igh headroom, low-noise, 3-Band active onboard EQ preamp voiced specifically for fretless basses with PASSIVE pickups. Designed to be used with passive pickups, this version of our Tone Circuits will add a tremendous amount of on-board tonal versatility to any bass with 2 passive pickups. Our design enables players to boost or cut specifically focused frequencies in order to achieve signature tones and to dial in a great sound no matter what the situation. The STC-3PSB provides bass and treble controls, a midrange control, a master volume, a blend control, and our special frequency contour switch. This preamp was voiced by Steve Bailey to have three bands of focused EQ, together with a switch that engages a frequency contour optimized to bring out fretless harmonics as well as mid-range boost. The frequency contour is engaged by pulling up of the volume control. We even added two small trim pots on the circuit board can be tweaked to preset the frequency contour EQ just the way you want.