Is there anyway... (buying tubes content)

[dudleydawson]

...to buy tubes at the small neighborhood music store and know whether or not they are appropriate for use in my boogie?
at least two local music shops have some JJ's and ruby's. and i know that GC has them as well...

please excuse my relative newbie-ness

do they have readings on the boxes or anything like that?
or would i need to go through a third party like doug's or eurotubes who tests them to ensure they are within spec?

i'm just doubting anyone at GC will have any clue what i am talking about... last time i went in for preamp tubes they looked at me like i was the 1st a**hole who ever tried changed a tube.

 

[MrMarkIII]

Only the large power tubes need to be matched to your particular amp. Not so with the pre-amp tubes.
You should browse through the "TUBES" sub-forum. Much info available there.

 

[dudleydawson]

should have been more clear - i'm looking for power tubes.

my question was more about the purchase...
whether i could look at a wall of JJ's and be able to pick out the ones which fall within Mesa's bias specs... (i.e. any sort of technical info on packaging...)

moot point i guess.
local GC only has mesa-brand and groove tubes.
not what the guy on the phone told me... :roll:

 

[moondawg]

should have been more clear - i'm looking for power tubes.

my question was more about the purchase...
whether i could look at a wall of JJ's and be able to pick out the ones which fall within Mesa's bias specs... (i.e. any sort of technical info on packaging...)

moot point i guess.
local GC only has mesa-brand and groove tubes.
not what the guy on the phone told me... :roll:

My first post on the boards..
It seems to me you are in the "gray" zone that every boogie owner is in who has not yet installed a bias pot...

My hat is off to Mr. Smith for making great amps and then selling folks on the idea that they MUST use his tubes... brilliant!!

I know it will be a pain to bring the amp to a tech to bias your tubes every once in a while. But look at the chioces that will open up to you. Moreover if you are careful you can turn the pot yourself and as long as the plates don't have any glow you can dial in your best sound with a particular tube set.

IMHO I don't care what it says on the tubes... I need that pot to have the freedom to dial in a sound.

 

[volatileNoise]

Nonsense, surprised none of the more knowledgable guys haven't replied to this thread...

Go buy a matched quad or pair (if only a 50w amp) and stick them straight in the amp (just buy from a knowledgable dealer and they should be able to pick out a set for you that will suit your Mesa nicely) biasing is not required unless you are going to a larger tube type/different style of tube altogether, which is not really for newbies to be considering anyway.

My advice is to grab a set of Winged C or something similar in either 6L6 or EL34, but be sure to have the bias switch on the back of your amp set to suit.

And try not to get finger prints on your new tubes, give then a quick clean with a soft cloth before firing up the amp.

Nothing more to worry about, it's that simple.

 

[stokes]

volatileNoise,your response is misleading.You say "Go buy a matched quad or pair (if only a 50w amp) and stick them straight in the amp",this would imply any set will work.They have to be "pre-graded" in order to fall into the usable range of current draw,but you do say "just buy from a knowledgable dealer and they should be able to pick out a set..." He is asking if he can avoid buying from someone who pre tests and grades them just by looking at numbers or such on a set of "off the rack" tubes,which you shouldnt do unless you have an adjustable bias pot and can check and set the bias."My advice is to grab a set of Winged C or something similar in either 6L6 or EL34, but be sure to have the bias switch on the back of your amp set to suit" Only if you get them from a supplier who tests and grades them. Fingerprints? Unless you are worried about CSI tracking you down,fingerprints on the tubes wont hurt anything.

 

[kdorsey]

Fingerprints? Unless you are worried about CSI tracking you down,fingerprints on the tubes wont hurt anything.

That's not accurate, either. Body oils deposited on the glass by fingers will generate a hot spot that can lead to a premature degradation of the tube. It is true that the typical high temps of tubes can evaporate the oil over time, but like a halogen bulb, the temperature inconsistency can produce advanced aging on that part of the adjacent internal components. That's not enough to worry about if you routinely change your power tubes every 6 months, but if you just two-bite slammed a Big Mac and a large fries, it would be a good idea to wash your hands first. :mrgreen: Common sense prevails...a simple wipe of the tube after handling is not a bad practice.

