The general rule of thumb is don't get body oil onto the tubes. I've always been able to get a hold of my tubes at the base and gently pull or rock them out.
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I too try to avoid direct finger contact with the glass of the tube. Generally I use a paper towel folded and wrapped around the tube and grip at the base...but my tubes are pretty much fully exposed. I like the cotton sock approach. Am using one to protect my safety glasses from scratches when I have to travel!
Being that they only stick out about 3/4 of an inch as you said, try what the other guys said. Do not use anything adhesive as the adhesive may leave a residue on the glass. Do not use a pliers or anything like that due to not being able to feel how tight it really is which can so easily lead to crushing the tube in a split second or cause a microscopic crack which will leak air into it, overload the air or oxygen capability of the getter to absorb it, and destroy the tube in time; be it soon or long down the road. I had KT88 power tubes go that way. They lit up from the inside, burned a beautiful pastle like pink and purple for about 20 seconds, and then died. After a week or so though, they got all powdery white inside as the getter got swamped and could not absorb any more air. As for other tubes used in that brand and model of gear, I had a pair of NOS Mullard 12AU7's and they were as wonderful sounding in all ways as the legends of them describe accurately. JJ makes great sounding 12AU7's as does EH and Ruby. Same for the 12AX7's. It is personal preference, honestly. It can be a massive difference or a subtle and need to listen for it change. They at least tend to be inexpensive unlike power tubes.
I asked Roger Modjeski (Ram Labs, Music Reference) about this, and he said the idea that you should not use your hands is a myth, he then explained to me why, but I don't remember his rational).
It's called audiophile paranoia. Seriously, what possible harm could come from getting bodily oils on the outside of a GLASS tube? I suppose that constant handling of the pins could cause them to tarnish a bit, but most are tarnished anyway, especially on NOS tubes. Just make sure the tube is cool, use your hand and pull it out. Wipe it off afterward if you don't like the fingerprints.
I've always believed the myth came from other types of bulbs that get very hot. In a previous job I dealt with 1000w bulbs and the word there was don't touch. We always had latex gloves on (clean room) and we were told to put a clean pair on before we touched those bulbs. But those bulbs got many times hotter than a power output tube.
Do you put gloves on to change a light bulb? Ever had one crack?
Quartz Halogen, and some Metal Halide bulbs, will immediately go bad, if any kind of residue is left on their envelope(they get that hot). Personally, I just don't want anything leaving, or collecting, funk on the glass or bases of my tubes, or anyone else's that I service. I'm not worried about them going bad.
I realize that it's best to be careful with your tubes but if you are talking about old stock, they can be 50, 60, 70 years old, probably previously used, and for most of their life considered worthless. They have probably been handled, tossed, shaken, thrown in a drawer or box, stored in a basement and who knows what else.
I've always believed the myth came from other types of bulbs that get very hot. In a previous job I dealt with 1000w bulbs and the word there was don't touch."
That was precisely the reason Roger Modjeski gave for the tube/fingers myth. Now, I did not ask him about using a good quality moisturizer for improving midrange bloom - I'm going to check his webiste to see he makes any mention of it.
You need one of my cryogenically treated,1500 thread count,egyptian cotton tube gloves.The better models use 14K gold thread.I have some in minty condition(with 14K gold thread) that I'll let go for $1795.00 plus shipping.Please specify left or right,better yet,buy both so you can switch change hands and save on wear and tear.Always demagnetize the glove before using(I also have demagnetizers for $229.00,free shipping if you buy a glove).Treat your tubes right,don't settle for anything less.Don't listen to the quacks that were talking about the moisturizer,I tried it,it's a total farce.You need to stick to sound,scientifically proven ideas(like my tube gloves).Happy listening.
Which moisturizers have you tried, and with which tubes? You can't disregard synergy. Various tube types respond differently to different moisturizers.
How much moisturizer did you use? The general rule is to use about half as much for "new old stock".
Were you precise in timing the conditioning? Too much time can result in a loss of base extension; too little time and you get rolled off highs.
Farce?! Don't even get me started on manicures.
While there is no harm in keep oils from your hand off of the tube, it is hardly necessary. The tubes do not suffer from the same failure mode as halogen, metal halide, etc. bulbs.
When oils from your hand get on the bulb, the high temperature carbonizes the oils and this forms a dark spot on the bulb. That dark spot will then absorb light from the bulb, instead of passing the light through, which heats that particular spot more than the rest of the bulb. That temperature differential causes the bulb to explode. Your tubes never get hot enough, nor do they put out the huge amounts of energy that could cause that kind of hot spotting from what is on the glass.
Don,there are no myths in audiophiledom,only hard scientific facts.If you read something here you can take it as a gospel fact.I am sure no one will try to steer you wrong on these forums,except those nuts above trying to push the hand lotion notion,what a crock of crap.BTW,I am running a Christmas special on my Tube Glove/Demagnetizer combo.Only $1500 for both with free shipping.In the words of the great Pete Townshend...I call that a bargain,the best I ever had.Have a nice day.
If you worry, wipe down with some Iso alcohol after install. don't drip or soak it. damp lint free cloth will be ok. Handle with latex or vinyl clean-room style gloves. Make sure any vapors have evaporated before starting equipment.
Finger oils are generally bad for thin glass envelops, hotter=worser.
I've changed hundreds of hi pressure mercury vapor lamps in semiconductor processing equipment by this means.
Worrying about how to remove the tubes seems kind of silly after seeing how they are made and packed :)
That said either use cotton gloves or some cat grooming gloves with little rubber dots. If nothing else, want to be careful not removing the logo from the tube.
As explained above, there is no operational reason for worrying about handling tubes. My only possible concern would be the easy to rub off markings on extremely rare Telefunken tubes. When my ECC803S tubes are near the end of their life, how will I be able to sell them on ebay as brand new if I am not careful about rubbing off the markings on the tube?
Jea48. I pulled them and the preamp 12au7 is a Sylvania. Out of the other two 12au7's, only one of them I could read '12au7'. I got nothing off of the 12ax7's. I think they're probably all Sylvanias. I think I'll shoot Mark O'Brien from Rogue and e-mail and ask him.
I'm considering rolling the 12ax7's. Not because I'm unhappy with the sound, but because I've never tube rolled and would like to hear the differences for myself, as opposed to reading other peoples description of the differences.
Amperex (Bugle Boy) and Telefunken work great in other preamps I have.Make sure if you get Amperex,get the Made in Holland labeled.Since Richardson bought their name,there are all kinds of budget Chinese (plus who knows where) made Amperex tubes out there.Nos RCA's are ok,but may not perform better than the Sylvania's that you have.They're good tubes too.A link may help some.♫Link>>[http://www.guitaramplifierblueprinting.com/tube_makers.html]