Sweeten your tone, boost your signal, and enhance your groove with the MAR Thump Bass Preamp. Built on the circuitry of the original Echoplex Preamp, Thump features a simple yet powerful tone-shaping interface that allows you to find the sound in your head. Separate treble, mid, and bass controls allow you to sculpt your tone to fit any situation. The bass and treble controls are fixed to cut or boost at 4 kHz and 40 Hz respectively, and the mids are sweepable from 250 Hz to 1 kHz for pinpoint control over clarity. The character of the Echoplex preamp is the final secret sauce poured over the top to give you "that" sound. You know, the one you're searching for. Thump delivers big tone that belies its rugged mini housing. You've got room. Make a statement. Be heard. Thump!MXR Thump Bass Features:Based on the '60s Echoplex tape delay preampSeparate treble, midrange, and bass controlsMidrange is sweepable from 250 Hz to 1 kHzMXR Thump Bass Specifications:Input Impedance: 1 MΩOutput Impedance: 100 Ω IMPEDANCETONE CONTROLSBass: + 15/-7 dBV, 40 HzMid: ±16 dBV, 1 kHzTreb: ±10 dBV, 4 kHzFreq Sweep: 250 Hz to 1 kHzNoise Floor: -95 dBVBypass: True HardwireCurrent Draw: 9 mAPower Supply: 9 Volts DC MXR Thump Bass Preamp Pedal.