bloody valve amps blowing up again

bottleneck

talks a load of rubbish
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they are.

again.

if someone took my pre/power off me now and swapped it for an accuphase integrated or a solid state MAC, I'd shake them by the hand..
 
oh its not blowing up, its just a valve which is about to go pop.

I'm getting sick of valve amps, I want reliability and consistancy.. I think I want solid state.

My power amp is a Conrad Johnson Premier 11a, and the Pre is a Consonance Basie (modified).
 
How often do you get through valves then? I wouldn't have thought the main reason for anyone to change would be reliability, don't valves last at least 8 months?

Edited to add, have a look at the JungSon JA-88D.
 
Jungson JA-88D... heard one a few months ago....very nice but huge. Can be had for £450 ish on ebay too.
 
bottleneck said:
oh its not blowing up, its just a valve which is about to go pop.

I'm getting sick of valve amps, I want reliability and consistancy.. I think I want solid state.

My power amp is a Conrad Johnson Premier 11a, and the Pre is a Consonance Basie (modified).

Chris, what valve is it?

The only problems I've had with blown tubes is with 5U4 rectifiers, but that's partly because my amp stresses them too much due do a small oversight on the part of the designer ;) - which is about to be sorted.
 
Oh dear, sorry to hear it Chris. The main reason I steer clear of 300B World and stay in 6B4G land but it sounds as if you've been having a few concerns as I'm sure one valve every year or two would not stress you out.
 
If they are not lasting then they are being overdriven.

My KT88's of the power stage should last in excess of 2000 hours.
I swapped out the Svetlana's after 2.5 years not because of reliability or any problems but I fancied a set of Tesla's.
The driver 6SN7's are probably good for over 6000 hours.

It's silly if the manufacturers are chasing watts and shortening vavle life.
8 months with an average of a couple of hours use everyday sounds like a fault to me.

What Valves are you buying?

Any way transistors suck - as one website out it
 
Keep the faith, Chris. Don't make any sudden moves.

What you really need is to live with an S/S amp for a couple of weeks while your valve amp is 'off the road'. That would have you craving that old glass magic again.

Cheers
Steve
 
Chris,

are those the original tubes that were in the amp when you bought it s/h?

If so, well...Like a ferrari needs more regular servicing than a VW, so the best amps have running costs. Just keep a spare set of tubes at home - they aren't overly expensive unlike your previous amp.

Of course McIntosh claim around 5K hours for their tubes, Berning more. But I look forward to your thread claiming you are fed up with vinyl (because damned needles keep going) and are switching to crappy disc.
 
Make your own. get the dissipation right, you won't have any problems. Plenty of good circuits on the web. I do agree with you though Paul. The 6B4G is a lovely valve. Made a 3W SE for a friend and it sounds far too nice. 5687 SRPP driver much better than expected. Might have to make another for personal use!
 
Decent valve amps fitted with good quality valves shouldnt cause problems. The valves in my Audio Research amp are coming up to 2 years old with not a hint of trouble.

Perhaps try a different brand of valve with a good reputation for reliability e.g Svetlanas?
 
sounds like you are running the valves too hot, try changing the value of the cathode bias resistors.
your valves aren't ei elites by any chance ??
I would say 1 year for power tubes and 2 for pre amp tubes before they sound muddy but won't normally fail for a while after that.
 
Chris, are you talking bout a valve in your power amp? Some kinds of valve are more reliable that others.

Is it always the same position in your power amp that gives you trouble? Then something may be wrong there and needs to be seen to.

Are you sure your modified pre is working well? Sometimes, oscillation in the pre can cause problems in the power amp.
 
Hi Chris,

Sorry to hear about your valve trouble. Which amp has the trouble with the valve? Pre or power? How often has it happened?

I must admit to not having many problems with my amps. If operated with in it's performance envelope, a number of valves will last a long time. For example, WE 300B has a life expectancy of 40000 hours. Having used some, I can say this claim is more or less true.

Maybe your amps need checking.

SCIDB
 
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