This jumper set uses four jumpers to tailor audio output on compatible speakers. Jumpers A and B control the bass range, while Jumpers C and D control the high range. What you get and how it works - Jumpers A and B (bass control) - A sets the lower limit of the bass range; B sets the upper limit. - On some speakers, turning the bass up too much can cause distortion. - Jumpers C and D (treble control) - When the caps on C and D are fitted, the highs are the loudest. How to adjust for best sound - If distortion occurs from strong bass - Remove Jumper A's cap to limit super-deep bass and reduce distortion. - To increase bass - Remove Jumper B's cap. With the B cap on, bass is reduced. - To maximize highs - Leave the caps on Jumpers C and D to achieve the loudest highs. Benefits and practicality - Fine-tune bass and treble to match speaker performance - Reduce distortion while preserving desired bass impact - Simple, cap-based adjustments with no software required - No size or material specifications provided; designed for use with compatible audio devices and speakers Use scenarios - Home theater with powerful bass: remove A cap to limit deep bass and reduce distortion, adjust B cap as needed. - Stereo listening wanting stronger bass: remove B cap to increase bass, keep A cap as configured to avoid distortion. - Bright, detailed listening on treble-focused tracks: ensure C and D caps are on to maximize highs.