Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Kaptinkangaru on September 26, 2026, 09:31:20 pm
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Here's one i did earlier this year- a Trainwreck Express clone, making about 45 watts from two EL34's. Pacific Audio Trainwreck transformer set. Sylvania 5751 V1, Sonotone 12AX7 V2, JJ 12AX7 V3, Mullard reissue EL34's. DC heaters for the preamp from a Recom brick, AC to the power tube filaments. Used a 17x6x3 chassis because i didn't love how most builds, including originals, had the transformers practically on top of each other. Circuit laid out in EasyEDA, milled on desktop CNC, faceplate laser engraved then milled. Still need to build a headshell one of these days, picked up a nice etimoe slab a few months ago, havent had the time yet.
some clean playing:
https://photos.app.goo.gl/TqX9VBCUAhpyS2bX8
and with the volume cranked(into an attentuator of course):
https://photos.app.goo.gl/MgKsUjywW7qDBxGG8
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couple more shots of the board front and back, and the faceplate under the laser.
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Excellent build! Sounds and looks great.
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It looks great, but with the lead dress of the OT primary wiring (and its proximity to the input / early stage circuitry), I'm surprised it's stable.
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It looks great, but with the lead dress of the OT primary wiring (and its proximity to the input / early stage circuitry), I'm surprised it's stable.
It was definitely a concern of mine, as the OT wires needed extending regardless. I tested with longer leads away from the board, zero difference in noise/interference. From the sound of it, it seems pretty happy to me.
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Always good to see that a Trainwreck Express is born.
Nice work! Looks amazing!
These are the two I built
Trainwreck Express Cesspool style.
With a Fender Basseman tone control.
PostPI Master and half power reduce switch.
Dumbleater-based Tube FX
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more pics.
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Last one.
I forgot the bias print,now attached :icon_biggrin:
complete build : https://zelfbouwaudio.nl/forum/viewtopic.php?t=32462
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Last one.
I forgot the bias print,now attached :icon_biggrin:
complete build : https://zelfbouwaudio.nl/forum/viewtopic.php?t=32462
Looks great, hoping to find the time this winter for some woodwork, nice inspiration
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Love the artwork
Got me thinking
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Nice job, very cool faceplate top
Franco
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couple more shots of the board front and back, and the faceplate under the laser.
Nice work for a single sided PCB.
Are those Xicon or Panasonic ECQ coupling caps?
--Pete
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couple more shots of the board front and back, and the faceplate under the laser.
Nice work for a single sided PCB.
Are those Xicon or Panasonic ECQ coupling caps?
--Pete
Its been a few months, but from what I can see and recall, I used Nichicon snap ins and radials in the power section, as well as a couple Panasonic Elcos in the audio path. Film caps are likely a mix of some Panasonic, Cornell Dubliner, and Kemet, whatever i had on hand in the chosen value. I'm a big believer in tech specs, not snake oil.....