Are some amps designed for rubbish valves

[tomjackson]

I hear that some amp builders actually design there amps to run best on average or below avgerage russian / Chinese valves as these will be the most likely replacements and are the most available.

true?

Would nice NOS valves sound better if this was the case?

[hamfist]

I have heard this too. I think it's mostly relevant to higher gain, multi gain stage amps.

  Personally, I have amps with 2, 3 and 4 gain stages, and they ALL sounds better with good (and I stress they need to be good, not just any old cr@p) vintage tubes.

[martinw]

I'm not sure how you'd design an amp for poor valves.

The biggest problem with cheaper valves is inconsistency, so that would be impossible to account for.

I have heard it said that such-and-such an amp needs NOS valves to sound good. If that's true (and let's face it, it probably isn't!  :) ) then it probably isn't a well-designed amp in the first place.

EDIT: for the record, most Russian, and some Chinese valves can actually be very good.

[JustBecos]

Not sure about designing amps to use rubbish valves.

I do know that some amp companies choose the valves not on how good they sound, but to get  the most reliable and then voice the amp to suit those valves, I suppose that could amount to the same thing

[HTH AMPS]

all preamp valves have consistent tonal traits imo - if you're knocking out thousands of amps, you want the amps to sound 'as intended' each time.  Chinese preamp valves tend to be very gainy, therefore if it's a high-gain design, you'll want to tame down the top-end fizzies using Chinese 12AX7s.  Russian preamp valves tend to be less gainy, therefore they would sound different than the Chinese ones (maybe slightly dull if lots of top end has been 'tuned' out the amp to conpensate for Chinese 12AX7s which have more gain/fizz). 

as it happens, I've got a JCM800 here at the minute with those mid-80s Chinese ECC83Ms and the amp sounds great with no fizz at all.

[Dreichlift]

As I understand it, in the old days valves could be used with higher tolerances due to the fact that they were supposedly manufactured to higher standards, especially in the UK 

Nowadays they are made to follow similar standards but perhaps not as accurately and as a result tend to not be quite as robust as the old valves. Also not all brands are alike and you generally get what you pay for.

As for NOS valves, if you had to have an artificial heart would you want a new one that had a 1 in 1000 chance of going wrong, or would you prefer one 5 times the price that at the time of manufacture had a 1 in 2000 chance of failiure but has been kicking around in someone's drawer for 30 years, dropped and had beer spilt on it?

[hamfist]

As for NOS valves, if you had to have an artificial heart would you want a new one that had a 1 in 1000 chance of going wrong, or would you prefer one 5 times the price that at the time of manufacture had a 1 in 2000 chance of failiure but has been kicking around in someone's drawer for 30 years, dropped and had beer spilt on it?

Not quite sure of your point here.

[Tellboy]

Most of the Cornfords range were voiced for Sovtek valves. When I got my Hurricane I did a bit of a Twinfan "quest for tone" and tried several different EL84s - in fact I changed so many valves that one of the pins broke off and stuck in the valve base. To be honest I did not notice a great deal of difference in the sound and ended up with Sovteks as (contrary to what some people have found) they have been consistant and reliable.

The Hellcat Combo I got about 18 months ago had the original quad set of Sovtek EL84s which apparently had been in there about 2-3 years. I spoke to Martin Kidd who said if they sounded OK he would not bother replacing them. Although they did sound great I wasn't too keen on relying on the amp with a set of valves that old and got a balanced set of Sovteks from Hotrox and these are still going strong.

Have tried several preamp valves and settled on Tung-sol ECC83s in V1 for both amps.

[Dreichlift]

As for NOS valves, if you had to have an artificial heart would you want a new one that had a 1 in 1000 chance of going wrong, or would you prefer one 5 times the price that at the time of manufacture had a 1 in 2000 chance of failiure but has been kicking around in someone's drawer for 30 years, dropped and had beer spilt on it?

Not quite sure of your point here.

