Simple fixed filters can help you clean up your final mix and make room for each sound, or they can be used for filtering noises and other signals when generating drum sounds, for instance. When the signal goes thru both HP and LP stages, it creates BP.
triple highpass 2-pole filters (cutoffs are approx. 7kHz, 3.5kHz, and 220Hz)
triple lowpass 1-pole filters (cutoffs are approx. (1.5kHz, 4.1kHz, and 880Hz)
passive design > signal drop + no power connection
handmade locally by Bastl Instruments in Brno, Czech Republic
passive design – no power needed