 

[stokes]

Dont change my tubes every 6 months,have been working with tubes for over 35 years and have never seen or heard of tubes dying from fingerprints,and have never polished a power tube.Power tubes in my amps typically last 2 years or more,biased on the hot side,fingerprints and all,no "hot spots",many last me longer than 2 years,I have 2 sons who play in a combined 7 bands and all the amps see a lot of use. I dont use current production tubes myself,but I've never installed them for a customer and had them come back because of fingerprint damage,so I have to doubt the current manufacturers are using some extremely thin,fragile glass these days.Vacuum tubes are not halogen bulbs,which can be damaged by fingerprint oil,this is just another internet myth.And I wouldnt even touch the handle of an amp if I had McD's grease on my hands,btw,that analogy is a bit extreme,I think.If you guys want to polish your tubes,go right ahead,it wont hurt anything,but please dont pass this practice off as a necessity.People are finicky enough,I dont need idiots coming back for a re-tube cause they see fingerprints on their tubes.

 

[dodger916]

People are finicky enough,I dont need idiots coming back for a re-tube cause they see fingerprints on their tubes.

Hey stokes: why not market a line of "tube gloves" - a combination oven mitt (for handlng hot tubes) that also polishes them? :lol:

 

[volatileNoise]

"My advice is to grab a set of Winged C or something similar in either 6L6 or EL34, but be sure to have the bias switch on the back of your amp set to suit" Only if you get them from a supplier who tests and grades them. Fingerprints? Unless you are worried about CSI tracking you down,fingerprints on the tubes wont hurt anything.

Bullsh*t on the first comment, example - If you think that buying say a set of Winged C 6L6 tubes, are going to vary hugely in specification, you are wrong, they will all fall into a certain range that has passed manufactured specification before being released into the market. SOME may have a test specification slightly closer to Mesa's factory rated tubes, who cares? I didn't care, and threw an off the shelf set straight into my Dual Rec and it has never sounded better.

Bullsh*t again on the second comment, maybe won't cause any problem for sometime, but just like a halogen globe that has been touched by peoples fingers it can create a hot spot on the glass surface, and can end up having a shortened life span, though possibly not as extreme a problem as the halogens, that probably run hotter than a tube.

Thirdly, I don't give a **** what you've done over 35 years, I didn't say polish the fu*king things, I said to simply clean off any oily finger prints with a cloth, might give the tubes an extra few months of life and hopefully lessen the chance of an unlucky failure, who knows? And who cares really.

 

[stokes]

Who cares?So why you gettin' so fired up?The glass has absolutely no electrical properties,so how,even if there is a hot spot,is that going to shorten the life of a tube.Please do explain exactly what type of failure you imagine.If you've ever seen the effect of a fingerprint on a halogen bulb,and I doubt you have,it gets so hot and the glass is so thin that the glass becomes etched and cracks causing sudden failure.A manufacturer makes tubes and sells them as lots,they do vary greatly even within the same production run,they are then tested for current draw and grouped together by the retailers such as Mesa and GT by the current draw.Just because you got an "off the shelf" set that happened to fall into a safe range is luck.It is just plain bad advice to tell someone to ignore what any tech will tell them about tubes and bias.You son,are talking out your ***.Read a few books.

 

[volatileNoise]

If you've ever seen the effect of a fingerprint on a halogen bulb,and I doubt you have,it gets so hot and the glass is so thin that the glass becomes etched and cracks causing sudden failure.

Actually I have, I am an automotive mechanic from way back, and the glass actually doesn't generally crack, the glass of small halogen globes isn't as thin and fragile as you may like to think.

And the glass has nothing to do with any of the electrical properties what so ever, not of a globe or a tube. You are missing the point, I originally also mentioned in my original reply this - (just buy from a knowledgable dealer and they should be able to pick out a set for you that will suit your Mesa nicely)

But as the amps are biased relatively cold you are very unlikely to have much of an issue, from my experience, and from the knowledge that others have shared over various discussions.

