If I don't have a test CD handy, I just take the Telarc recording of Michael Murray on organ with the Atlanta Symphony, of the Poulenc Organ Concerto in G minor, and put it on repeat. 16 Hz pedal tones do the trick!! Just be careful to set the gain at the LOUD part before you walk away!! :duck: (oops, there went the cone flying thru the air...)
Regards,
Gordon.