Pulled the trigger on Elrog 300B for the Golden Gate DAC

Dracule1 · « **Reply #20 on:** 22 Oct 2015, 12:32 pm »

Quote from: FullRangeMan on 22 Oct 2015, 09:58 am

STM this procedure are correct.
All tubes in brokein need about a day of rest after the use.

STM? What does that mean?

sfox7076 · « **Reply #21 on:** 22 Oct 2015, 01:21 pm »

I am not sure why they need a day of rest. And why only over time? When you turn a tube on, the current inrush spikes. On some tubes, it may be amps higher than the normal operating point. Shutting it on and turning it off would do more damage if it needed some form of break in. Heating it over numerous hours would do whatever burn off needed to be done without the current inrush stress on the filament. The latter statements assume a fixed voltage heater element circuit. If there is going to be filament failure, it will be on turn on or due to mechanical shock...

Dracule1 · « **Reply #22 on:** 23 Oct 2015, 01:11 am »

Quote from: sfox7076 on 22 Oct 2015, 01:21 pm

I am not sure why they need a day of rest. And why only over time? When you turn a tube on, the current inrush spikes. On some tubes, it may be amps higher than the normal operating point. Shutting it on and turning it off would do more damage if it needed some form of break in. Heating it over numerous hours would do whatever burn off needed to be done without the current inrush stress on the filament. The latter statements assume a fixed voltage heater element circuit. If there is going to be filament failure, it will be on turn on or due to mechanical shock...

I agree with you. But I remember Emission Labs recommends burn in of only 3 or 4 hours at a time. I didn't get their reasoning.

sfox7076 · « **Reply #23 on:** 23 Oct 2015, 01:19 am »

I could see it if it was bring the operating voltage on the plate and grid slowly, but that isn't what we have here.

Quiet Earth · « **Reply #24 on:** 23 Oct 2015, 02:32 am »

Frequently asked question #2 from the Emissions Labs website : http://www.emissionlabs.com/diversen/FAQ.htm

It has to do with formatting the filament during the first 50 to 100 hours of the tube so the filament will last longer. That means run the tube for 4 or 5 hours, then let it cool for a bit. Then run them another 4 or 5 hours, cool, repeat, until you reach 50 to 100 hours.

If filament life is an issue with these Elrogs, then this is something worth trying. (IMO)

FullRangeMan · « **Reply #25 on:** 23 Oct 2015, 02:40 am »

Quote from: Dracule1 on 22 Oct 2015, 12:32 pm

STM? What does that mean?

Seems to me.

FullRangeMan · « **Reply #26 on:** 23 Oct 2015, 03:49 am »

Quote from: sfox7076 on 22 Oct 2015, 01:21 pm

I am not sure why they need a day of rest. And why only over time? When you turn a tube on, the current inrush spikes. On some tubes, it may be amps higher than the normal operating point. Shutting it on and turning it off would do more damage if it needed some form of break in. Heating it over numerous hours would do whatever burn off needed to be done without the current inrush stress on the filament. The latter statements assume a fixed voltage heater element circuit. If there is going to be filament failure, it will be on turn on or due to mechanical shock...

I am not sure why they need a day of rest.
For the chemical reactions of the getter fully happen until the end of the process.
Inside a valve there is millions of molecules of oxygen and other gases. Who will clean this is the getter to made a vaccuum that have safe condition to the tube operate in hi temp.
Unfortunately the getter remains active only about six months, after this period it is necessary to make a new burnin.
And why only over time?
Not sure how many hours from burnin is recommeded for the Elrog 300B, together w/the tube must came a paper informing this very important info.
If the builder dont inform this info it is a very bad sign for the people that own this expensive tube.
When you turn a tube on, the current inrush spikes.
The worst thing you can do for a valve is put it into an amplifier without softstart and without two power on switches.
In this adverse working conditions a chinese big triode lasts only 500 hours and a robust Russian GM70 about 1200/1500 hours.
Even a 6C33 used inside a MIG25 jet need softstart, in this case (military use where cost is no object) its recommended 120seconds minimum time.
Unfortunately its only mentioned in 1 data sheet made by Michael Boele:
http://www.jogis-roehrenbude.de/Russian/6C33C/6C33C-B-6S33S-VExtendedDatasheetMB.pdf
(Warm-up time to 90% emission 120 s.)

To put a right tube amp in great shape the power off procedure also need ''softstart'' or wouls say ''softpoweroff'', I dont know how implement it unless with a simple Variac as used by expensive Joule-Electra OTLs.

sfox7076 · « **Reply #27 on:** 23 Oct 2015, 07:21 pm »

I am not sure I agree with you on any of the points regarding getter and the filament, but that's ok. I do agree that putting a lot of voltage on the plate before warm up of the cathode is a bad idea.

