NOS tube preamp/power

[user 7737]

general question...

even if i stil didn't try, i can understand NOS tubes are better in thr preamp... (i'll try ! one day, and if i can find a place where i can buy those hand to hand)

but what about the power section ? the power tubes are more expensive, so the NOS are even more expensive... do you think it worth the difference ?

in fact i can't figure it out how the power tubes are so important about the tone ! :?

 

[stokes]

You really cant say"i can understand NOS tubes are better in thr preamp" until you actually try them.Whether or not they are "better"is subjective,they sound better to me,but they may not to you.I have spent many years experimenting with NOS tubes and have acquired many over the years.I have a large collection and have discarded just as many as I have kept.The only claim I could make for certain is that a "good" NOS tube will outlast the current production tubes.Note that I said a "good NOS tube".I have had many tubes that sounded great,but only lasted a couple of hours,obviously they werent "good".With NOS tubes there is a certain amount of a gamble you take.You have no idea how the tube was stored for one,if it was sitting in a cold,damp basement for twenty odd years or mishandled and tossed about carelessly it most likely wouldnt be as good as one that was cared for properly.In fact,it is very hard to tell if a tube was actually never used,I can make an educated guess by the tubes appearance,but there is no guarantee.Even testing on my tube tester is no guarantee.I have seen an article that showed a tube that was obviously broken,the glass was cracked and it was put in a tester and the test result came out that the tube was good.In spite of the pitfalls I have mentioned,I still prefer NOS tubes and use them exclusively in all my own amps,and would argue that they are better than current production tubes.But to generally tell you that they will do it for you would not be 100% correct,you have to try it and see for yourself.As to how the power tubes are important to your tone,I can tell you that every component in the amp affects the tone to some degree,some more apparent than others and the power tubes have a very profound effect,in more ways than one.The actual brand itself,RCA,GE etc will have different degrees of effect.How the tube is biased will vary the tonal effect.These parameters will differ from amp to amp as well.There really arent any cold, hard results with any particular tube.What I hear wont necessarilly be what you hear,you really have to try it and see.Hope this helps.

 

[212Mavguy]

One thing worth remembering about new production versus NOS power tubes, in some tube types such as 6l6 you have to be careful about max voltage ratings for each tube type. Early 6l6 types such as 6l6g, 6l6ga, 6l6gay, 5881, 6l6gb, 6l6wgb are rated for less plate voltage than current production 6l6gc tubes. If your amp calls for 6l6gc it is not a good idea to run the early versions of 6l6, the plate voltage might be too high for the earlier tubes. Biasing is critical, if too much idle current is going to the plates as well as too much voltage the power tubes will die an early death and possibly take out some amp parts when they go. I'm lucky to own a couple non mesa amps taking 6l6 that have a low enough plate voltage to experiment with earlier versions of 6l6, and they are glorious sounding, superior to their 6l6gc cousins. Most if not all mesa amps taking 6l6 need the later 6l6gc rated tubes. Perhaps in some models after modding to have adjustable bias the earlier tubes might work on a case by case basis, but if the plate voltage is much over 360 volts, not a good idea.

As far as 12__7 preamp tubes it's no problem.

I have had good luck most but not all of the time on ebay for my vintage tube purchases. You can get nice tubes from dealers but plan on paying considerably more. I have found it to be worth the time and money to roll the ebay dice, have a nice variety of vintage pre and power tubes and an idea of how the various types and manufacturors of those types tend to sound, it's a good thing. Hope this helps, best of luck to you!

 

[stokes]

Yeah,I should have made that point clear.When I refer to 6L6 on this board I do mean 6L6GC.I dont think it is a good idea to put any of the lower voltage/wattage 6L6 varieties in any Boogie,dont know of any that have less than 400 plate volts,unless maybe the Subway series,but even that is too close to 400v for those tubes.I did experiment with a pair of Tung-Sol 5881's in my IIC+ just to see how fast they would die,they did surprise me,but die they did.Maybe about 12-15 hours.Ebay is a good place to find some good NOS tubes,but if you buy enough,you will get some less than ideal tubes,just par for the course when dealing with ebay.I did get a lot of good buys there.Another place I have found a lot of good tubes are at ham fests/electronic flea markets,got a lot of killer deals at some of those.Gonna have to start traveling a little further from home,all the ham fests in this area are drying up.Pretty sure I bought most of them myself.100% with you on using the earlier 6L6 and 5881's in the non-Mesa amps,they are much warmer,with incredibly smoother break-up than the 6L6GC's in the Fender/Ampeg amps.

 

[user 7737]

well... i can say "i understand"... it doesn't mean "i know"... anyone here says "NOS tubes are better", even if i didn't experiment it, i can understand people says they're better 'caus they're well made etc.. etc...

anyway...

the point was when i see the specs of my amp and the specs of NOS power tubes, the new production seem to "fit" better than the NOS ones... that's what 212Mavguy seem to confirm...

i think i'll concentrate on new production for the power section and experiment the NOS production on the preamp section... don't want to mess up with my amp... i like it too much !

 

[Rocky]

I have a Nomad and have experimented with stock Mesa tubes, NOS stuff and JJ tubes.

It sounds best with all stock tubes except for V1 where a new Tung Sol is really nice.

NOS is NOT always the way to go. Let your ears guide you.

 

[stokes]

well... i can say "i understand"... it doesn't mean "i know"... anyone here says "NOS tubes are better", even if i didn't experiment it, i can understand people says they're better 'caus they're well made etc.. etc...

anyway...

the point was when i see the specs of my amp and the specs of NOS power tubes, the new production seem to "fit" better than the NOS ones... that's what 212Mavguy seem to confirm...

i think i'll concentrate on new production for the power section and experiment the NOS production on the preamp section... don't want to mess up with my amp... i like it too much !

meursalt,I didnt mean you cant understand.....in any kind of derogatory way,I was merely stressing the fact that it is all subjective,as Rocky points out that he prefers the stock Mesa tubes,so for him NOS isnt better.It is likely to vary from one user to the next.
As for the tube "specs",new production and NOS have the same specs,what makes the difference is that when you buy Mesa tubes,they are tested and sorted so the ones that will bias properly in your amp are the ones they sell you.You can buy a crate of 100 6L6's from a manufacturer,they can all be from the same production run,and if you install them in an amp and check the current draw,they wont all draw the same current in the very same amp,just the nature of tubes.I am sure Mesa discards or more likely sells off in bulk many tubes that dont fall into "spec" for their amps.Mesa tells you that their amps are "special" and cant be biased.That is a misleading statement by them to get you to buy their tubes.You can buy a set of Sovtek 6L6's that are the same as Mesa sells you for half the price,but you will have to bias the amp,that is the sole difference,Mesa selects tubes that will fall into a "safe" bias range in your amp.The bias scheme Mesa uses is nothing new,as an example Fender used it in their early Basssmans back in the '50's,many other amps used it as well.Without a bias pot to adjust the bias,a tech had to change a resistor to bias an amp,and it was done every day,and can be done to a Mesa just the same.It is better to replace that resistor with a pot so it is easier to adjust every time you change tubes.You wont mess up your amp experimenting with NOS power tubes,it just takes a little more work and understanding of what is going on in the power section.On the other hand there is nothing wrong with using new production tubes either,if like Rocky,you like them then that is all that counts.