic of highly sought after tubes like:
Western electric 300B, 349A, 417A... etc
C3M, C3g, EC8020... etc
Anyone would like to exchange their plate characteristic curve here, if better match found, we can negotiate to exchange tube here for the best matching accuracy.
Those do not have curve tracer can manual plot it with variable voltage power supply and oscilloscope or multimeter.
Once we know each other, we can exchange curve of tubes we have got and put it in the database of this forum
Best matching accuracy is then possible with accumulation of large number of tubes of similar characteristic.
Western electric 300B, 349A, 417A... etc
C3M, C3g, EC8020... etc
Anyone would like to exchange their plate characteristic curve here, if better match found, we can negotiate to exchange tube here for the best matching accuracy.
Those do not have curve tracer can manual plot it with variable voltage power supply and oscilloscope or multimeter.
Once we know each other, we can exchange curve of tubes we have got and put it in the database of this forum
Best matching accuracy is then possible with accumulation of large number of tubes of similar characteristic.
Hmm...
I dunno--Seems a risky idea, sending very expensive tubes--prob overseas-- to unknown destinations with only goodwill for security.
I know to my recent cost sending a vintage tube overseas has left me seriously out of pocket due to the buyer damaging it by incorrect tube-tester use, such is the hobby of audiophoolery.
Audiophools--They THINK they know what they are doing, they go buy themselves a Tube Tester and then don't have a clue how to use it, they buy a known good tube they then kill, so the seller has to eat the costs.....
Sorry, but I don't think your idea will fly.
I dunno--Seems a risky idea, sending very expensive tubes--prob overseas-- to unknown destinations with only goodwill for security.
I know to my recent cost sending a vintage tube overseas has left me seriously out of pocket due to the buyer damaging it by incorrect tube-tester use, such is the hobby of audiophoolery.
Audiophools--They THINK they know what they are doing, they go buy themselves a Tube Tester and then don't have a clue how to use it, they buy a known good tube they then kill, so the seller has to eat the costs.....
Sorry, but I don't think your idea will fly.
I am sorry for your loss. But, more importantly, we have to look for more solution than problem. I believe solution is more available than problem. I believe those able to submit the plate characteristic curve know enough to use the tube properly. You can also at-test him until you are confident enough to exchange any idea or tube.
In a perfect world--Its a lovely idea, sadly we all know the world is far from perfect.
There's a more fundamental problem and that is that most of the membership here are not collecting large (or any) quantities of the sort of tubes well healed audiophiles tend to be interested in.
I'm relatively affluent and yet I don't own a single WE 300B, and never have. I do own a small number of C3G and gifted all of my C3M to a friend. (And I have JJ and Svetlana 300B) I had the opportunity to purchase a well used pair of WE 300B and concluded that the incremental improvement over the JJs was not worth the expenditure in the system as it existed at that time.
I use lots of inexpensive Russian military surplus or devices made by EML and Halske-Siemens.
I'm relatively affluent and yet I don't own a single WE 300B, and never have. I do own a small number of C3G and gifted all of my C3M to a friend. (And I have JJ and Svetlana 300B) I had the opportunity to purchase a well used pair of WE 300B and concluded that the incremental improvement over the JJs was not worth the expenditure in the system as it existed at that time.
I use lots of inexpensive Russian military surplus or devices made by EML and Halske-Siemens.
It isn't terribly difficult to design amplifiers that can accommodate mismatch. That has been my strategy. Even with "matched" tubes there is some degree of mismatch and with an AC balance pot and individual bias settings, you can achieve much better balance than relying on matching of tubes themselves.
Also, Tubes may match today--but not tomorrow. They all age differently and even just slight differences in heater volts for instance can seriously affect an apparent match.
Tubes tested on different testers by different people showing an apparent match are sure to end up being different when tested on same tester by just one person using the exact same parameters.....
Better to design the amp to account for an adjustable matching to periodically tune in to get exact match in the amp they are used in.
Personally--I see little point in matching on testers, Better to design a good amp with variable/settable parameters.
Tubes tested on different testers by different people showing an apparent match are sure to end up being different when tested on same tester by just one person using the exact same parameters.....
Better to design the amp to account for an adjustable matching to periodically tune in to get exact match in the amp they are used in.
Personally--I see little point in matching on testers, Better to design a good amp with variable/settable parameters.
Raj,
I have thousands of tubes in my parts bins, and it was unlikely I was ever going to put the C3M to use so I gave them to someone who hopefully will.
I do have BA, C3G and Philips 18040 that I am saving for future projects.
I generally prefer DHTs in moderate mu applications and use EML 20AM (mu of 20 and rp 4.7K) in my line stage.
Higher gain stuff I tend to go for things like the D3A, E810F, 417A/5842 or 6S3P-EV. I sometimes use ECC88/E88CC but have found I prefer Amperex BB, Teles, and Mullard, but I am very unwilling to pay extortionate prices for them. (I grab them when I can and was given some a few years back.)
I have thousands of tubes in my parts bins, and it was unlikely I was ever going to put the C3M to use so I gave them to someone who hopefully will.
I do have BA, C3G and Philips 18040 that I am saving for future projects.
I generally prefer DHTs in moderate mu applications and use EML 20AM (mu of 20 and rp 4.7K) in my line stage.
Higher gain stuff I tend to go for things like the D3A, E810F, 417A/5842 or 6S3P-EV. I sometimes use ECC88/E88CC but have found I prefer Amperex BB, Teles, and Mullard, but I am very unwilling to pay extortionate prices for them. (I grab them when I can and was given some a few years back.)
Great match pair in good circuit is everything
Well, many single ended single or double stage circuit require matched pair. In feedback circuit or follower application it does not make much difference. However, those circuit usually cannot satisfy high ended audiophile.
Tube rolling with no idea in its sound at what operating is misleading or time consuming because it is abitrary or based on biased opinion.
Well, many single ended single or double stage circuit require matched pair. In feedback circuit or follower application it does not make much difference. However, those circuit usually cannot satisfy high ended audiophile.
Tube rolling with no idea in its sound at what operating is misleading or time consuming because it is abitrary or based on biased opinion.
Hi Kevin,
C3M is extremely linear tube, even as triode. I love it, this is one of my favourite indirect heater tube.
I have a few dozens of used C3M tubes, at 240Vpp output signal the distortion is typically 0.5% (0.33-0.86%).
At 10-30mA anode current region Ri about 2k-2k5, mu is 17-18, and self noise is very low.
C3g is easier to use (6.3V heater is more handy than 20V), -I use this tubes from phono to VAS stage in amplifiers- but C3M mesh plate is unique in this price range, and the tone is inimitable.
I think, a pity to miss to try this tube.
p.s. : I'm in the 10/10Y/VT25...801/VT62 "business"
Matching these 80-90 year old tubes is painfully. :-(
C3M is extremely linear tube, even as triode. I love it, this is one of my favourite indirect heater tube.
I have a few dozens of used C3M tubes, at 240Vpp output signal the distortion is typically 0.5% (0.33-0.86%).
At 10-30mA anode current region Ri about 2k-2k5, mu is 17-18, and self noise is very low.
C3g is easier to use (6.3V heater is more handy than 20V), -I use this tubes from phono to VAS stage in amplifiers- but C3M mesh plate is unique in this price range, and the tone is inimitable.
I think, a pity to miss to try this tube.
p.s. : I'm in the 10/10Y/VT25...801/VT62 "business"
Matching these 80-90 year old tubes is painfully. :-(
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