Fresh_Start
New member
It lives & breathes & makes music... or at least it would if I were any good at playing guitar...
This is my second build based on the Princeton Reverb circuit. In addition to improving the grounding arrangement and power filterings, there are a few other changes:
- Raised supply voltage to phase inverter to increase voltage and headroom at the PI. This is called the "Stokes mod" IRRC and is supposed to let the amp push the power tubes harder.
- Mid control with 50K pot to get part of "raw" control. May convert to a 10K pot with a pull switch to insert a 50K resistor instead.
- Ruby type 9AB2C1B reverb tank (3 springs, medium delay)
- Dwell control
- NFB switch currently doubles value of negative feedback resistor, reducing NFB. Resistor values subject to change.
- Tweaked signal cap values to reduce bass and remove boominess in reverb.
Slideshow
Other data points:
Hoffman transformers
Weber 10F150-T speaker
Mojo cab & chassis
Many thanks to all of the wonderful guys at the Hoffman forum
Chip
This is my second build based on the Princeton Reverb circuit. In addition to improving the grounding arrangement and power filterings, there are a few other changes:
- Raised supply voltage to phase inverter to increase voltage and headroom at the PI. This is called the "Stokes mod" IRRC and is supposed to let the amp push the power tubes harder.
- Mid control with 50K pot to get part of "raw" control. May convert to a 10K pot with a pull switch to insert a 50K resistor instead.
- Ruby type 9AB2C1B reverb tank (3 springs, medium delay)
- Dwell control
- NFB switch currently doubles value of negative feedback resistor, reducing NFB. Resistor values subject to change.
- Tweaked signal cap values to reduce bass and remove boominess in reverb.
Slideshow
Other data points:
Hoffman transformers
Weber 10F150-T speaker
Mojo cab & chassis
Many thanks to all of the wonderful guys at the Hoffman forum
Chip
