ok I Bought it ... what now :D

[Grog]

i've only noticed it on the left so i'll check and swap them over.
it'd be a shame if they are old/worn out, i think i have a couple of ecc82's with about 10 hours on them, different makes one is billington own brand (i think)
i could try this just to prove the point.

there is a blue corona glow from the KT88's (these are new acording to hugo) it's kinda projected through the holes in the anode, but it's permanent and i think normal?

[Richard]

Yes some blue glow is normal, inside the plates and dancing a little on the edges and the glass. The bad stuff is purple and the valve and voltages will tell you about it. If you're back into valves you'll find known good spares useful to compare for wear and to use as replacements as needed.

Rich

[Grog]

the glow is not purple, just a light blue flicker inbetween the plates and glass.
i'll try and get a video of it on my phone tonight, it looks pretty if it doesn't mean anything bad i quite like it.
i'll also try the other ecc82 i have and see if that does it too.

[Hugo1]

George

I'm glad you're having some fun with the amp. The best small tubes that I ever tried with it were RCA 6AU6; and the Telefunkens aside, Radio Technique ECC82 which Watford Valves still sell for £15 each. That was with JJ KT88s, though, which are in my view rather more punchy and lively than the Electro Harmonix ones. That's probably why those EH tubes never had more than a few dozen hours on them. I would definitely try alternative power tubes - some rate 6550C, particularly the Svetlana, and you have the necessary components in the box to alter the dissipation to suit those valves. Richard will no doubt clarify what needs to be done if you are tempted to go in that direction.

Regards etc

Hugo

[Grog]

hi Hugo,
thanks, i'm having much fun with it, really glad i bought it.
don't suppose you know how much use the telefunken ecc82's have had, i guess they are nearly due for replacement, but i don't want to take them out if they are nearly new!

i've put the upgraded heater BR in with a CRCRC filter, havn't got round to putting in the upgraded bias bridge i found in the box of bits, did this make much difference?

[Grog]

I can't seem to get a video/photo of the blue flash, light's all wrong for my naff camera phone!

i swapped valves and the flash seemed to follow the valve, although the other channel does it slightly just where the bottom mica is.

I hope santa knows where to get good ECC82's

Originally Posted by Grog

the glow is not purple, just a light blue flicker inbetween the plates and glass.
i'll try and get a video of it on my phone tonight, it looks pretty if it doesn't mean anything bad i quite like it.
i'll also try the other ecc82 i have and see if that does it too.

[Hugo1]

Originally Posted by Grog

hi Hugo,
thanks, i'm having much fun with it, really glad i bought it.
don't suppose you know how much use the telefunken ecc82's have had, i guess they are nearly due for replacement, but i don't want to take them out if they are nearly new!

Those Telefunkens were quite old, and very well used. I would definitely experiment with other ECC82s - the Radio Technique Mil spec ones are quite superb and a good starting point. The only duffer that I tried was the new JJ ECC82, which was as dull as dull can be. Quite odd given the superb performance of the JJ KT88.

Originally Posted by Grog

i've put the upgraded heater BR in with a CRCRC filter, havn't got round to putting in the upgraded bias bridge i found in the box of bits, did this make much difference?

I cannot remember, to be honest. For most of its life with me, the amp ran with bespoke Paul Hynes Design regulators, including the heater feeds to the small tubes.

Cheers

Hugo

[Grog]

are these worth a go? or could i do better for the money? the RFT at £8 (langrex) is tempting as it's not a lot of money.

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=220315577454

[Richard]

Check post 30 George, 5814 work fine, somewhat dark sounding, and on the Langrex page for £5 each, the RFT are pretty much the aural opposite...