Mechanical tube rattle in brand new Gold Lion KT77's. Opinions?

Discussion in 'Amp Central Station' started by gmm52, Aug 3, 2021.

  1. gmm52

    gmm52 Tele-Meister

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    I just received two Gold Lion KT77's for use in my new 50W Marshall JCM800/JTM45 hybrid clone, and one of the tubes has a pretty distinct metallic sounding rattle with very gentle back and forth motion. I called the vendor, and they're perfectly fine with replacing it, but they thought I should perhaps give the tube(s) a try first, to see if any noise manifests.

    I'd like to hear opinions on whether tube rattle typically manifests when playing. Any other thoughts here would be appreciated.
     
  2. J. Bonkosky

    J. Bonkosky Tele-Holic Silver Supporter

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    Junk is junk. If you can see parts moving inside the tube you will most likely hear it. If nothing else the lifespan of the tube will be shorter.
     
  3. Bendyha

    Bendyha Friend of Leo's Silver Supporter

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    Do you mean - not plugged in, purely mechanical rattle stemming from the bulb not being glued tight in the base, rather than an amplified sound coming from a working tube?

    If so, try the tube under working conditions, and tap it with a chop-stick then to see if there are amplified rattle sounds in the one, more than the other - if so then sending the pair back seems like a wise move. But, it may well be a purely non-amplified syndrome.

    If not microphonic, then the choice is up to you. I have several old tubes that are a bit loose, but sound great, and give me no problems in a cab-amp, where they get the most sonic vibrations. In a head, the vibration is less. One can re-glue as an option for old tubes, but a set of new tubes should basically be delivered firmly set.
     
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  4. clingin_on

    clingin_on TDPRI Member

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    I know it's inconvenient, but at that price I'd be sending them back and requesting replacements. You wouldn't want to run out your warranty.
     
  5. Askwhy

    Askwhy Tele-Holic

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    I've had power tubes that rattled when gently shaken that were fine in amps. I've also had them where they did not make a sound when gently shaken but rattled like a tambourine on certain notes when installed. I would follow the vendor's advice. Play some loud, low notes (with earplugs in) while close to the installed tubes and see if they rattle or make any bad sounds through the speaker.
     
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