• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join freeLog in
    Want zero display ads or expanded classifieds tools? Compare plans.

Touching your tube is bad. Right?

I had a bit of a debate with a guitar buddy.

I told him that after you change or touch a tube, you should wipe it clean with isopropyl alcohol.

He fiddles with his tubes constantly, and he says he has never had a problem. Changing them in and out and buying "vintage" tubes that sound the same to me.

The advice I was given in 1978 has stuck with me: "If you get oil from your skin on the tube, it can create a 'hot spot' that can affect performance or even destroy the tube"

Is this true?
 
I had a bit of a debate with a guitar buddy.

I told him that after you change or touch a tube, you should wipe it clean with isopropyl alcohol.

He fiddles with his tubes constantly, and he says he has never had a problem. Changing them in and out and buying "vintage" tubes that sound the same to me.

The advice I was given in 1978 has stuck with me: "If you get oil from your skin on the tube, it can create a 'hot spot' that can affect performance or even destroy the tube"

Is this true?

I don't think the glass enclosure gets hot enough for there to be any damage caused by the oil on your fingertips (I can't see a few microns of oil giving a massive insulating effect), though I have heard the same advice for halogen light bulbs, that the uneven heating can cause the glass to crack.
 
Hi.

Actually, the Halogen bulbs don't explode afterwards if You touch 'em with Your bare fingers, but the oily residue that's left there and get burned to the surface will affect the amount of light that passes through the glass.

I've tried that in the past, confirmed it's true, and always avoid touching the bulb.

If You read in the light of the tubes in Your amp, it could well be a problem, otherwise IME no.

Regards
Sam
 
  • Like
Reactions: downlowuponit
Better to touch the glass than the Pins. Pins are actually conducting power, not radiating heat.

From Justin Holtons site
" "I heard you should not touch your tubes at all (even when they're cool)."

My dad even told me this one! I've read that the oil from your hands will build up on the tube causing it to run hotter than it should. Yeah, right. 1. In combo amps most of the heat goes up into the base of the tube, rather than out the side of the glass. 2. A minute bit of oil from your hand is NOT going to affect the tube's reliability/performance. Manufacturers print their logo on them don't they? Does that cause heat dissipation problems? Come on, I think cramming the tube up inside a metal chassis has more affect on heat dissipation than your fingerprint. Please, do not worry yourself over something as silly as this. You should, on the other hand, refrain from touching the tube's pins a lot. If you do accidently touch the pins there's a 99.99% chance that nothing will happen, but if you're having some weird problems cleaning the pins will sometimes solve them. Occasionally, after moving your amp to a gig or practice, you should make sure the tubes haven't shaken loose. Just give them a little push upwards from the bottom with, you guessed it, your hand."

Invalid Link Removed
 
Dirty tubes smell funny when they get hot. That's about it. They are made of glass, glass is famously inert, which is why you can store chemicals in them without them dissolving, and food in them without it tasting of glass. As for carbon deposits upsetting them, those fancy hifi tubes that are black inside? Guess what the black is.