Matched valves? How important?

[HighFidelityGuy]

I'm fairly new to the world of valves, so I need a bit of advice on the whole area of buying valves but particularly in the area of matching. My KEL84 requires 4x EL84 and 2x ECF80 valves. So I'm guessing that a matched quad of EL84's and a matched pair of ECF80's would give the best results but how important is it to use matched pairs/quads? Also, if I don't use a matched quad, how should I arrange two matched pairs of EL84's?

Thanks.

[Stratmangler]

This thread might well be of some use http://www.world-designs.co.uk/forum...ighlight=kel84

[lurcher]

To sum it up, two matched pairs of el84s, one per side. no point or even any real chance of matching the ecf. No point in using a matched quad.

[HighFidelityGuy]

Ok thanks, that simplifies things a bit.

What are your opinions on cryo treated valves?

[lurcher]

What are your opinions on cryo treated valves?

I don't have one that stands up to any objective analysis. A year or so ago I got a cryo company to agree to treat a batch of valves for a trade price, and I was going to send them round blind (with untreated ones in there) to folk and try and collate their findings. I never got round to it as I didnt have the spare cash to buy the valves to create a sample set.

I have some feelings about why it could improve things. It seems odd to me that in general older components seem to be better regarded. Of course it could just be selection bias doing that, but assuming there was some real difference, the thing to consider was why. Now clearly they had got very good making valves in the 50's, but not in the 20's, and even though they had got good at the process in the 50's the goals were not the sound we seek, it was reliability and consistency. So this makes me think that the reason we like old valves so much is because they are old, i.e. made a long time ago. And I wonder if the time since making has allowed the stresses of manufacture to be releaved. And I wonder if its the same thing that cryo treating achieves. It certainly seems to have uses in industries where it would not just be used because its the "new thing".

[HighFidelityGuy]

I don't have one that stands up to any objective analysis. A year or so ago I got a cryo company to agree to treat a batch of valves for a trade price, and I was going to send them round blind (with untreated ones in there) to folk and try and collate their findings. I never got round to it as I didnt have the spare cash to buy the valves to create a sample set.

I have some feelings about why it could improve things. It seems odd to me that in general older components seem to be better regarded. Of course it could just be selection bias doing that, but assuming there was some real difference, the thing to consider was why. Now clearly they had got very good making valves in the 50's, but not in the 20's, and even though they had got good at the process in the 50's the goals were not the sound we seek, it was reliability and consistency. So this makes me think that the reason we like old valves so much is because they are old, i.e. made a long time ago. And I wonder if the time since making has allowed the stresses of manufacture to be releaved. And I wonder if its the same thing that cryo treating achieves. It certainly seems to have uses in industries where it would not just be used because its the "new thing".

It is an interesting subject. I think think there will be a combination of factors that contribute towards valves from some of the older valves sounding better than current production. Like you say, in the 50's companies like Mullard had perfected the art of making valves and had found the best materials and manufacturing processes. A lot of the knowledge from then has been lost and modern companies are having the figure it all out again the hard way. Also, back in the 50's you could put pretty much whatever chemicals or metals you liked into products. Nowadays the restrictions on toxic materials don't allow that. So perhaps some of the magic ingredients simply don't exist in current production valves. From what I've read, modern valves are getting better all the time as the manufacturers improve their techniques. So while they may never be able to fully recreate the qualities of vintage valves, hopefully they'll get very close.

As for cryo treating, I've heard a bunch of stuff about all the areas it's supposed to improve but a lot of this seems to be tailored toward guitar players. Stuff like greater harmonic content etc which worries me from a hi-fi point of view. But I have heard that cryo valves have better dynamic range, lower noise floor, lower microphonics and more detail etc. So I don't know what to think really. I guess it's a case of "you don't know until you try", which is why I was hoping someone here had some experience. I haven't seen cryo valves mentioned much on hi-fi forums though, so perhaps it's something that hasn't caught on much in the hi-fi world yet.

[lurcher]

It is an interesting subject. I think think there will be a combination of factors that contribute towards valves from some of the older valves sounding better than current production. Like you say, in the 50's companies like Mullard had perfected the art of making valves and had found the best materials and manufacturing processes. A lot of the knowledge from then has been lost and modern companies are having the figure it all out again the hard way. Also, back in the 50's you could put pretty much whatever chemicals or metals you liked into products. Nowadays the restrictions on toxic materials don't allow that. So perhaps some of the magic ingredients simply don't exist in current production valves. From what I've read, modern valves are getting better all the time as the manufacturers improve their techniques. So while they may never be able to fully recreate the qualities of vintage valves, hopefully they'll get very close.

Yes, but as I say, every time that is said, it misses the reality that the improvements that the likes of Mullard were aiming for were not the qualities that we value for audio use, and it seems a huge coincidence that what they were aiming for (consistency, less failures) should lead to the audio difference we hear in those valves. It also doesn't explain a globe 245 from 1930 sounding so great. Better in fact I would say than just about anything produced in Blackburn.

[lurcher]

I haven't seen cryo valves mentioned much on hi-fi forums though

Maybe you are not looking where I look, but cryo "just about anything" seems to be available for hifi use, including valves.

[HighFidelityGuy]

Yes, but as I say, every time that is said, it misses the reality that the improvements that the likes of Mullard were aiming for were not the qualities that we value for audio use, and it seems a huge coincidence that what they were aiming for (consistency, less failures) should lead to the audio difference we hear in those valves. It also doesn't explain a globe 245 from 1930 sounding so great. Better in fact I would say than just about anything produced in Blackburn.

I see what you're saying. I think it's just one of those things that can't be explained fully. I've usually found that when something is over-engineered it tends to work better, not just for longer. Also I've often heard people say that military spec valves sound better than standard models as they suffer less from microphony etc. I guess that some of the things that make a valve more rugged also make it sound better. Tighter manufacturer and testing tolerances will also have something to do with this.

Maybe you are not looking where I look, but cryo "just about anything" seems to be available for hifi use, including valves.

I said that I hadn't seen people talking much about cryo treated stuff, not that I hadn't seen it for sale.

[lurcher]

I see what you're saying. I think it's just one of those things that can't be explained fully. I've usually found that when something is over-engineered it tends to work better, not just for longer. Also I've often heard people say that military spec valves sound better than standard models as they suffer less from microphony etc. I guess that some of the things that make a valve more rugged also make it sound better. Tighter manufacturer and testing tolerances will also have something to do with this.

Yes, but Mullard were not "over enginearing" the valves, they were trying to do what any production process does, optimise yield, reduce waste and improve consistancy. Making valves for mil use may be different as the increase acceleration and temperature requirtements would clearly help matters, but only at the expense of production cost, so Phillips would have only done what they saw as benificial to their profits in producing standard valves. I don't see that directly improving what we want from them. And it doesn't address the 1930's valve being so good.