If this is a silly question, sorry. I’ve never owned tube equipment before. When handling halogen light bulbs, popular wisdom says never touch the bulb with your fingers. They claim residual finger oil left behind will form a hot spot, causing the bulb to burn through, causing a failure. I find it hard to believe the tubes in an M1200 amp would run that hot but thought I’d ask anyway. Do you need to take such precautions with audio tubes? I ordered a replacement set to try to see if it was time to retube or if the originals could run for a bit.
Yes, it’s best not to have finger oils on your tubes. I wear white technician’s gloves that are anti static to grip and handle tubes.
Thanks, I’m glad I asked.
Halogen bulbs should not be exposed to oils. but audio tubes are robust critters you will not harm by touching them. Aesthetically I do not like fingerprints on tubes so I use a cloth to install and remove.
Remember, tubes were used in all sorts of TVs, radios, etc. for years. When a tube failed with use, the consumer went to the store, tested the tube on the tube tester to see if it indeed failed, purchased a new tube and installed it - all with bare hands. Just like replacing an incandescent bulb.
Be careful with the logos on vintage tubes however. It is easy for them to rub off.
I remember those tube testing stations in stores. Boy, have times changed.
I’ve never (in maybe 40 years of tubes) had a problem. Except one time I touched a hot tube. That was a problem.
Just keep your hands clean–like your mother told you—and you won’t have a problem.
One bit of advice i would give a newbie is to remove tubes that have a base by the base, not the glass.
And the gloves are a good tip although I find them slippery.
Good advice as to the base.
I ordered replacements for my M1200s from PSA, with the tube puller. We’ll see. There were many other good tips from fellow forum members about looking in through the side vents went making the change. This really is a helpful community of people.
I too wear white gloves when handling tubes. Not because I worry about creating a hot spot, but because I don’t want my paw prints on my precious glass when I admire it on and glowing. Yeah, that’s a pride of ownership thing.
What you really need to be worried about is the impact your discretionary income as you go down the tube rolling rabbit hole. Consider yourself warned.
Btw I also have a bit of advice on useful tube accessories. I own a pin straightener:
Best money I’ve ever spent for tube maintenance. Makes getting a small signal tube into its socket with minimum stress on the socket and circuit board a snap.
I wouldn’t worry about it. The only thing you have to worry about is if the tube is too hot. It only takes a few minutes for a tube to cool down. Any labeling on the glass is also vulnerable. But otherwise tubes are pretty tough. The glass is a lot heavier than a light bulb. The only time I worry about fingerprints is if I’m trying to sell them.
Tubes are pretty rugged. Once in a great while you’ll get a flakey tube. A little body oil wont hurt them. Depending on the equipment configuration, socket saver risers can help cool them if they are recessed in the case (Schiit MJ2).