Vali 2 tube rolling
Nov 29, 2019 at 12:45 PM Post #4,816 of 6,436
Hmmmm. I have a BH Crack kit that I have yet to assemble. Maybe that'll do nicely as a tube buffer. :thinking:

The BH Crack has no pre-amp out per se, some folks just come out of the TRS jack into dual RCA connectors but I have added that circuit to a couple I built.
 
Nov 29, 2019 at 12:52 PM Post #4,817 of 6,436
Doh! Well, I'm sure I can find a source for that adapter when the time comes.
 
Nov 29, 2019 at 1:24 PM Post #4,818 of 6,436
If you do, I claim dibs on your 7 tubes.

:stuck_out_tongue_closed_eyes::stuck_out_tongue_closed_eyes:

?

You do realize this entire thread is kind of stupid right? Swapping 7 different tubes is a complete waste of time and resources. Get a volt meter, figure out the operating conditions of the tube in the vali. Figure out the plate voltage, and the supply voltage. Then figure out how the tube is being biased and what the bias voltage is.

Once you have these parameters, start looking at tube data sheets and figure out what tube is the most linear and well loaded at those parameters.

For instance if the tube is biased at lowish current and low bias voltage, I would run away from the ECC88 and 6922 type tubes. The 6bq7a is a better tube at lower operating conditions.

However if schiit biased the tube for a bit more current (something in the 15ma range), then the 6922 COULD be better because of its lower plate resistance.

The other catch is to understand that as any of these tubes approach the 0v grid line, all of these tubes start to fall apart. A tube with a higher amplification factor could help you crank the volume up higher whilst staying away from the 0v gird line and keeping distortion at a minimum.

Blindly swapping tubes around without understanding the circuit is just throwing good money after bad.
 
Nov 29, 2019 at 1:24 PM Post #4,819 of 6,436
That sounds about right, after you summarily declared all tubes that I sent to you for testing as bad and offered to 'dispose' of them for me. And then I went and did something even more stupid -- I bought a tester from you which seems to fail every tube I ever test on it.

I'm seeing a trend here... and its not that I'm gullible. :unamused:

You bought a tester? You should've held out for a tester box. From what I've gathered box rolling is the in thing now:grinning:
 
Nov 29, 2019 at 1:40 PM Post #4,820 of 6,436
?

You do realize this entire thread is kind of stupid right? Swapping 7 different tubes is a complete waste of time and resources. Get a volt meter, figure out the operating conditions of the tube in the vali. Figure out the plate voltage, and the supply voltage. Then figure out how the tube is being biased and what the bias voltage is.

Once you have these parameters, start looking at tube data sheets and figure out what tube is the most linear and well loaded at those parameters.

For instance if the tube is biased at lowish current and low bias voltage, I would run away from the ECC88 and 6922 type tubes. The 6bq7a is a better tube at lower operating conditions.

However if schiit biased the tube for a bit more current (something in the 15ma range), then the 6922 COULD be better because of its lower plate resistance.

The other catch is to understand that as any of these tubes approach the 0v grid line, all of these tubes start to fall apart. A tube with a higher amplification factor could help you crank the volume up higher whilst staying away from the 0v gird line and keeping distortion at a minimum.

Blindly swapping tubes around without understanding the circuit is just throwing good money after bad.

Some of us happened to talk to Jason Stoddard before swapping tubes and he designed the amp. Thanks for your input though. :)
 
Nov 29, 2019 at 1:41 PM Post #4,821 of 6,436
?

You do realize this entire thread is kind of stupid right? Swapping 7 different tubes is a complete waste of time and resources. Get a volt meter, figure out the operating conditions of the tube in the vali. Figure out the plate voltage, and the supply voltage. Then figure out how the tube is being biased and what the bias voltage is.

Once you have these parameters, start looking at tube data sheets and figure out what tube is the most linear and well loaded at those parameters.

For instance if the tube is biased at lowish current and low bias voltage, I would run away from the ECC88 and 6922 type tubes. The 6bq7a is a better tube at lower operating conditions.

However if schiit biased the tube for a bit more current (something in the 15ma range), then the 6922 COULD be better because of its lower plate resistance.

The other catch is to understand that as any of these tubes approach the 0v grid line, all of these tubes start to fall apart. A tube with a higher amplification factor could help you crank the volume up higher whilst staying away from the 0v gird line and keeping distortion at a minimum.

Blindly swapping tubes around without understanding the circuit is just throwing good money after bad.

Bill was joking. Sadly, I have approx.200 tubes and my refurbished and calibrated BK tester was a bargain. I tend to stick with tubes that closely align with the design of the amp in which they will be used. I'm no expert and rely on the tester to tell me if the tubes are strong and balanced.

Btw- I'm not a hoarder - I'm a collector, dammit!
 
Nov 29, 2019 at 2:16 PM Post #4,823 of 6,436
Did he tell you guys what the operating conditions were or did he tell you what his opinions were?


He mentioned which tube types matched up. I am not sure where you got 7 types.

The biggest concern was 6SN7’s as I recall.
 
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Nov 29, 2019 at 2:18 PM Post #4,824 of 6,436
You do realize this entire thread is kind of stupid right?

Then either you enjoy reading stupid stuff or you're just trolling.

Ignore set.
 
Nov 29, 2019 at 2:38 PM Post #4,825 of 6,436
Then either you enjoy reading stupid stuff or you're just trolling.

Ignore set.
Come on. The fella has a scientific method of determining what other people should enjoy hearing. No wonder he has 34 likes for 500+ posts.
 
Nov 29, 2019 at 2:47 PM Post #4,826 of 6,436
Has anybody tried the https://www.thetubestore.com/rca-6cg7-6fq7?cur=CAD?

I just read on the site that can't be named that it was a pretty good for Both the Lyr 3 and Vali 2.

I got some new toys recently and haven't used this amp in weeks. I really do have to get back into it.

Shane D
 
Nov 29, 2019 at 4:00 PM Post #4,827 of 6,436
Then either you enjoy reading stupid stuff or you're just trolling.

Ignore set.
Come on. The fella has a scientific method of determining what other people should enjoy hearing. No wonder he has 34 likes for 500+ posts.

Meh. Think what yall want. But spending this kind of money on rolling tubes without knowing whats actually going on in your amplifier is nothing short of flying blind. I care if you buy a western electirc, brimar, or hytron tube. I just care about using the right type of tube for the job.
 
Nov 29, 2019 at 4:02 PM Post #4,828 of 6,436
Nov 29, 2019 at 4:14 PM Post #4,829 of 6,436
Wish I could be there Capt D.

Hmmmm. I have a hankering for Fish planks and Hush Puppies all of a sudden. :smile:
 
Nov 29, 2019 at 4:14 PM Post #4,830 of 6,436
Meh. Think what yall want. But spending this kind of money on rolling tubes without knowing whats actually going on in your amplifier is nothing short of flying blind. I care if you buy a western electirc, brimar, or hytron tube. I just care about using the right type of tube for the job.
You care if we buy specific brands? I believe you mean you do not care. Good luck in your tube rolling or lack there of. :)
 

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