JJ 6L6GCs... WTF?

[daz]

Bruce, aside from what i said above (used many JJ's from euroT w/o any bad ones where i work) i've used them personally for many years, tho mostly the 84's and 6V6. But even there never any bad one. In fact, i don't think i've ever seen one tube from eurotubes go bad after any amount of time. I really think you should try some stock from ET then if it's good call Bob and talk to him about making them your supplier and see what kind of a deal you can get. They've always been good to deal with and if i liked more of thier tubes thats all i'd buy personally. It's all we use at work right now. Now that i've found i love thier 6L6 and that my main amp sounds great with them i'll be using them for now on.

[big_teee]

Bruce, aside from what i said above (used many JJ's from euroT w/o any bad ones where i work) i've used them personally for many years, tho mostly the 84's and 6V6. But even there never any bad one. In fact, i don't think i've ever seen one tube from eurotubes go bad after any amount of time. I really think you should try some stock from ET then if it's good call Bob and talk to him about making them your supplier and see what kind of a deal you can get. They've always been good to deal with and if i liked more of thier tubes thats all i'd buy personally. It's all we use at work right now. Now that i've found i love thier 6L6 and that my main amp sounds great with them i'll be using them for now on.

Do you pay those Eurotube website Prices?
That looks awful pricey for a Biz to buy from.
Apparently they don't want business accounts.
Practically everyone is cheaper than what I saw there?
T

[Leo_Gnardo]

Practically everyone is cheaper than what I saw there?
T

If the "good" tubes are to be had from one particular distributor, and dodgy ones from everyone else, consider what price do you assign to frustration: extra time faffing with what should be a working amp then emailing, phoning, packing, cost of return shipping and not being able to trust your inventory plus worrying about customers returning gear for re-repair, and loss of good reputation. If that's the case, which source is cheaper?

[Jazz P Bass]

Plus, if a supplier is truly going to test the tubes before resale, and other suppliers won't, shouldn't they cost more?

[bob p]

^ That puts the "V" in "VAR".

The cheapest widget isn't always the one with the lowest price.

[Leo_Gnardo]

Plus, if a supplier is truly going to test the tubes before resale, and other suppliers won't, shouldn't they cost more?

Whups, left one out, thanx JPB! Hadn't had my first coffee yet, my flimsy excuse. note lack of coffee stain on smiley's smile.

[big_teee]

What about the Tung-Sol 6L6 STR?
I've heard good reviews on them.
I may try a set in the new Hy-Gainer I'm building.
I'm looking for something besides the Js for a change myself!
T

[big_teee]

Have a Nice Day!
T

[Jazz P Bass]

What a load of marketing bullsh*t.

[big_teee]

What a load of marketing bullsh*t.

I agree, but what do you think of the soft and hard vacuum, of various brands?
Haven't heard that line before.
I was trying to get opinions of various tubes like the Tung-Sol 7581.
Anyway, I was just passing on what I got back.

[Jazz P Bass]

I have not heard of the 'Hard /Soft' vacuum term.
What I do understand to be fact is the typical vacuum time (being pulled down) is nowhere near as long as in the heyday of tube manufacture.
(something on the order of 3 hours as compared to 12)
So if one tube is run on the machine longer than another I guess that would indicate a 'Hard' vacuum.
Well, harder.

[Bruce / Mission Amps]

I have not heard of the 'Hard /Soft' vacuum term.
What I do understand to be fact is the typical vacuum time (being pulled down) is nowhere near as long as in the heyday of tube manufacture.
(something on the order of 3 hours as compared to 12)
So if one tube is run on the machine longer than another I guess that would indicate a 'Hard' vacuum.
Well, harder.

Hard or soft is a very old term.. us old geezers probably still use it.
Basically in a nut shell, ... a soft tube, usually a well worn tube acts like a soft tube, draws more idle current with any given bias condition, has less total power output and can be driven into compression a bit easier then a hard tube.

[Jazz P Bass]

I have tested used, worn out tubes & they the loss in the output voltage amplitude usually goes hand in hand with less current draw.

[km6xz]

Hard and soft vacuum are still valid terms in vacuum technology but Bruce is right, it was an everyday term for old timers like us.
Hard referred to two main factors, the amount of total gas material left in the same, and the chemical composition of the material in the space. Another factor is mean free path. This is how dispersed the remaining matter is. How far an atom travels before coming into proximity of another atom.
There is no place where a vacuum is total because particles spontaneously pop into existence according to quantum theory.
High vacuum is the term used outside of electronics to describe a very low number of gas atoms, at very low gas pressure, what we call "hard" vacuum. High vacuums are indeed very low density places. A hard vacuum tube might have 1/10^-7 the number of atoms per cm^3 than a light bulb, A soft vacuum tube might be 1/10^-5 the number of atoms per cubic cm..
Whether is is good or bad depends on what those atoms are as much as how many there are.
Hard vacuums in tubes are associated with longer useful life, and more consistent operating characteristics. Deep space is a much better vacuum than what can be created on earth. Vacuum tubes, if build in space, would need no glass envelope and be able to dissipate more power, have a harder vacuum and have less contaminating atoms and handle higher potentials between elements before arcing. They would simply be elements hanging in space with no container.

[bob p]

I thought the whole letter was nothing but BS, with this being the most offensive statement of them all:

"Tubes are not better or worse now than through out history."

Obviously, this fellow is a purveyor of new production tubes, who wants his customers to not even contemplate comparing the quality of new production re-branded tubes the the older tubes to which they claim to be equivalent. He wants us to turn a blind eye to the performance standards that companies like RCA used to enforce in order for other manufacturers' tubes to be allowed to bear an RCA-trademarked model number designation.

RCA used to provide very strict standards about what type of tube could be sold bearing the 6L6 designation. That's not true today -- today there is no real oversight. In the absence of RCA's oversight, today anyone can take a tube that was never designed to be a 6L6, and sell it as a 6L6 without ever bothering to prove that it is actually equivalent in terms of specifications, build quality or durability. IMO what we buy as 6L6 tubes today would be a lot more reliable if they all had to pass RCA standards in order to bear the designation "6L6".