Valves are the heart of your amp, while NOS valves were (in their original pristine state) more reliable than new valves, 30+ years of being rattled around in boxes, drawers and whatever will have taken its toll on the reliability of the valve. For the sake of reliability it's wiser on the whole to buy new as you really don't know how the NOS valves have been looked after.

Tone wise older is better IMHO but I'd still buy new because of reliability.

[hamfist]

As for NOS valves, if you had to have an artificial heart would you want a new one that had a 1 in 1000 chance of going wrong, or would you prefer one 5 times the price that at the time of manufacture had a 1 in 2000 chance of failiure but has been kicking around in someone's drawer for 30 years, dropped and had beer spilt on it?

Not quite sure of your point here.

Valves are the heart of your amp, while NOS valves were (in their original pristine state) more reliable than new valves, 30+ years of being rattled around in boxes, drawers and whatever will have taken its toll on the reliability of the valve. For the sake of reliability it's wiser on the whole to buy new as you really don't know how the NOS valves have been looked after.

Tone wise older is better IMHO but I'd still buy new because of reliability.

To be honest, I completely disagree. Unless they are banged around or abused in some away, valves stay pretty much inert (certainly for several decades). The internals are in an (almost) vacuum and therefore there is no oxidation or change to the metals inside.
  I have used somewhere in the region of 80-120 vintage valves, and never had a failure. In probably half as many new valves I've had two complete failures, so the stats for me certainly backs up buying old valves.
  With those who actually use good quality vintage valves, the general concensus backs up my experience. The key is to get the valves from a reliable source, or to actually know a bit about it when shopping for valves on places like ebay.

Often folks, wanting to experiment, buy a couple of dodgy "almost dead" NOS tubes off ebay, and then slate all NOS/vintage valves just because they bought a couple of dogs.

The real world experience of vintage valves is that they sit unmoved for many decades, not "rattling around". And yes, rattling around for a few years is quite likely to destroy any valve.
The key problem with modern guitarists trying to use vintage valves is that they can be very expensive from good dealers, or it can be very risky in buying from ebay unless you know what to look for.
  if you educate yourself a bit then you can pick up almost new old valves for the same (or cheaper) prices as new valves. I'd take a good old valve any day of the week, both for tone and reliability.

[ToneMonkey]

If something can hold on to a vacuum (or near vacuum) for 30 odd years, then it has my vote as being well built.

[martinw]

I'd take a good old valve any day of the week, both for tone and reliability.

You can take some of mine. I'll swap you for some new JJs.

[tomjackson]

Well I currently have a Sovtek 12AX7WA in posotion V1, the reason I have asked the question was that some cheaper amps are designed to run best on this kind of valve so I was thinking something better may not actually sound as good.

So what would be a better NOS valve and what would be a better new valve or are these fine?

what about JAN 5751, how would that sound, iv'e heard they are interchangable with 12ax7's ?

[Davey]

amps are designed to work with a specific tube type. this means the current and voltage specs of the valve were taken into consideration, when choosing the amp internals, so they work well with one another.

an amp could have been designed to work with a higher tolerance value of a valve, so it sounds good with a wider range of valves, thus eliminating some of the shortcomings of a cheap valve. however, even those amps WILL sound better with higher grade valves, as they will be more consistent and actually hit the nominal current rating of the amp, making it sound better.

what is more important is, that you chose valves that work together (matched sets and so forth) and not just throw any into the amp, just cos they are expencive

[hamfist]

I'd take a good old valve any day of the week, both for tone and reliability.

You can take some of mine. I'll swap you for some new JJs.

The thing is Martin, that I'm convinced that you must have some old, knackered vintage valves. I can think of no other explanation as to how you seem to prefer new valves.

I have tried so many valves in so many amps, and they ALL sound better with decent old Mullards/Brimars/RFTs/Mazdas in them.
 I so wish we lived nearer to each other. I'd love to have a big amp/valve tonefest with you and TF !!