Subwoofer Amps | High Pass Filters
well i was playing with some tones because i had noticed i was missing some low notes in songs, 100-20hz sweep, onkyo reciever, ep2500 and tc2000 12 in sonotube tuned to ~19-20hz, signal is ran through a ground loop isolator and then a reckhorn b-1
rodny built it for me, i played around alot...