ROCK STACK is modeled after the seminal and iconic ’64 Marshall JTM45™ amplifier. Originally based on the Fender Bassman™, it used 12AX7 tubes for more distortion and had an aluminum chassis, to reduce hum. It would be easier to list who has NOT used this amp than who has!

Complete with a full set of amplifier controls, it comes with selectable, high-end mic and preamp combinations. Controls for the head and the cabinet which can be used separately or in combination with other amps. Mix and match heads and cabinets!


  • BASS
    Bipolar control which cuts or boosts low frequencies. 
    Range: 0.00 ~ 1.00
  • MID
    Bipolar control which cuts or boosts mid-range frequencies.
    Range: 0.00 ~ 1.00
    Bipolar control which cuts or boosts high frequencies.
    Range: 0.00 ~ 1.00
    Sometimes referred to as Brilliance or Edge, PRESENCE boosts very high frequencies and slightly rolls off the low end.
    Range: 0.00 ~ 1.00
    The Level knob controls how much signal is sent though the “tubes” in the first gain stage. Higher settings can introduce a pleasing distortion.
    Range: -inf dB ~ 9.54 dB
    Master volume.
    Range: -inf dB ~ 9.54 dB


  • GAIN
    The GAIN switch introduces a gain boost into the guitar amp, like a “High Gain” switch. 
    This is a tone control that when increased simultaneously boosts the high frequencies and attenuates the low end.
    Range: 0.00 ~ 1.00
    Enables or disables the amplifier model.  If the switch is OFF, then none of the amplifier controls will be active. The only active control will be the Speaker Mic and you can use the cabinet with other amp heads.
    Drop-down menu for selecting an impulse response of the speaker cabinet using a variety of preamps and mics.

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