New version of the 3 gain stages rebuild - Marshall JMP 2204 - Hermansson Amplification

Tested out some new ideas for my 3 gain stages rebuild which improved the "chewiness" and the harmonic distortion spectrum. I also developed a new 3-way mid boost/gain boost switch for this circuit to make the design even more versatile. The amp has a totally rebuilt preamp section, new input jacks and new potentiometers, new ground layout for the entire amp, 5W 1 ohm wirewound resistors on the power tube sockets for easy bias measurement, several internal shields to keep the noise floor down. Punch control to control the bottom end of the power end section. The power supply and power amp section have several changes as well. The amp also has a SAG-switch the back to lower the voltage for some extra sag. It can handle a lot of different styles with it's seven 3-way voicing switches. • 3-way tightness switch (hipass filter before the distortion) • 3-way mid boost/gain boost switch (up position adds a mid boost before the distortion, middle position is off, down position adds a full range gain boost) • 3-way punch range switch (set the frequency range for the punch control) • 3-way presence range switch (set the frequency range for the presence control) • 3-way hair switch (adds highs after the distortion, works in a higher frequency range than both the presence and treble controls) • 3-way more mids switch (adds more mids into the main distortion stage) • 3-way fatness switch (cut highs at higher gain settings, at low gain settings it adds bottom end and low mid punch) Guitar straight into the amp, no effects, Malmberg 4x12 cab with 25W 75Hz Greenbacks.