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G1619T
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Joined: 03/15/11
Posts: 34
G1619T
Full Access
Joined: 03/15/11
Posts: 34
12/20/2012 7:04 pm
Hi All,
I recently picked up a used Traynor YCV 40 tube amp. It has a single 12" speaker and is rated at 40 watts. It has 3 12ax7 (ECC 83's and two 5881 (6L6GC). I new it wasn't working correctly when I got it. It was ghosting notes. I found a pre-amp tube was causing this problem but, the unit had problems on the clean channel. The distortion channel seemed to work fine. I replaced the output tube and heard something fry. I replaced them again and everything seemed to work fine until I plugged in the foot pedal. It did not work. It seems this amp, and others, use board mounted relays with an optic isolator for switching and the sizzling sound I heard was an optic isolator giving up the ghost. I ended up cleaning the sockets for the tubes, something you should do in the first place, and re-seating them. It works fine except for the channel switching.
I have 12 tube amplifiers from 5 watts to 120 watts. Some I made out of late 50's and 60's hi-fi amps. Changing tubes and re-capping older amps should be the first order of business. Check for resistors that have been over heated and check your wiring. You can select tubes that have various amounts of gain to get a clean sound or a more distorted sound. Also check your bias circuit. I replaced all of mine with an adjustable set up except for the single ended amps and with them I installed two different value resistors in the cathode circuit to select a slightly different sound. Like my Crate V32 is set-up close to a Vox AC-30 except the bias resistor is 60 ohms. I have a switch with a 75 ohm resistor connected so I can select between the two. Their are a lot of web sights up to show you what I'm talking about or get an amp tech you trust to help you out. As your tubes and associated circuitry get old or are heavily used problems start. Be sure, if you do check out your amp yourself, that you turn the unit off to allow the caps to drain and then unplug it.
Regards,
G1619T
# 1
john of MT
Full Access
Joined: 10/08/09
Posts: 1,527
john of MT
Full Access
Joined: 10/08/09
Posts: 1,527
12/21/2012 1:50 am
*The* amplifier designer at PRS started like this...buying and collecting amps. A Dallas architect, he started rebuilding/building tube amps as a hobby (he worked East Europe sources hard to find tubes). Within a few years he was selling boutique amps and eventually met Paul Reed Smtih at a guitar show. Hired away from his architect business, he moved to MD. His designs are now the basis of the line of PRS amps available to us common folk while (his) PRS custom amps are on tour with some top level musicians.

Not bad for a self-taught hobbyist. :)
"It takes a lot of devotion and work, or maybe I should say play, because if you love it, that's what it amounts to. I haven't found any shortcuts, and I've been looking for a long time."
-- Chet Atkins
# 2

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