Audio crossover filter - a three-way crossover filter that enables upgrading or converting speakers to a 3-way system. It provides proper frequency separation to drive the appropriate drivers for clearer mids and tighter bass. Bass height divider - a multi-purpose frequency divider that can be fully assembled and welded, acting as the speaker crossover filter for bass and low-frequency management in a DIY build. Speaker frequency divider - printed circuit board design with precise cut-outs and lines for welding, very suitable for DIY enthusiasts and acoustic components. Audio frequency divider - suitable for stereo systems and speakers, ideal for bass three-way DIY or sound quality upgrades, and serves as a reliable frequency distributor. Use scenarios - Upgrade a bookshelf stereo by installing the 3-way crossover to improve bass control and overall tonal balance. - Build a custom 3-way speaker from scratch using the PCB crossover as the core frequency-distribution network. - refurbishment of older speakers by replacing worn crossovers with this PCB-based solution to restore performance.