CDs, and other 44.1kHz sampling audio systems, can produce a maximum sound frequency of 20khz in the analog audio range (I'm not sure how the maths goes, but that's apparently true). My question is, whats the minimum frequency you could produce with a 44.1kHz sampling audio system? Is it 20Hz which is roughly the lowest analog audio sound humans can hear, or can it go lower into the infra-sound range?
Of course the CD/sampling system's frequency range would be restricted by the range your speakers/headphones can produce, but I'm more interested in the CD/sampling system's limitations.