1. A modular music synthesizer, comprising: an amplifier module providing an audio output; a plurality of circuit modules each presenting the appearance of a specific hardware signal generation or signal modification circuit having user controls simulating the control of the respective apparent hardware circuit module, the plurality of circuit modules being connected in a physical arrangement with each other and the amplifier module; and wherein the amplifier module includes a CPU operating on softsynth software, for emulating the operation of a synthesizer to produce audio output as a function of the physical arrangement of the modules and the status of the controls on each module.