Flex2, yes, but I have to pick one 🙂 I’m a bit OCD I’m afraid. Have a few days until they arrive, so got time to think about it.
Zung, it could probably use a fan for cooling, but I just can’t deal with fans in audio equipment … I always hear them, even quiet ones.
grataku, just replaced with the Dale Resistors … just looked more robust and reliable. Hadn’t seen your post until just now so I’m glad you concur 🙂 Pics …
It biased up just fine … nice to see the tubes glowing again! Haven’t played anything yet , will try tomorrow, got to get some rest.
The VT130 makes music again , sounds really good! Going to replace the resistors in right channel now and buy a matched set of TungSol 6550 tubes to replace the left channel ones. They really are great sounding tubes in this amp. Just as long as they don’t die, huh
I use JJ tubes for the gain and driver stage tubes, which I also really like for this amp.
I use JJ tubes for the gain and driver stage tubes, which I also really like for this amp.
I replaced the older tubes with a set of new TungSol tubes, in the left channel. Everything was fine so I put the JJ 6922 gain and driver tubes which were in the left channel when the resistor blew.
Then I heard a couple decent pops after turn on in the left channel, and I turned the amp off.
So I put the old 6922 and 12BH7A tubes in and again heard a couple soft pops as the amp warmed up … looking at the schematic I don’t see that gain or driver tubes could cause damage to the output tubes? Or is that wrong?
I’d like to at least use the JJ 6922 tubes as they are almost new. But I’m worried about trying them again. Any concern here?
I hope I didn’t damage any of the new output tubes by putting the JJs back in.
Only get very soft pop sometimes after turn on, during warmup … but my experience is that things can get go downhill over time.
Then I heard a couple decent pops after turn on in the left channel, and I turned the amp off.
So I put the old 6922 and 12BH7A tubes in and again heard a couple soft pops as the amp warmed up … looking at the schematic I don’t see that gain or driver tubes could cause damage to the output tubes? Or is that wrong?
I’d like to at least use the JJ 6922 tubes as they are almost new. But I’m worried about trying them again. Any concern here?
I hope I didn’t damage any of the new output tubes by putting the JJs back in.
Only get very soft pop sometimes after turn on, during warmup … but my experience is that things can get go downhill over time.
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no more pops now … hoping just a break in of new tubes. Getting new set of voltage gain and driver tubes for the left channel to be safe.
Tubes sometimes makes sound of their own when just turned on and should be silent when warm.
If they start making crackling and other sound when fully warmed up you should look into why.
Output tubes near end of life occasionally makes some crackling noise and pops even fully warmed up.
Make sure you buy 12BH7 that have matched halves.
One of them are involved in the bias circuit and benefits from equal performance.
If they start making crackling and other sound when fully warmed up you should look into why.
Output tubes near end of life occasionally makes some crackling noise and pops even fully warmed up.
Make sure you buy 12BH7 that have matched halves.
One of them are involved in the bias circuit and benefits from equal performance.