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The whole dynamic area can be within a narrow interval, i.
Pull out the V1 normal channel preamp tube — More preamp gain in vibrato channel.
Very practical mod at practice and low volume environments.
If you pulled the V1 12AX7 tube you may use it as V6 phase inverter.
The reverb circuitry consists of two tube sections reverb driver V3 and reverb recovery V4 and the physical reverb tank.
If you replace the V3 12AT7 reverb driver with a 12AU7, you will reduce the effect of the reverb and it will be much easier to control with the reverb knob. Use normal channel for reverb control — Adjust EQ and depth of reverb.