11 Hz ? lol At that point you need more like a siesmagraph.
(don't put cracks in your foundation when trying this).
(what source material do you have that has 11 Hz signal?)
You might try to rent or buy a spectrum analyzer, but I don't know how low they go.
(don't put cracks in your foundation when trying this).
(what source material do you have that has 11 Hz signal?)
You might try to rent or buy a spectrum analyzer, but I don't know how low they go.