6H30 tube life
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Thinking of getting an Audio Research LS-26. They have 6H30 tubes and I was told they only last about 800 hrs. Is this true? I thought they were good for up to 5000 hrs. I need some clarification as these tubes can be expensive.
I can only relate my experience in another company's amplifiers. The new cj ART uses the 6H30 tubes in the driver stage and after getting the amp, I went through two (of four) 6H30s in a matter of only six months. The tubes were start to crackle, then sound staticky and finally start glowing a beautiful fluorescent lavender
(Very unusual, never seen anything like that before!) Luckily now, I seem to have been trouble free for over a year and a half now. I also tried the "supertubes" like BAT (or some other tube vendors) sell and didn't think them worth the money--at least in the cj amplifier.
The 6H30s in my BAT VK32 SE are going strong after 6 years. The pre has been in continuous use in my HT with a VK-6200 for 3 years.
I can only relate my experience in another company's amplifiers. The new cj ART uses the 6H30 tubes in the driver stage and after getting the amp, I went through two (of four) 6H30s in a matter of only six months. The tubes were start to crackle, then sound staticky and finally start glowing a beautiful fluorescent lavender
I also tried the "supertubes" like BAT (or some other tube vendors) sell and didn't think them worth the money--at least in the cj amplifier.
Hey Myles, how long have your 6922 tubes lasted in your CJ GAT? I have changed tubes 2x in 3 years. One channel or the other becomes crackly...in the end, I ended up taking the 2 non-crackly tubes from two different prior sets (which I tend to keep as backup)...and putting one from each set back in...now enjoying total silence. But not sure how long they may last.
Have to say haven't had an issue though suspect it might also be due to how many hours many hours do you listen per week and how long did they last before going noisy. My original were going strong for 2 years and replaced them just because thought they should be replaced; didn't notice much of a different however
The new tubes have been performing adequately now for six months with none of the issues you seem to be experiencing Tell you, sometimes think tubes are worth it anymore given the hassles with getting good sounding ones esp. ECC83s
Have to say haven't had an issue though suspect it might also be due to how many hours many hours do you listen per week and how long did they last before going noisy. My original were going strong for 2 years and replaced them just because thought they should be replaced; didn't notice much of a different however
Tell you, sometimes think tubes are worth it anymore given the hassles with getting good sounding ones esp. ECC83s
Thanks...may have bought some so so tubes...though I have to admit, each pair did have 1 tube which has gone a year and remains perfectly quiet...the other 2 perhaps were 'duds'. I probably get about 2000 hours/year on the system.
I only replaced the 10 6H30 of my Audio Research REF 40 at around 6000 hours. They still measure like new, but as one or two of them started emitting strange low level crackling noises intermittently - a few minutes or seconds now and then - I decided to replace all of them.
IMHO, getting 2000 hours from a russian tube is about what one can expect. We're not talking bout tubes made in the '60s
What tester do you use to measure your 6H30s since they're a relatively new tube?
It is curious though that a tube test good with something like the George Kaye tester yet is clearly shot eg. the dynamic and upper octaves are going, going, gone.
IMHO, getting 2000 hours from a russian tube is about what one can expect. We're not talking bout tubes made in the '60s
These are either amperex us pq white label 6922 or mullard 6922s...how long should those last? I thought closer to 5000?
Lasting is one thing. Did that ever, though, have any application to audio applications? Sure the tube will light up but how long will it stay noise free or even sound good for audio applications?
Tubes can still measure like new in terms of emission, but yet be noisy. I'm sure we all have experienced brand new tubes straight from the box being microphonic and/or noisy. The cathode's job is to emit electrons (and enough of them to sustain the rated curent) and have them travel through the grid(s) to the plate (anode). When a tube is nearing end of life, it can no longer emit enough electrons from the cathode to sustain the correct cathode current. The electron stream is just too weak. That's why the better tube testers actually tested the cathode emission to see how strong the cathode is. Some of the better testers (think Hickok 539C) had a cathode life test where it would reduce the voltage to the cathode and measure how much the emission dropped.
And having said all of that, the 6H30 has supposedly been rated at 10,000 hours of life. If you increase the heater voltage above the rated spec, you will greatly diminish the cathode life. I have said this numerous times before, in a perfect tube world, all tubes would die a natural death of cathode depletion (they just can't emit enough electrons anymore). In our in-perfect world, tubes die for other reasons (cathode to grid shorts, cathode to anode shorts) or they just become unusable due to microphonics/noise. You have lots of metal parts inside a tube with different coefficients of expansion. Sometimes parts become loose and start rattling around.
And having said all of that, the 6H30 has supposedly been rated at 10,000 hours of life. If you increase the heater voltage above the rated spec, you will greatly diminish the cathode life. I have said this numerous times before, in a perfect tube world, all tubes would die a natural death of cathode depletion (they just can't emit enough electrons anymore). In our in-perfect world, tubes die for other reasons (cathode to grid shorts, cathode to anode shorts) or they just become unusable due to microphonics/noise. You have lots of metal parts inside a tube with different coefficients of expansion. Sometimes parts become loose and start rattling around.
True...I suppose I was hoping if a tube life was rated for 10,000 hours, one could hope for at least half that to be nearly noise/crackle free.
From what I've read, one of the big problems is the coating on the filaments of the Russian tubes that leads to them becoming noisy.
Myles,
I use an Amplitrex and Tek 576 Curve Tracer. I'm very enamored of the CT.
Myles,
I use an Amplitrex and Tek 576 Curve Tracer. I'm very enamored of the CT.
I bet you are as the 576 is a very useful tool to actually match output tubes.
Hi Mark,
The 576 is my favorite
But you can't test a 6H30 on it can you? It's not a 6DJ8 family so assume you use the Amplitrex.
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