Hermansson Amplification
Active member
My latest project is this Sound City PA 120R which had a solid state preamp and a tube power amp section. It was a good platform with it’s big transfromers and room for a lot of controls and functions on the big front panel. It has now become a four channel amp, all tube of course with a footswitchable gain boost (extra tube stage) for each channel and dual footswitchable master volumes. So it has eight footswitchable sounds which can all get a volume boost for solos. Other features are tube buffered effects loop and bias potentiometers and test point jacks for each of the six EL34’s on the back panel.
Here you can see the guts of the amp before I did my work in it:
I took out all parts except for the good old transformers and the tube sockets + impedance and voltage switches:
Making turret boards:
All cables attached to the turret boards:
Turret boards populated with components which makes it a totally different amp:
Preparing the amp to receive the turret boards:
And attaching all the cables where they are supose to be:
And here we have the finished result:
Controls for each of the four channels: gain, three way mid boost switch, bass, middle, treble and volume + a footswitchable gain boost.
Controls for the power amp: dual footswitchable master volumes, presence and punch both with a three way range switch to match the amp to different cabinets.
Here you can see the guts of the amp before I did my work in it:
I took out all parts except for the good old transformers and the tube sockets + impedance and voltage switches:
Making turret boards:
All cables attached to the turret boards:
Turret boards populated with components which makes it a totally different amp:
Preparing the amp to receive the turret boards:
And attaching all the cables where they are supose to be:
And here we have the finished result:
Controls for each of the four channels: gain, three way mid boost switch, bass, middle, treble and volume + a footswitchable gain boost.
Controls for the power amp: dual footswitchable master volumes, presence and punch both with a three way range switch to match the amp to different cabinets.
