1. Win a Broadcaster or one of 3 Teles! The annual Supporting Member Giveaway is on. To enter Click Here. To see all the prizes and full details Click Here. To view the thread about the giveaway Click Here.

Tube dampeners

Discussion in 'Amp Central Station' started by IowaCorn, Mar 9, 2014.

  1. IowaCorn

    IowaCorn Tele-Meister

    Posts:
    151
    Joined:
    Sep 10, 2013
    Location:
    Midwest
    Can any of you fine people shoot me in the right direction as to where I can find affordable yet durable/effective tube dampening rings? A little rattle going on with the 6V6 power tubes. Thanks for any advice ladies and gents!
     
  2. backline

    backline Tele-Afflicted

    Posts:
    1,522
    Joined:
    Oct 6, 2008
    Location:
    USA, CA, 94585
    You can really use just about anything that will take the heat...you could use rubber bands if they would not melt.
    But if you punch those two words into your computer, you will get several commercial offerings to choose from.
    good luck
     
  3. vanr

    vanr Tele-Afflicted

    Posts:
    1,218
    Joined:
    Oct 20, 2003
    Location:
    AZ
    You can get high-temp silicone o-rings at the hardware store. Just take some tubes along to get the proper size.
     
  4. 1955

    1955 Doctor of Teleocity

    Posts:
    10,372
    Joined:
    Apr 10, 2010
    Location:
    .
    Auto parts store - heat resistant silicone. They dry out eventually. You can put one at the top of the tube where it goes in the socket, and 2 or 3 on the tube itself. They stink and smell burnt at first, don't worry about it, just monitor it at first to make sure yours are the high temp silicone.

    I made a faux Tom's Tube Tamer out of a small curtain rod, the empty rings of electrical-tape, removed the spring from the rod, got it to the right width, taped it good so it was tight against cab, and used little corner supports to press it up and lock it up good and snug against my chassis. (Discharge caps when going inside amp.) Don't even touch anything until you know how to safely work in there!

    image-281198582.jpg

    Don't forget, a rattle can be anything from unused tube socket pins, (had to bend them back with pliers) components/screws/hardware in chassis, chassis itself if not flush against top of cab, (cotton swab to stop back panel flapping) etc., or all the above.

    The rings dampen some, but pushing and locking those tubes up into the socket and using corner supports with foam cushioning between the chassis and cab to lock it in, wood-gluing the baffle edges did the trick for me. You have to unscrew the corner supports to change a power tube or rectifier, but that's so rare it's worth it.

    The reverb tank at the bottom is encased in foam, wrapped with a dish towel, and taped, so it doesn't crash as bad.

    I also took the metal tube protectors off the tubes, because they were a real ringy-dingy nuisance.

    Tube sockets also can be tightened. (Have to know how to safely do this!)


    Foam between chassis and cab also, and foam in cracks of baffle where it seams to cab, then wood glue on top of that.

    Sitting on the amp can tame certain rattles, so if that's the case, check the handle. Just putting something under the handle can cause a rattle to soften up!

    Jewel pilot lights, pot nuts, input jacks, screws etc. get loose over time.

    Very few people have done this to this degree as tar as I know, but I have really benefited by it!
     
  5. SPUDCASTER

    SPUDCASTER Poster Extraordinaire Gold Supporter

    Posts:
    9,509
    Joined:
    Sep 7, 2010
    Location:
    Grangeville, Idaho
  6. ASC67

    ASC67 Friend of Leo's

    Posts:
    4,315
    Joined:
    Jul 3, 2008
    Location:
    Minneapolis, MN.
  7. andyfromdenver

    andyfromdenver Friend of Leo's

    Posts:
    4,703
    Joined:
    Dec 21, 2011
    Location:
    grandpa's
    Good post 1955! Thanks!
    Very DIY :)

    I want those foam things fender put in the Hotrod deluxe or whichever that is.
     
  8. gitapik

    gitapik Tele-Afflicted Gold Supporter

    Posts:
    1,052
    Joined:
    Jan 16, 2010
    Location:
    New York City
    +1

    I had the store-bought "O" rings on for a while and they were pretty good. The Eurotubes dampeners are better.
     
  9. CoolBlueGlow

    CoolBlueGlow Tele-Afflicted

    Posts:
    1,536
    Joined:
    Nov 20, 2011
    Location:
    Arkansas
    Remember that radiant cooling of the tube envelope is the primary means whereby the plates dissipate heat out of the tube. As you find innovative ways to damp the tube, it is therefore always wise to consider how such damping might affect dissipation. Adequate heat dissipation from the glass envelope is vital to tube life.
     
  10. gitapik

    gitapik Tele-Afflicted Gold Supporter

    Posts:
    1,052
    Joined:
    Jan 16, 2010
    Location:
    New York City
    Hmm....hadn't thought of that. The Eurotubes are pretty thick. I just started using them. So far no problem.
     
  11. 1955

    1955 Doctor of Teleocity

    Posts:
    10,372
    Joined:
    Apr 10, 2010
    Location:
    .
    In my case, which might not be typical in others scenarios, my amp has held up like a champ for a couple hundred gigs, + playing at home regularly. Haven't had to change a tube in so long, I can't remember when the last time was. Just my own experience, but CoolBlueGlow knows amps way better than I ever will, and I'm thankful to learn about this!
     
