TCT is the legendary original Bartolini onboard preamp. It has bass, mid and treble controls with very low noise and wide adjustment range. It has vintage FMV (Fender/Marshall/Vox) frequency controls so each band affects the others, and if all bands are set to minimum, the output is muted. The TCT preamp has a voice of its own, providing vintage color to your sound. It has a mid-frequency notch at 300Hz for legendary slap tone. TCT is the first Bartolini preamp with inter-dependent controls, so it is a tone-shaping preamp rather than a strict EQ requiring expertise.

A professionally pre-wired and fully pre-tested harness saves the time and aggravation of wiring your preamp and pots into your instrument. Wired with Bartolini's pro-level preamp and premium audio-quality pots and switches, you’ll have smooth control and be ready for years of rugged use. The include battery clips and an output jack make it easy for quick installation. All the pots are grounded with a wire that can be connected to the cavity shield or simply cut away if not needed in your installation. Everything is pre-soldered with pro-quality pure copper wire that is double tin-plated and protected with semi-rigid insulation so it won’t flop around in the cavity or degrade over time. Bartolini uses only professional lead-free solder with non-corrosive flux. Knobs are a personal choice, so they are not included with the harness–except where there is a stacked (concentric) pot, in which a ring knob and center knob is included since they are not as common.