Quad 33 preamplifier and 303 stereo power amplifier combination. The first amplifier stage is a preamplifier. Before switching to Mesa Boogie, Kisser used an ADA MP-1 MIDI Preamplifier and Marshall amplifiers. PS Audio's first product was a standalone phono preamplifier, sold direct to consumers for $59.95. Eliminating a preamplifier triode in radios made them cheaper. Analog overdrive/distortion pedals work on similar principles to preamplifier distortion. The 1073 is a Class-A design microphone/line preamplifier with three equaliser bands. The output of the preamplifier goes through 2 electronically tuned transistors. The light from the Master Oscillator is split and directed into 48 Preamplifier Modules (PAMs). The transmitter is a preamplifier that may be integrated in another device. It has five 12AX7 tubes in the preamplifier. In either instance, the purpose of the microphone preamplifier is the same. Thus, the cartridge "modulates" an external voltage supplied by the (special) preamplifier. PS audio offered the PCA II preamplifier. This preamplifier is frequently phantom powered in sound reinforcement and studio applications.