  12. Johnny Cache

    Johnny Cache Former Member

    Posts:
    1,809
    Joined:
    Mar 6, 2014
    Location:
    Oregon
    If your tubes are rattling replace them.
     
  13. 1955

    1955 Doctor of Teleocity

    Posts:
    10,372
    Joined:
    Apr 10, 2010
    Location:
    .
    It's not always the tube/s, but they do rattle too, as a result of the "other" rattling. Its enough to drive a person nuts if you have ever had to track down an elusive rattle in a combo.

    Otherwise, you just might have spankin' new tubes....that rattle.
     
  14. backline

    backline Tele-Afflicted

    Posts:
    1,522
    Joined:
    Oct 6, 2008
    Location:
    USA, CA, 94585
    Yeah...brand new tubes can rattle...especially in a combo.....
     
  15. CoolBlueGlow

    CoolBlueGlow Tele-Afflicted

    Posts:
    1,536
    Joined:
    Nov 20, 2011
    Location:
    Arkansas
    The amount of heat retention by o-ring dampers is insignificant. It shouldn't cause trouble, and the benefit of dampers on tube life and tone should be measurable. Vibration kills tubes, just like excess current or large jarring impacts or any other physical abuse. Sympathetic resonances in undamped tubes would seem to accelerate tube damage. Extended periods of exposure to vibration of tube elements can cause them to go microphonic, as internal components loosen up by prolonged vibration. Loose parts = microphonic tube.

    I use dampers.

    Heating: Anything that covers more than a few percent of the tube envelope should, in my opinion be reconsidered.

    Interestingly enough, Fender tube shields are wonderful for tube protection and problematic for heating, because of the fact that they are bright silver on the inside. Their high reflective quotient also means the tube does not cool as well. Not a big deal in the 1950's when one could buy a band new RCA black plate 12AX7a at the corner hi-fi shop for $1.90

    With reliably sourced true NOS black plates approaching $100 a pop, I'm trying to stretch all the life I can out of my ever dwindling supply. ;)

    Shields can be chemically blackened with anodization to eliminate the problem, thus retaining the physical and emf benefit. Paint is less effective, because paint acts as an insulator.

    Want to know how much excess heat a tube shield is retaining?
    • Run your amp with one preamp tube shielded and the one next to it not. Let her get good and warmed up.
    • Use a laser thermometer and shoot the exposed glass envelope temp and then the shield temp of the tube next to it.
    • Calculate the temperature difference between these two readings
    • Now add that number to the temperature of the exposed tube. That's how hot your covered tube is actually running inside that shield.
    Check a Mil-E1 spec'd tube data sheet. Does your measured temperature exceed the normal range for longest tube life? If so, add a low speed fan in the back of your combo, blacken your shields or otherwise reduce amp cabinet temp.

    Source: Morgan Jones, BBC
     
  16. gitapik

    gitapik Tele-Afflicted Gold Supporter

    Posts:
    1,052
    Joined:
    Jan 16, 2010
    Location:
    New York City
    Re the "dwindling supply" of good tubes:

    I've got some friends who are convinced that it's no joke. To the point that they've invested heavily on solid state or virtual amps. Anything from a Fender Mustang to an Ax FX2 or Kempler.

    I just can't get myself to go down that road, yet. I'm not a tube snob, but I love tube amps. I just can't imagine, with all the valve amps that are out there, that the supply of tubes would suddenly vanish. Supply correlates with demand.
     
  17. Johnny Cache

    Johnny Cache Former Member

    Posts:
    1,809
    Joined:
    Mar 6, 2014
    Location:
    Oregon
    There are other thinks in combo that can cause a rattle. I had a speaker screw rattle in my Twin Reverb took a while to figure it out. And I found a loose tip off a 1/4 inch cable that broke off in my Deluxe Reverb (how strange that was) gglad it didn't short out something. Combos have lots of vibration especially when cranked. I've found brand new tubes that rattled because the internal mounting stays were not touching the glass and made a vibration or were totally microphonic. I suspect it's more common with todays tubes. Fender used to install tubes that were "STR", (not sure what the letters stand for) they were better at taking vibration than stock tubes like you found in a TV or radio. Maybe thats why some amps come with the dampers? Answer: CHEAP TUBES!
     
  18. Sbax

    Sbax TDPRI Member

    Posts:
    30
    Joined:
    Feb 24, 2013
    Location:
    MN
    Well, that was a very cool post. Never heard of Mil-E-1 spec sheets before. I just read the maximum bulb temperature for a Sylvania 6021 is 220 C.
     
  19. CoolBlueGlow

    CoolBlueGlow Tele-Afflicted

    Posts:
    1,536
    Joined:
    Nov 20, 2011
    Location:
    Arkansas
    Yes, 200ish Centigrade is a typical value for most tubes. The margin for destruction above that maximum is fairly thin. See Mil-E1 for exact vacuum tube operating temperature derating charts. Very enlightening.
     
  20. steveneddy

    steveneddy Tele-Meister

    Posts:
    235
    Joined:
    Jan 16, 2012
    Location:
    Texas
    All of my amps I installed spring loaded tube keepers that press the tubes to the socket - and I buy the little silicone washers that go on top between the keeper and the top of the tube.

    On my KT-66 amps I use that plus silicone rings I get off of ebay.

    But now that I know I may try the hardware store next time for the silicone rings.
     
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.