PICKUPS AND ELECTRONICS

The TCT Family of tone control preamps has Bass, Mid, and Treble controls with very low noise andwide adjustment range. The sound is extremely clear with low distortion. Bass and Treble bandscan be boosted or cut. The Mid band can be narrow notch cut only. An MCT mid boost modulecan be added for full boost and cut of the mid. The TCT family of preamps are powered by a 9 Voltbattery which provides 8-12 months of use. Do not use more than 9 Volts – damage may occur.

Vintage 3-Band Preamp/Tone control

TCT Family

The negative side of the battery should be connected to the jack ring so that power is turned ononly when the plug is in. Unplug the instrument when not in use to conserve your battery. Ensurebridge and cavity shields are connected to ground.

Model Bass Mid Treble Input Impedance Output Impedance Power

TCT +/-12dB@50Hz -16dB@300Hz +/-13dB@6KHz 320KΩ 60KΩ 650uA@9V

NTCT +/-12dB@50Hz -16dB@400Hz +/-13dB@6KHz 320KΩ 60KΩ 650uA@9V

XTCT +/-12dB@50Hz -16dB@500Hz +/-13dB@6KHz 320KΩ 60KΩ 650uA@9V

The TCT Family has 3 models distinguished by their mid cut frequency.

Battery +Ground

Input

BoostOutput

EQ Controls

redblack

yellow

yellow

browngreen

greenwhite

blue

redblack

yellow

yellow

browngreen

greengrey

blue

redblack

yellow

yellow

browngreen

greenorange

blue

TCT NTCT XTCT

This diagram shows a basic setup with Mid Cut control in the electronics cavity. This is a popularsetup for Jazz bass with the Mid fully or partially cut. The Mid trimmer, battery clip, resistors, andcapacitor are included with your preamp.

Mid

25KΩ

Treble500KΩAudio

Bass500KΩAudio

BlendDual

250KΩ5A5C

BridgePickupCable

NeckPickupCable

green

Vol25KΩAudioBa

tter

y +

Gro

un

d

Inp

ut

Bo

ost

Ou

tpu

t

EQ C

on

tro

ls

Cut Onlytrimmer

10KΩ+ -

10uF

Fixed Gain

(Add this Resistor for 3dB more

Gain)

18KΩ

ground

R150619.1

PICKUPS AND ELECTRONICS

MCT

The TCT Family main modules can be mixed and matched with MCT mid boost modules fordifferent mid boost frequencies. The MCT modules provide additional treble boost as well.

Vintage 3-Band Preamp/Tone control

TCT Family

Model Mid Boost Treble Boost Wire Colors

MCT-250 +14dB@250Hz +6dB@2KHz-15KHz brown + purple

MCT-375 +14dB@375Hz +6dB@2KHz-15KHz brown + black

MCT-500 +14dB@500Hz +6dB@2KHz-15KHz brown + grey

MCT-3MC Switchable +14dB@250Hz, 500Hz, or 750Hz +6dB@2KHz-15KHz See diagram pg.3

This diagram shows the wiring for an instrument with 2 pickups to have Volume, Pickup Blend,Bass, Mid, and Treble controls with an MCT Mid Boost Module. This same diagram can be used forTCT, NTCT, or XTCT with any single frequency Mid Boost Module: MCT-250, MCT-375, or MCT-500.The 50KΩ linear taper Mid pot has 47KΩ and 27KΩ fixed resistors for correct biasing of the EQcircuit.

Treble500KΩAudio

Bass500KΩAudio

BlendDual

250KΩ5A5C

BridgePickupCable

NeckPickupCable

green

Vol25KΩAudio

green

black

Bat

tery

+G

rou

nd

Inp

ut

Bo

ost

Ou

tpu

t

EQ C

on

tro

ls

Mid50KΩLinear

black

47K 27K

ground

For additional gain from low output pickups or for blend isolation for improved clarity, a dualbuffer like DB918.2 can be added to the input.

BlendGanged

25KΩMN

blackDB918.2

NeckPickupCable

BridgePickupCable

to battery red

A 25K MN Taper blend is ideal. A 250K blend can be used, but may be noisier. Note that MN and AC tapers are wired in reverse.

PICKUPS AND ELECTRONICS

27KΩ

47KΩ

MCT

Mid50KΩLinear

MCT-3MC VolStacked 250KΩAudio

B/TStacked 500KΩAudio

BlendGanged 250KΩ5A5C

Vol250KΩAUDIO

Active/Passive Wiring for 2 Pickups withBlend control and Master Volume

TCT Family

blackBridgePickupCable

NeckPickupCable

green

green

Stacked Bass/Treble

Bass

NeckPickupCable

BridgePickupCable

Vol250KΩAUDIO

Vol250KΩAUDIO

Active/Passive Wiring for 2 Volumes

In-Cavity Mid Boost/Cut

Mid Switch wiring for MCT-3MC

yello

w

Treble

Wiring Options

brown

750Hz500Hz250Hz

NeckPickupCable

BridgePickupCable

Stacked Volume/Volume for 2 pickupsGround – Connect to cavity shield if available. Also ensure bridge is connected to ground.

to mid

47K

to basson-on-on

switch

27K

10KΩ TrimmerTreble Boost Adjust

to bass green

50KΩ Trimmer