[pianotech] Discovery surprise

[Ron Nossaman]

On 3/15/2011 10:52 AM, Albert Picknell wrote:

>Perhaps with the second type the sound
> being emitted is just at the edge of my hearing range, and with the
> third type the sound is well beyond my hearing range.  Just guessing.

I can't hear them past the tinnitus (cicadas), so it hasn't been a 
problem for me. It's the folks washing dishes in the next room that hurts.


> I suspect that with long-term exposure, all of them do damage of some
> kind.

I wondered about that. At about 30cm, the level had dropped to 60db, so 
it seems unlikely. Two hours in the room with the A440 band at the 
Yamaha party, however, doesn't seem to worry any of those in atten-dance 
and that feels like damage from way down the hall.


> I wonder what dogs hear when they're around these things.

That occurred to me too. Then I wondered if they'd work as bat 
repellent! I won't put any outside, just in case. I like bats.
Ron N