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Topic: symptoms of a blown transformer(twin)? |
Cody Russell
From:
Arkansas, now in Denver
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Posted 17 May 2013 12:47 pm |
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I have a 70's twin. It get's too hot to touch on the power tube side and lately has been making some ugly high pitch noises once it's been running for a bit.Does this sound like a transformer? Thanks
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carter pro, 66 twin revrerb, steel king, tut taylor dobro, gibson rb 250 |
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Rich Hlaves
From:
Wildomar, California, USA
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Posted 17 May 2013 1:53 pm
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It sounds more like it needs TLC, power tubes, bias and a cap job to me. When is the last time the amp was serviced? Filter & bias caps replaced?
If you loose a transformer it is usually an unforgiving failure. Blown fuse, the amp stops functioning completely etc. If it's the OT it may continue to run but you would hear distorted sounds It's not impossible but I doubt it's a tranny.
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On man....let the smoke out of another one. |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 17 May 2013 3:48 pm
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Heat is normally a bias issue... check your final bias. Watch for red-plating! It should get more than warm, for best sound... but red plates are a no-no.
When the tube is too hot other elements besides the cathode can start to emit... screens, plate, etc. When the plates get red then stuff starts to bend and sag... failure not far away.
As Rich said, a transformer problem is normally very apparent... if it doesn't fail outright, you'll have arcing or other bad-noise issues. How many hours on the set of finals? What about the driver tube? These things do wear out, you know.
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New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 17 May 2013 6:00 pm
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Don't forget to check your fuse for proper value... if it's a 20A fuse then things can soldier along for a while before stuff melts.
Always check the fuse on an amp that's new to you, also. Wrong value = red flag.
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New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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Cody Russell
From:
Arkansas, now in Denver
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Posted 18 May 2013 9:39 am
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I've had the amp serviced recently. I just moved to CO and so I haven't known the tech long. It only gets hot when I'm playing at volume for a while. and not a lot of volume either. just regular stage volumes. I'm going to try a different tech as soon as I can. Thanks for the info. That'll give me some pointers to tell them.
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carter pro, 66 twin revrerb, steel king, tut taylor dobro, gibson rb 250 |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 19 May 2013 8:07 am
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| Cody Russell wrote: |
| I've had the amp serviced recently. I just moved to CO and so I haven't known the tech long. It only gets hot when I'm playing at volume for a while. and not a lot of volume either. just regular stage volumes. I'm going to try a different tech as soon as I can. Thanks for the info. That'll give me some pointers to tell them. |
NBS Electronics is the best place in Denver... go see the ugly old fat fart (Lord Valve) and tell him I sent you.
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New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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