so I fell for the snake oil

[cbass]

I bought some of these for my 100 watt super drive. http://www.cryoset.com/catalog/product_ ... c10d2543fa
They sound great .
Only a little more than what they cost from Russia . I figure if they claim cryo is so great that probably test the tubes pretty good . tightly matched from '78 they claim 24 hour burn in so well see if they drift.
Running 530volts on the plates jjeel34s won't hang .

[matt h]

(deleted)

[cbass]

Now we'll see how they handle the voltage JJ e34ls and el34s can't even biased to 50%. the JJ 6l6s I had seem to handle it fine but they are barely used from over 10 years ago. I don't trust the new ones at all

[matt h]

(deleted)

[cbass]

Well I just think JJ tubes suck anymore . I ran a pair of jap 34s just fine rca 6l6s just fine Chinese 6l6s just fine . a couple of the jjs blew up as soon as I flipped the switch out of two quads I got 2 decent tubes

[cbass]

Matt so you think a 25 watt 470ohm or something in series with the choke would help. I'm already running ng 1ks on the screens . I don't want to alter the sound.this thing freaking rips. I've found big resistors before the screens pretty spongy feeling . that's not whqt I want here

[matt h]

(deleted)

[Cantplay]

I had a couple dozen Amperex 6922(pinch waist) cryoed. I tested them before and after. They all tested 2-3% higher after.

Cryo causes compression past elastic deformation and results in change to grain and crystal structure. This is easily proven with cutting tools.

Not every change is an improvement, so you'll have to decide if its a good match for your gear or musical style.


John

[cbass]

Hi John, I bought the tubes cause it was the best price from a US seller. I figure if he's claiming cryo is all that they probably test the tubes real good to begin with. I believe he uses a maximatcher . if cryo really helps things then all the better. Yes I know cryo is effective on tool steel and other metals. I'm just a little skeptical about it's effectiveness on tubes. If you say they test better afterwards then that's a good thing for me

[cbass]

So I don't know what your screen voltages are, therefore can't really tell you what value you'll need.

But right now, your screen resistors are connected to your second filter cap node (like, you might have a stack of caps wired in series/parallel for your first node). right? right.

If you throw a big resistor in series with your choke (assuming a big ole series power supply, which it probably is), you'll have all of the current for the rest of your amp (screens, PI, preamp, etc) through that resistor--so it'll need to account for that, but also it'll drag your voltages throughout the amp down too (which may or may not be desirable)

Between that filter cap, and your screen resistors, include another resistor. Use something like a 1k 10W to knock down some serious voltage. If your plates are north of 550, it seems like your screens are probably right up there.

This lets you reduce the value of your screen resistors. This'll take a lot of the "squishiness" away.

I'll have to take some more mesurments and get them biased when I get a chance . power amp is pretty much your standard Marshall 100 watter but yes the screens are right up there. I'm hoping that these tubes will take it they sound better than 34s in this amp anyway.

[Structo]

Let us know how the tubes work for you.

I was trying to find a data sheet for the 6P3S-E.

The one I found said the anode voltage was 250v.

http://www.tubes.ru/techinfo/HiFiAudio/6p3s.html

Are these tubes from the '70's?

[cbass]

The 6p3s-e is the supposed to be the same tube as the sovtek 5881 .that's what came in Naylor super drives . they ran bout 500 volts on the plates. I've got bout 535
I think they are from 1978 they came with really cool original boxes .
The 6p3s with no e supposedly sucks and can't even handle 6v6 applications

[Zippy]

Cryo causes compression past elastic deformation and results in change to grain and crystal structure. This is easily proven with cutting tools.

That something is "easily proven with cutting tools" doesn't translate to other applications unless they use the same materials.

Those changes in grain structure and phase are dependent on the composition and prior processing. In many instances, the best you can hope for is stress relaxation.

[cbass]

Its take ng -70vdc to get the bias around 60%

[romberg]

Cryo causes compression past elastic deformation and results in change to grain and crystal structure. This is easily proven with cutting tools.

That something is "easily proven with cutting tools" doesn't translate to other applications unless they use the same materials.

Those changes in grain structure and phase are dependent on the composition and prior processing. In many instances, the best you can hope for is stress relaxation.

But... but... what about the "micro detail with an increase in speed"? That truly must be more than hype!

Seriously, I agree with the logic in that the tubes may be matched and QCed a bit more (or bad ones reflect on the chilling). And the price is not bad even if this is all you are paying for.

Mike