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6v6 Tube blue gas show

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7/26/2000 8:25 PM

6v6 Tube blue gas show

I am curious if it is any problem with this
I have a home built amp with 2x6v6 cathode biased 350v the plates, 330ohm cathode resistor and it runs around 35ma trough them,
however when I play it the tubes having a blue light show pulsating back and forth, the funny thing is these tubes show no blue light when I put them in my BFDR with "normal" bias.
should I worry? It sound OK and the tubes are NOS. RCA .
JD

7/26/2000 9:02 PM
dave	Just enjoy it!

7/26/2000 11:39 PM
Tim C.	Some of the best sounding amps I have ever played did the "Blue Gas Show". The harder you push the amp the more they show. Tim C.

7/27/2000 12:11 AM
J D	Thanks guys ! Yeaa, the amp sounds really fantastic, I just wanted to be sure that nothing was wrong , I appreciate your help! JD

7/27/2000 5:54 PM

The blue glow just means that there are a few stray gas molecules flying round inside, it's very difficult to get a complete vaccuum, but its close enough not to affect the working of the tubes. This effect is explained by quantum physics (Sounds good, "I've got quantum physics in my tube amp") and I can give the scientific explaination of exactly what happens if anyone is interested who hasn't come accross it.

Chris

7/28/2000 2:07 AM
Tim C.	Chris, I would be interested in hearing your scientific explanation. Thanks, Tim C.

7/28/2000 6:19 PM

Here comes the physics. I shall assume you know some basic principles, if not I'll simplify it further. Ignore the bits in brackets to start with.

You are probably aware there are a lot of electrons flying around inside tubes, accelerated to a fairly high speed by the plate-cathode voltage. Some of these electrons will collide with the stray atoms, and may cause the atom to gain energy, (an electron in the shells will be moved to a higher orbit) when the atom releases this energy, it does so in the form of light (the electron displaced or another returns to its orginal lower energy postion, and a photon is released). There are fairly simple calulations that con be done to find out the energy of the electrons etc.

Hope you can understand that, and could someone please proof read it and make sure it is accurate.

Chris

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