Harrison Laboratories FMOD 37Hz High Pass 18dB Electronic Crossover

Harrison Labs Subsonic Filter FMOD 37Hz High Pass @18dB Electronic Crossover - Dual female RA adapter included Insert this in the RCA line to your amplifier to help control excessive woofer flapping. This means that it will cut off the low frequencies faster below it's cutoff ...Harrison Labs Subsonic Filter FMOD 37Hz High Pass @18dB Electronic Crossover - Dual female RA adapter included Insert this in the RCA line to your amplifier to help control excessive woofer flapping. This means that it will cut off the low frequencies faster below it's cutoff frequency at a rate of 18dB per octave instead of the typical 12dB.

This allows a lower cutoff but still good protection from over-excursion, Thi