Can anyone give an example of something that gives off a sound in, say the 15-20 kHz? What about something in the 40-20 Hz? How high is that buzz I always hear from my t.v. set?
I messed with the tone generator a bit and it does sound like the TV hiss noise is probably in the 15-20khz range. Here is what a 15 to 20khz sweep sounds like.