Eiron wrote:
Serge Auckland wrote:

I would love to try one of the ultra-low sub-sub woofers that work on
the variable vane principle. They should go down to 0 Hz
theoretically...you could dry your socks in front of one.......
but I doubt there's much actually recorded below 20Hz as current
studio mics don't go down below that.

You could try this sub:
http://www.bkelec.com/HiFi/Sub_Woofers/buttkicker.htm
Perhaps bolt it under your armchair.

I thought there were some organ recordings and that Telarc 1812
with sub 20Hz energy.

I fear the Buttkicker could result in too much excitement.....

There's no fundamental reason why modern digital recordings couldn't go
down below 20Hz, it's just that studio mics generally don't, so how do
you capture the extreme LF? Measurement mics can be made to be flat to
2-3 Hz, but they tend to be rather noisier than "normal" kit and you
have to find a way of protecting them from vlf air movements which can
swamp the recording. I don't know about the Telarc 1812 specifically,
but I understand they used real cannon which would generate huge amounts
of vlf. I wonder what mics they captured it with. Also, the direct to
disk analogue recordings would have to roll off the lf to save the cut
and for the later CD release which was done, if I recall, on an analogue
machine, that would have not gone down below 20Hz, and even 30Hz flat
was a struggle for the Studers and Ampexs of the era.

S.