[TrollDragon]

I now firmly believe in Cryo treated tubes.

Putting a tube in your freezer does NOT make it a cryo treated tube...

Give this a read...
https://www.effectrode.com/knowledge-base/cryogenic-treatment-of-tubes-an-engineers-perspective/

 

[triod750]

Putting a tube in your freezer does NOT make it a cryo treated tube...

Give this a read...
https://www.effectrode.com/knowledge-base/cryogenic-treatment-of-tubes-an-engineers-perspective/

I guess it was a joke and it was funny. Good idea to check for codes. Sometimes you need all help you can get.

 

[Cognomen]

I guess you're talking about 50L6GT, right? The only other reference beginning with "50L" I could find was an obscure Philips tube: 50L1D.

Yes

 

[Cognomen]

Putting a tube in your freezer does NOT make it a cryo treated tube...

Give this a read...
https://www.effectrode.com/knowledge-base/cryogenic-treatment-of-tubes-an-engineers-perspective/

I don't believe in cryo. It was a joke, risky business for postings.

 

[Cognomen]

I guess it was a joke and it was funny. Good idea to check for codes. Sometimes you need all help you can get.

Yes was a joke. Interesting that 10 minutes or so in the freezer tended to usually work better than longer time and repeating it sometimes helped also. Perhaps one needs just the right amount of condensation. The codes tend to appear briefly while the tubes warm up and the condensation is disappearing. Light cleaning sometimes helped. I just spray water and roll on something lint free rather than scrub or rub dry since that might remove any vestigial information. I had one tube that seemed to be covered with candle wax or something and used solvent and fortunately did not remove needed info. Come to think of it, though, sometimes freezing candlesticks with wax on them is a good way to make the wax somewhat brittle and easier to remove than dissolving it. Perhaps though it wasn't wax but some other gunk that got on the tube when its former equipment failed. It's a Japanese tube branded Curtis Mathes, a tv and electronics company. Tomorrow I'm going to broil some in the oven and blow torch a few too: pyro-treated tubes.

 

[Derivative]

Yes was a joke. Interesting that 10 minutes or so in the freezer tended to usually work better than longer time and repeating it sometimes helped also. Perhaps one needs just the right amount of condensation. The codes tend to appear briefly while the tubes warm up and the condensation is disappearing. Light cleaning sometimes helped. I just spray water and roll on something lint free rather than scrub or rub dry since that might remove any vestigial information. I had one tube that seemed to be covered with candle wax or something and used solvent and fortunately did not remove needed info. Come to think of it, though, sometimes freezing candlesticks with wax on them is a good way to make the wax somewhat brittle and easier to remove than dissolving it. Perhaps though it wasn't wax but some other gunk that got on the tube when its former equipment failed. It's a Japanese tube branded Curtis Mathes, a tv and electronics company. Tomorrow I'm going to broil some in the oven and blow torch a few too: pyro-treated tubes.

You can call it pre-warming, keep them in the oven at a low temp and they're always ready to use!

 

[Derivative]

Listening to the MK3 with IEMs for the first time today (Thieaudio Monarch II), not the bass and noise floor disaster I was fearing. Enjoyable listen in fact, although definitely lacking some of that detail/treble I get from solid state set-ups.
the Monarchs are hard to drive and in a strange way I think that's helping the sound with the MK3, in the sense that they're not so sensitive.

 

[barbazz]

Remember my questions about whether we could use dissimilar multisection tubes (triode-pentodes, diode-triodes, etc.) with LD? Well, I'm not much of a theoretical guy.

Here's some El-Menco 6CN7 (actually relabelled GEs) double-diode triodes happily playing.

 

[JazzVinyl]

Remember my questions about whether we could use dissimilar multisection tubes (triode-pentodes, diode-triodes, etc.) with LD? Well, I'm not much of a theoretical guy.

Here's some El-Menco 6CN7 (actually relabelled GEs) double-diode triodes happily playing.

Very nice!! And playing Philip Glass, no less!! Yeah!

 

[JazzVinyl]

With all due respect, there is something called in-rush current. When you turn on the amp, the tubes could draw up to three times the amount of current for a moment, and that is why you need the extra margin. If you have an amp meter hooked up you can see this.
Possibly there are heater circuits that avoid this with a slow start.

@mordy - I believe the inrush "problem" lies with the B+ (DC voltage/current) being supplied to the anode (plates) prior to the heaters being at a working temperature.
I was speaking in regards to the amperage that is avail to the heaters, not the B+ going to the anodes (plates). On the LD MK9 there is a relay that delays the B+ going to the anodes. So, it is never a problem in my amp.

I have had tube amps that made no distinction and sent the B+ to the plates the second you turn on the switch. However I personally never experienced a failure of the amp or power supply components in such an amp. So I do wonder if inrush is overstated as a "problem".

Here is a video on the subject of inrush:

 

[Cognomen]

Remember my questions about whether we could use dissimilar multisection tubes (triode-pentodes, diode-triodes, etc.) with LD? Well, I'm not much of a theoretical guy.

Here's some El-Menco 6CN7 (actually relabelled GEs) double-diode triodes happily playing.

Works well with the diodes floating/unconnected even though they are heated?

 

[barbazz]

Works well with the diodes floating/unconnected even though they are heated?

A little humm, but it works well. It is not dissimilar from what we do with the 6AV6 and the cut pins. They also share the heater between the diodes and triode.

I need to try to strap pin 9 (Heater Mid-Tap) to the heater and see if it gets better.

 

[triod750]

This looks like the good old days in the Little Dot tube rolling thread when almost anything seemed possible. Bravery!

 

[TrollDragon]

This looks like the good old days in the Little Dot tube rolling thread when almost anything seemed possible. Bravery!

I was just thinking the same thing, those were great times!

 

[TrollDragon]

A little humm, but it works well. It is not dissimilar from what we do with the 6AV6 and the cut pins. They also share the heater between the diodes and triode.

I need to try to strap pin 9 (Heater Mid-Tap) to the heater and see if it gets better.

My first guess would be the 3 feet of wire connecting the tube that's causing the hum.