Tubes: Modern vs Vintage

[watchnerd]

Possibly an unpopular topic at ASR, tubes being a bit audiophool, but what the heck.

I'm buying some replacement tubes for my preamp, which uses 6SN7 tubes.

As always, I'm faced with the choice between modern production tubes from Slovakia (JJ), Russia (Tung Sol, Sovtek, Electroharmonix) and China vs vintage models at several times the cost.

My various components use 6DJ8, 12AX7, and 6SN7 tubes. So far, I've yet to find a vintage tube that is objectively better than the modern production. Different, yes. But better...?

What are your thoughts / experiences on modern tubes vs vintage / NOS?

 

[tomelex]

Possibly an unpopular topic at ASR, tubes being a bit audiophool, but what the heck.

I'm buying some replacement tubes for my preamp, which uses 6SN7 tubes.

As always, I'm faced with the choice between modern production tubes from Slovakia (JJ), Russia (Tung Sol, Sovtek, Electroharmonix) and China vs vintage models at several times the cost.

My various components use 6DJ8, 12AX7, and 6SN7 tubes. So far, I've yet to find a vintage tube that is objectively better than the modern production. Different, yes. But better...?

What are your thoughts / experiences on modern tubes vs vintage / NOS?

In the day when I looked at this stuff, I found variations in standard tube parameters of 10% and more, say for example between 12at7 from the same manufacture and even more when comparing across different manufactures of the 12at7. Variations can he even higher, of course. So, the only thing I can say is that you need to match them as close as possible to each other, then that's the best you can do, that's what I did in the tube preamp I had at one time, play same signal into each channel, load each channel with whatever load your power amp was, and do a subtraction on the scope, swap tubes till its as low as you can get, then that's as good as you can get. No two tubes are the same, however, in feedback circuits that differences are pretty much obliterated. I match my power amp tubes because I want the best imaging I can get and that means same amplification for each channel and hence better imaging.

NOS or new, same issue.

 

[watchnerd]

In the day when I looked at this stuff, I found variations in standard tube parameters of 10% and more, say for example between 12at7 from the same manufacture and even more when comparing across different manufactures of the 12at7. Variations can he even higher, of course. So, the only thing I can say is that you need to match them as close as possible to each other, then that's the best you can do, that's what I did in the tube preamp I had at one time, play same signal into each channel, load each channel with whatever load your power amp was, and do a subtraction on the scope, swap tubes till its as low as you can get, then that's as good as you can get. No two tubes are the same, however, in feedback circuits that differences are pretty much obliterated. I match my power amp tubes because I want the best imaging I can get and that means same amplification for each channel and hence better imaging.

NOS or new, same issue.

Well that's waaaay too objective to explain all the worship that some have for vintage tubes.

 

[tomelex]

I know,

Try this subjective remark: the more it costs, the harder it is to find, the less available for others due to cost or scarcity, in other words, the more I can single myself out, then what I have has to be better than all the rest of you dudes and dudets possess. I don't need no stinkin blind tests to tell me what I already know..... hahahahhahh

 

[watchnerd]

I know,

Try this subjective remark: the more it costs, the harder it is to find, the less available for others due to cost or scarcity, in other words, the more I can single myself out, then what I have has to be better than all the rest of you dudes and dudets possess. I don't need no stinkin blind tests to tell me what I already know..... hahahahhahh

I suppose you're not keen on cryo-treatments, either.

 

[tomelex]

That's another area where the science is true, but the audibility is never been proven by proper blind tests IIRC.

 

[Blumlein 88]

Back when I did the tube thing, yeah match the tubes. Some modern production is actually better. Some is not. Matching is about what you can do to help. Don't know, but at one time you could scare up JAN (Joint Army Navy) milspec tubes. These weren't always the best sounding, but they were closely spec'd, reliable and had long lives. They also had alternate numbers like 5965 for the JAN 12at7. Used those in the input and driver stages of my old VTL amps. You can go rally crazy and look for certain plate configurations. Best 12at7 in my opinion/experience are the old Telefunken's. But I haven't purchased tubes in a decade so I am not up to date.

 

[Sal1950]

Back when I did the tube thing, yeah match the tubes. Some modern production is actually better. Some is not. Matching is about what you can do to help. Don't know, but at one time you could scare up JAN (Joint Army Navy) milspec tubes. These weren't always the best sounding, but they were closely spec'd, reliable and had long lives. They also had alternate numbers like 5965 for the JAN 12at7. Used those in the input and driver stages of my old VTL amps. You can go rally crazy and look for certain plate configurations. Best 12at7 in my opinion/experience are the old Telefunken's. But I haven't purchased tubes in a decade so I am not up to date.

I had the same style VTL amps and tried matching 12AT7 tubes by the Gm on my conductance tester. Even with a whole slew of both new and old OEM tubes, in the end I was trying to pull out the hair I didn't have. My main problems always fell back to tube noise and even the quietest never remained so for very long. Systems overall gain was very high and any low level tube noise was very obvious.
Sovtek Russian output tubes proved to be extremely stable and reliable over time. Never had a failure over a 20 year span with those monoblocks, only replacing a set out of preventive maintenance. I would tweek the bias on all 8 every few months or so but they never required more than a tiny tweek. Very good tubes IME.

