Let's talk about that blue gas...........

[Caper]

I have Jan Philips 6V6's in both my amps and both have been properly biased. Both sets of tubes are emitting a blue column of gas. One set is about a year old and the other set is new. I own a Hickok 6000A tester so I ran the battery of tests on the tubes and they passed. Filament continuity is good, gas test is good and tube life expectancy is good. Is this blue glow common to most tubes? Is gas necessarily a bad thing or what?

[boogaloo]

(might be a good name for an American tube company..)

Hi Caper-
I have JAN Phillips NOS 6L6's in my SFSR. They have the blue glow and they sound great; I'm told it's OK. Here's one link to this electrical phenom- I know there are others, I just can't find 'em now.

http://www.jacmusic.com/html/article...w/blueglow.htm

Hope this helps- I'm sure others will chime in. I think maybe Lord Valve has something on his site about this also.

Brian

[boogaloo]

http://www.kcanostubes.com/faq/blue_glow.html

Brian

"I gots 'da blue tubes baby sittin' by the San Francisco Ba-ay.."

[jjmantele]

I've used 2 sets of those and they both have the blue glow. I'm running an RCA now in my '74 Vibro Champ and it's blue too 8)

Blue is cool. Especially in the dark. Usually no problem.

[bgwatts]

My late 70's sfdr.has electro harmonix 6v6's and I ain't got no blue gas.Will it sound better if I add some gas?
I know that electricity works on blue smoke.'cause when you let the blue smoke out,it don't work no more.Maybe the same hold true for tone.
No,realy.I'm serious .The quest for the magic tube is an almost holy one.Is there soething going on with tubes that DO show the blue that is desirable?
The local amp dude set up my amp with a vintage 30 speaker(which I'm still not convinced was the best choice)and those electo-harmonix 6v6's.What do think?I hardly ever hear them mentioned here.The amp seems real strong.No,real compaints.But it seems like an unusual setup from what I read here.
Maybe something different is happening with the blue stuff that is BETTER?

[Caper]

My amp sounds great too, so I guess it really doesn't matter a whole lot. I have a Hickok 6000A tester and I just found out it can perform a test called a life test which can be used to determine how long the tube will perform satisfactorily. I am getting good readings from 4 power tubes that exhibit this glow.

[e-merlin]

If it sounds good it is good, doesn't matter how many people are holding their ears running for cover.

[stantheman]

when Ceasar Diaz came to The Hub he was totin' a Blackface Deluxe Reverb with a 12" Celestion V-30
and it sounded frikkin' amazing, he was also playing
a reverse Firebird w/ mini-hums. I know his tubes were
6V6's and he told us that the ONLY MOD to the Deluxe
was the Vintage 30. If my Jensen ever cooks that's
probably what I'll get for a replacement - it sounded
so good with that Firebird that any adjectives
wouldn't do it justice.

[bgwatts]

thanks for the story about ceasar's deluxe.Very comforting.
My apologies to all for hi-jacking the post.
But the blue gas question thing has me curious.
You just never know when you stumble onto some weird thing like "tubes that so show the blue sound better.I still would like to hear more from the tube guru's on that subject.Not the technical explanation of WHY the gas is present ,but if it actually affects the tone.

[Caper]

I still would like to hear more from the tube guru's on that subject.Not the technical explanation of WHY the gas is present ,but if it actually affects the tone.

One thing I did notice is that when I first put the tubes in there wasn't any gas. A few days later the gas was present, the sound remained unchanged.

[Teleologist]

Originally Posted by Caper

One thing I did notice is that when I first put the tubes in there wasn't any gas. A few days later the gas was present, the sound remained unchanged.

Many NOS USA tubes glow because of impurities in the glass. I have a pile of the Phillips/Sylvania JAN 6V6GTs and most of mine do but I've known about this for a long time and I'm usually looking at them for signs of orange spots on the plates. If you look at the plain side of the plate, you'll see a little trap door like exhaust opening and you'll usually see glow on that side where stray electrons escape and hit the glass. The amount of glow could depend on how open this port is. Other places electrons can escape would be from the plate seam on the other side and any gaps between the plate structure and spacers.

This all has nothing to do with tube age - Dual Showmans & Twin Reverbs with original RCA or Sylvania 6L6GC's did the blue glow dance back in the 60s - Turn off the lights, turn up the amp, and watch the tubes while you play ;)

[reverbbb]

Last Sunday night, my friend was letting me play his Marshall JCM 2000. All of a sudden, the was a BIG blue flash on the wall behind the amp. Then no more sound.

It sort of reminded me of the time I ran the speaker output of a 50W Marshall into the guitar input of a 100W Marshall. Recomendation: DON'T TRY THAT ON YOUR AMP! What can I say? I was very young and just as crazy then as I am now.