Trip to Aitken Audio to work on the T120 prototype

Been working on using the pile of Sound City 120 PAs as a base for new amp builds, since they don’t retain much value, being PAs. Basically, taken a Sunn Model T preamp and built on to updated output section of the 120 (different PI, individual bias), assembled in a bus bar style (sort of like all the stuff people claim of point to point, but true because you can have a good layout with it). Travelled up to Sheffield to visit Aitken Audio with the prototype to get it tweaked and talk plans.


Prototype on the bench having tweaks after first round of testing, addressed some mechanical potential issues, tone control sweep and gain levels.


Blasting it through a vintage Acoustic cab, check it does what its supposed to. Seems a fair bit of instrument character comes through in spite of being driven pretty hard.


Next one started in powder coated chassis.


Also collected this Invader 60 from being sorted. Weird layout, interesting amp, with a pretty good sound, gets pretty snarly dirty when pushed. Plus the tone stack is pretty nice, 2 band, actually does stuff. 2 EL34. £250.


Invader 60 valve amp, novel layout.

This one has been in a damp shed for a while, so will need some drying out and cleaning, because it smells weird.


Knobs on top of the chassis:


Board mount stuff, boo:


Tiny output transformer isn’t my bag, also no impedance selector, hope this isn’t another 100v line job, doubt as has ‘high gain’ inputs.

And the underneath:


Pretty neat wiring, sort of looks like hadn’t really got the idea of the whole PCB thing, with putting loads of wires over it.