The EMG BQS Active Bass EQ System is a complete control system for bass guitars. Active Balance, Master Volume and EQ circuits are included. They allow you separate control over bass, midrange, and treble. Rotate the controls clockwise to boost, counterclockwise to cut. There is a center detent for flat response.
The mid-range control has a variable frequency knob that allows you to sweep through the mid-frequency range from 100Hz to 1KHz. This selects the frequency to boost or cut.

Included in the BQS System system

- Active Balance Control (B118)
- BQS Control
- Master Volume control, output jack, battery buss and clip.
- Wiring Harness
- Knobs

The ABC Control is designed for EMG Active Pickups

It allows loss-free balance between two pickups and has a center detent for the middle position. If you are using EMG-HZ Passive pickups, or other passive pickups you will want to use the B125 Active Balance Control which features buffered inputs for passive high impedance pickups.

BQS Control 3-band equalizer for Bass guitar

The BQS features dual-pole filters for broadband equalization. The primary feature of the BQS System is the variable mid-range frequency selection from 100 to 1KHz along with boost or cut of the chosen frequency. An additional feature of the BQS Control is a 2-position dip-switch that controls the slope of the high frequency response. By choosing one of the four combinations the high frequency response can be tailored to your liking.