I have a subwoofer specially designed for 15-25Hz (Visaton TL-SUB). Front speakers are full range Visaton Casablanca. Problem with all surround receiver-amps is, that the subwoofer cross over frequency is 40Hz as lowest choice. So what I like to develop is an active cross over with a stereo and mono subwoofer output with cross over frequency adjustable between 20 and 30 Hz. Phase shift is no problem since this can be adjusted on the Subwoofer Amp. The biggest problem I foresee is, that the range is so small that I need at least 24dB/octave. I'm curious how this will affect the sound just around the cross over point.
Sub low pass filter
8. Mai 2012