 

[Blumlein 88]

I had the same style VTL amps and tried matching 12AT7 tubes by the Gm on my conductance tester. Even with a whole slew of both new and old OEM tubes, in the end I was trying to pull out the hair I didn't have. My main problems always fell back to tube noise and even the quietest never remained so for very long. Systems overall gain was very high and any low level tube noise was very obvious.
Sovtek Russian output tubes proved to be extremely stable and reliable over time. Never had a failure over a 20 year span with those monoblocks, only replacing a set out of preventive maintenance. I would tweek the bias on all 8 every few months or so but they never required more than a tiny tweek. Very good tubes IME.

I never had the slightest problem with noise on VTLs. Had experience with 4 sets of their amps. In fact they were the quietest tubes units I've ever used. Much stiffer power supplies than the norm for tube units.

 

[Sal1950]

I never had the slightest problem with noise on VTLs. Had experience with 4 sets of their amps. In fact they were the quietest tubes units I've ever used. Much stiffer power supplies than the norm for tube units.

No doubt the result of having them paired with 105db sensitive La Scalas. I also had to use extra measures in other areas to avoid any grounding/hum issues.

 

[watchnerd]

I ordered a quad of "matched" new production Tung Sol 6NS7. We'll see how it goes.

 

[hvbias]

What are your thoughts / experiences on modern tubes vs vintage / NOS?

I go for whats reliable and doesn't break the bank. Not too scientific That said I am a fan of direct heated triodes so that mostly leaves me in the vintage category.

I don't really believe in "brand sound" I think those sort of things get propagated and listener bias sets in and people hear what they've read. I think it has more to do with variations in manufacture, tolerance and in some circuits matching. That is not to say I'm discounting brand meaning entirely. Someone once measured all their 45s on a digital tube circuit and found one make in particular was so different from the rest that it might as well have been a different tube model. The Rp of a tube that likes a specific load vs one that has a different Rp with the same load, it shouldn't be too surprising that these two will sound different. A bit on matching, if these are run in a push pull circuit two tubes that are more closely matched will have more even harmonic cancellation.

 

[Blumlein 88]

No doubt the result of having them paired with 105db sensitive La Scalas. I also had to use extra measures in other areas to avoid any grounding/hum issues.

Well that would explain. A friend with some K-horns uses a low power Class D amp. Now that is match made in heaven. Quiet as can be.

 

[tomelex]

I go for whats reliable and doesn't break the bank. Not too scientific That said I am a fan of direct heated triodes so that mostly leaves me in the vintage category.

I don't really believe in "brand sound" I think those sort of things get propagated and listener bias sets in and people hear what they've read. I think it has more to do with variations in manufacture, tolerance and in some circuits matching. That is not to say I'm discounting brand meaning entirely. Someone once measured all their 45s on a digital tube circuit and found one make in particular was so different from the rest that it might as well have been a different tube model. The Rp of a tube that likes a specific load vs one that has a different Rp with the same load, it shouldn't be too surprising that these two will sound different. A bit on matching, if these are run in a push pull circuit two tubes that are more closely matched will have more even harmonic cancellation.

Yeah, but there are several makers of new DHT tubes as you know, so in a way you are with the times.

 

[watchnerd]

Yeah, but there are several makers of new DHT tubes as you know, so in a way you are with the times.

DHT?

 

[Blumlein 88]

DHT?

Directly Heated Triode

Most tubes have a separate heater element that makes them glow. Hence the 6 or 12 volt designation. However DHT has DC flowing through the cathode itself. It also often gives them better linearity than indirectly heated tubes. Notice below this illustration shows indirect heating element.

at the other end of tube evolution are the Nuvistors. These babies had nice performance, were very small, and would last a long, long time.

 

[watchnerd]

Directly Heated Triode

Most tubes have a separate heater element that makes them glow. Hence the 6 or 12 volt designation. However DHT has DC flowing through the cathode itself. It also often gives them better linearity than indirectly heated tubes. Notice below this illustration shows indirect heating element.

Huh...none of my tubes look like that, at least not that I can tell:

I guess that's a good thing?

 

[Blumlein 88]

Huh...none of my tubes look like that, at least not that I can tell:

I guess that's a good thing?

Depends upon whom you ask. Yes, yours are all indirectly heated tubes. The one pictured is typical.

Hey you could one day have something like these unusual Amberwave amps. DHT triodes, but in push pull with near 200 watts of clean power. Usually DHTs are used as SETs.

Here is the datasheet on the transmitter tube adapted for audio use here.
https://frank.pocnet.net/sheets/140/3/304TL.pdf

 

[Deleted member 65]

Got the tubes below today to be installed in my new DAC scheduled to arrive mid February. Promised myself & spouse no more tubes to avoid intervention from ASR ... ;-

Svetlana Winged C / 5U4G/5U3C-SVETLANA WINGED C

MATCHED 6N23P 6Н23П VOSKHOD Single Wire TUBE QUAD 6DJ8 E88CC

To be installed in this ...

Also ordered new caps, let's leave those for another thread ...

 

[Sal1950]

To be installed in this ...

Don't look like you'll can get the lid back on now.
That's OK, I always preferred open architecture.