Dracule1 · « **Reply #28 on:** 26 Oct 2015, 01:25 am »

I have about 34 hours on the Elrogs on my Lampi. Sorry to say I'm quite disappointed with the sound. Initially, I had great hopes. When I first plugged them in, I heard buttery smooth sound with accurate timbre. However, they were not as transparent, dynamic, tight in the bass, or extended in the highs as the Psavane 101Ds or the TJ Full Music 300Bs. Even with break in, the overall sound has not changed. The music feels slow with the Elrogs, and they are the least revealing of the tubes I have. Seems like the harmonics are somehow truncated. Not sure how to explain this given all the positive reviews they've received. I'm wondering if my tubes are either defective or needs more break in.

SearchOfSub · « **Reply #29 on:** 26 Oct 2015, 05:06 am »

Quote from: FullRangeMan on 23 Oct 2015, 02:40 am

Seems to me.

lol, is this a new word, like ITS (I think so) or IMG (In my book) - just made these up RN. (right now) - sorry I couldn't resisy, my apologies.

FullRangeMan · « **Reply #30 on:** 26 Oct 2015, 10:11 am »

Quote from: Dracule1 on 26 Oct 2015, 01:25 am

I have about 34 hours on the Elrogs on my Lampi. Sorry to say I'm quite disappointed with the sound. Initially, I had great hopes. When I first plugged them in, I heard buttery smooth sound with accurate timbre. However, they were not as transparent, dynamic, tight in the bass, or extended in the highs as the Psavane 101Ds or the TJ Full Music 300Bs. Even with break in, the overall sound has not changed. The music feels slow with the Elrogs, and they are the least revealing of the tubes I have. Seems like the harmonics are somehow truncated. Not sure how to explain this given all the positive reviews they've received. I'm wondering if my tubes are either defective or needs more break in.

The praises were from buyers or from paid reviewers?
The original WE300B cathode was made with oxide wire,
not tungsten thoriated though. Maybe 5V not suffice to
heat TT cathode to 2500ºC.

sfox7076 · « **Reply #31 on:** 26 Oct 2015, 01:10 pm »

O1s have a Thoriated Tungsten element that has run for 100 years at 5v 1A. 01As only have a 250ma draw. 300B should be 1.2A. If sounds bad, the Tungsten isn't the issue. Resistance might be. Or maybe they just stink.

Dracule1 · « **Reply #32 on:** 26 Oct 2015, 07:18 pm »

Quote from: sfox7076 on 26 Oct 2015, 01:10 pm

O1s have a Thoriated Tungsten element that has run for 100 years at 5v 1A. 01As only have a 250ma draw. 300B should be 1.2A. If sounds bad, the Tungsten isn't the issue. Resistance might be. Or maybe they just stink.

By resistance, You mean possible impedance mismatch between DAC and preamp/amp?

sfox7076 · « **Reply #33 on:** 26 Oct 2015, 10:00 pm »

No, I meant the resistance of the tube filament. In theory, the tube should draw 1.2Amps at 5 volts. That means that the resistance of the circuit would be 5 volts/1.2 Amps. As the tube heats though, the resistance goes up. This generally means that the current draw drops. But Not sure how the Elrog's do it.

Dracule1 · « **Reply #34 on:** 26 Oct 2015, 11:50 pm »

My amp has input impedance of 100 kOms and has built in stepped attenuator. I'm going to try hooking my GG DAC directly into the amp bypassing my passive preamp. In some situations, this can dramatically improve the sound. I also spoke toe George a TubesUSA. He recommended trying different types of rectifier tubes including 5R4, 5R4GY, GZ34 and GZ37. He told me to stay away from 5AR4 which draws 4 amps and is too much. I'm currently using the Psvane 274B replica. I also have the EML 5UG that came with DAC which I haven't tried with the Elrogs. I also have a Brimar 5Z4GY coming soon. It was recommended by a fellow Audiogoner who used it in the Lampizator.

sfox7076 · « **Reply #35 on:** 27 Oct 2015, 03:45 am »

No idea who told you the 5AR4 draws 4 amps. It draws 1.9 amps... 5R4 is 2 Amps.... Not sure of the issue.

Dracule1 · « **Reply #36 on:** 27 Oct 2015, 03:58 am »

Quote from: sfox7076 on 27 Oct 2015, 03:45 am

No idea who told you the 5AR4 draws 4 amps. It draws 1.9 amps... 5R4 is 2 Amps.... Not sure of the issue.

George at TubesUSA told me not to use the 5AR4 because of the high current. May be he misheard me and was thinking about a different tube.

Dracule1 · « **Reply #37 on:** 27 Oct 2015, 03:59 am »

Doesn't matter, I found the problem. I'm so happy!

sfox7076 · « **Reply #38 on:** 27 Oct 2015, 12:32 pm »

What was the issue?

Dracule1 · « **Reply #39 on:** 27 Oct 2015, 01:06 pm »

Quote from: sfox7076 on 27 Oct 2015, 03:45 am

No idea who told you the 5AR4 draws 4 amps. It draws 1.9 amps... 5R4 is 2 Amps.... Not sure of the issue.

It was a misunderstanding. George at TubesUSA thought I said 5AU4 when I actually said 5AR4.