V2a
Active member
USD$700 + shipping for either amp.
Add $100 for full complement of new tubes (5881 or EL34s in power section)
Completely overhauled YBA-1 amps from the mid 70s. Serviced and modified.
** Service and updating for each amp **
- New 12000-hr caps loaded on my own custom PCBs
- New grounding scheme and some power supply tweaks to make the amp WAY quieter, even with way more gain.
- New 3-prong power cord (with ground switch and death cap removed) for safety.
- Bias trim pot added for quick bias adjustment.
- Original fragile wires replaced for reliability (essentially, all original wires will break if lightly stressed).
** tone mods, Amp 1 **
Similar to single-channel Friedman Smallbox, with Low- and High-sensitivity inputs for 2 or 3 gain stages, respectively. Depth knob on rear panel. Mini switches for bright/bite (three position), gain structure, Fat, and 'era' (low/high gain for high-sensitivity input).
** tone mods, Amp 2 **
Single-channel SLO-based mod with low- and high-sensitivity inputs for 3 or 4 gain stages, respectively. A solid-state source follower was built on a custom PCB to drive tone stack (since I didn't want to drill the chassis for another 12AX7). SLO preamp values tweaked a bit, similar to what Baron55 recommended on the SloClone forum. Depth knob and Fat/tight switch added on rear panel.
Amp 1:
Amp 2:
Amp cover:
Add $100 for full complement of new tubes (5881 or EL34s in power section)
Completely overhauled YBA-1 amps from the mid 70s. Serviced and modified.
** Service and updating for each amp **
- New 12000-hr caps loaded on my own custom PCBs
- New grounding scheme and some power supply tweaks to make the amp WAY quieter, even with way more gain.
- New 3-prong power cord (with ground switch and death cap removed) for safety.
- Bias trim pot added for quick bias adjustment.
- Original fragile wires replaced for reliability (essentially, all original wires will break if lightly stressed).
** tone mods, Amp 1 **
Similar to single-channel Friedman Smallbox, with Low- and High-sensitivity inputs for 2 or 3 gain stages, respectively. Depth knob on rear panel. Mini switches for bright/bite (three position), gain structure, Fat, and 'era' (low/high gain for high-sensitivity input).
** tone mods, Amp 2 **
Single-channel SLO-based mod with low- and high-sensitivity inputs for 3 or 4 gain stages, respectively. A solid-state source follower was built on a custom PCB to drive tone stack (since I didn't want to drill the chassis for another 12AX7). SLO preamp values tweaked a bit, similar to what Baron55 recommended on the SloClone forum. Depth knob and Fat/tight switch added on rear panel.
Amp 1:
Amp 2:
Amp cover:
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