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  #11  
Old 6th January 2011, 07:26 PM
John Caswell John Caswell is offline
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Default Re: WD88va no output on one channel

Hi Mark,
Well the ECC803 is reckoned to be an updated ECC83 so that should be fine but if you want to be pedantic thean look for a Mullard/Philips ECC83, or a Brimar/American 12AX7, a Marconi/EMI/GEC B339 or even a Mullard/Phiips Special Quality valve M8137/CV4004, but be prepared to dig deep. You could also try a 5751 but the gain will be a little lower.
Personally I don't rate cryo'd valves but there are those that do, it is up to you.
Don't be seduced by people saying the CV*** valve is a special military version. "CV" means "Common Valve" and was introduced in the war as the three services had a lot of identical valves but with different names/numbers so to simplify purchasing/stock etc the CV nomenclature was introduced.

John
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  #12  
Old 6th January 2011, 07:48 PM
Richard Richard is offline
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Default Re: WD88va no output on one channel

Quote:
Originally Posted by Mark Keller View Post
Hi,


Also any idea what may have cooked it, I am driving the input from an Apogee Duet and have the output on max, it has unbalanced -10 dBV line outputs, will this set the level too high and overdrive the input of the WD88VA damaging the input valve?

M.
That's good Mark, the ECC803 should be fine or any of the others as John says. If the original was a JJ red print ECC83S with short box plates they are unreliable ime. EI ECC83 are very full and lively sounding. GE5751 have great soulful tone

So probably just bad luck. It won't have been overdriven. The vol pot is before the first valve and the amp gain ratio is fixed after the first valve. Therefore you'd hear the whole amp being overdriven if the first valve was being overdriven.
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  #13  
Old 7th January 2011, 09:20 AM
Mark Keller Mark Keller is offline
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Default Re: WD88va no output on one channel

Thanks very much for the info guys, the original was indeed a JJ red print ecc83s with I guess the short plates, as the guy I bought the 803 (again a JJ red print) from said that the main difference on the 803 was that it had longer plates and was a better valve.

So problem solved, looks like I might start experimenting with different valves!!

Thank you both again for all your help.

Best,

M.

PS the Gold Lion KT88's seem really nice and detailed from the little I've heard so far.
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  #14  
Old 7th January 2011, 10:30 AM
Richard Richard is offline
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Default Re: WD88va no output on one channel

Hi Mark,

Yes I like the Gold Lions a lot, I hear them similar to you, some comment here,
http://www.world-designs.co.uk/forum...ight=gold+lion

You can obviously hear the differences valves can make and as you only need 1 x ECC83 (type) you should have a bit of fun trying a few to get the sound you like! Go for new current or boxed nos (new old stock) and beware unboxed if you can't test/get them tested.

The red print JJ comment wasn't telepathic btw, just that I know WD used to supply that valve and have exp of it myself.
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  #15  
Old 7th January 2011, 11:26 AM
Mark Keller Mark Keller is offline
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Default Re: WD88va no output on one channel

Excellent,

Thanks Richard.

M.
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