Books are out of date, there is more knowledge readily available online, go fly a kite. :lol:

 

[stokes]

"Books are out of date, there is more knowledge readily available online, go fly a kite". This shows what you really dont know about the inside of a tube amp.Basically very little has changed in a tube amp,or the technology in tube circuits,in over 50 years.For all the good info on the internet,there is twice as much misinfo,such as "fingerprints are no good for the tubes",like I said,go read a book or two before you speak.I bet your total experience with tubes is just what you've read on the internet,oh excuse me,you've probably actually touched a half dozen set of tubes in your vast expeperience.As for the halogen thing,I worked in a photo lab for over 10 years in the 60's and '70's and we used halogens in the copy cameras.We used to play a joke on one of the guys by touching the bulb in his set-up and watch it scare the crap out him when it quite predictably exploded when he would turn it on.Auto halogens are much tougher,and burn much cooler than the ones intended for use indoors or in photo applications,but you're a mechanic,you should know that.Or did you not get up to that page on the internet.
"But as the amps are biased relatively cold you are very unlikely to have much of an issue, from my experience, and from the knowledge that others have shared over various discussions".Again,in your vast experience,you've never seen the effects of crossover distortion in an amp with tubes that sit way too cold?I have one on my bench right now,belongs to one of the posters here,as a matter of fact.
So please do explain to me exactly how a fingerprint,or a hot spot will shorten a tubes life.Because I have tubes that the ink has burned,that would constitute a "hot spot",no? Well those tubes have been in that amp since about 1978,fingerprints included,funny thing tho,I cant see any burnt prints,or hot spots other than the once white,now brown labeling.And surprise,they still work and sound fine.

 

[MrMarkIII]

"Polishing your 6L6".
Is that what you kids are calling it these days?
(Don't over-do it, you'll go blind)
:lol: :lol: :lol:

 

[domct203]

I'm almost afraid to post in this thread :shock:

This is simply my own personal experience and is not directed at anyone.

I took some JJ E34L's that run at about 70% MPD in my Roadster and through them in my MKV. The inside pair ended up at 105% MPD, and would have red-plated immediately if I tried to play the amp that way. This is the reason why I own a bias probe. Even when I ask a vendor for tubes rated to run in a Mesa (as these E34L's were), I always double check the bias.

You should not just throw any set of power tubes in an amp and just hope for the best. At least verify where the tubes idle current (bias) is before you embarrass yourself at a gig with a blown tube or two, popped fuse and/or burnt screen grid resistor. Nothing worse than setting up a $3K rig then asking to borrow the opening bands valvestate 'cause you blew up your amp.

My $0.02.

Dom

 

[domct203]

"Polishing your 6L6".
Is that what you kids are calling it these days?
(Don't over-do it, you'll go blind)
:lol: :lol: :lol:

LMFAO!

Dom

 

[yeti]

wow
this post went south in a strange way.

i think the bias pot is the way to go....but, thats just me.

for some people, it might not be. if it seems intimidating, just stick with what mesa recommends and skip the mom and pop store..you''ll save yourself much headache in the fyuchah!

the fyuchah!

 

[stokes]

+1 on the bias check,Dom,but the adjustable bias is the way to go,I've seen supposedly "matched and graded" tubes by Mesa vary by more than +/- 25ma's within the same color.Even those crap Sovtek and other current production tubes can be made to sound decent with a little tweaking.

 

[domct203]

+1 on the bias check,Dom,but the adjustable bias is the way to go,I've seen supposedly "matched and graded" tubes by Mesa vary by more than +/- 25ma's within the same color.Even those crap Sovtek and other current production tubes can be made to sound decent with a little tweaking.

14 months of warrenty left then I'm in there with an adjustable bias mod!

Dom

 

[stokes]

14 months of warrenty left then I'm in there with an adjustable bias mod!

Dom[/quote]
Better read the fine print,I think they can void your warranty if you check your bias.