[sdiy] Low Pass filters and musically useful frequency range

[David Ingebretsen]

The basic question revolves around the output stage of the Moog 914 fixed
filter bank and the fact it incorporates a highpass filter with a cutoff
around 40-60 Hz depending on how you want to define the -3dB point.

Questions:
1. As a general proposition and in a purely subjective context, what is the
lowest frequency that is musically useful?  At some point most waveforms
start to sound like clicks and pops. Subwoofers can pound your
proprioceptive system and add a useful effect I suppose but "how low can you
go" and still be musical?

2. Why would Moog add such a high pass filter to the 914? I can see blocking
DC, but why worry about 10 Hz getting through? Does it have to do with being
musically useful? I don't think this high pass filter was in the 907, so why
add it to the 914?

Thanks

David