Locomotive

The Locomotive is a real tube bass overdrive built around a 12AY7 vacuum tube, the same tube type found in the preamp of classic tweed bass amp designs. An internal voltage multiplier boosts the standard 9V DC input to deliver proper operating voltages for the tube, producing warm tube overdrive with excellent touch sensitivity and dynamic response.

Four controls shape the tone: Gain drives the tube circuit from clean boost through aggressive tube grind, Mean sets the output level of the driven signal, Clean blends in the unaffected bass signal to preserve low-end clarity, and Tone adjusts treble response and dynamics. The wide gain range covers everything from a massive clean boost to mean overdriven territory.

A low-impedance output enables use as a standalone bass preamp running directly into a mixing console or power amp. The 12AY7 tube is user-replaceable with other dual triodes like a 5751 for tonal variation.