Thanks for your reply garics and yes it is 2Hz. I just finished checking it on Denon's site. Thanks for the info on Brainwave Generator. I downloaded the software last night and am making wave files for most of the presets. You mentioned the possibility of lowering the carrier frequency. I'm not sure how to do that. Any ideas? Also, I noticed that the presets end abruptly with no fade-out. Do you know if there is a way I can fix this? Perhaps by masking the tones with another sound file, say nature sounds? Again, thanks for replying.