You wrote;
> What would be really cool though is to modulate the sound you were
> transmitting on a frequency that would be the resonance of one
> particular person's eardrum. Then you could send it to only one
> person (or maybe a few choice dogs <g>).
You realize of course that all mass picks up essentially all
frequencies.
Resonance is just the frequency which is BEST picked up.
Take a speaker, it can transmit from subaudible (less than about 14 cps)
up to ultra audio (greater than about 20 cps), but it has the highest
efficiency of energy transfer at its resonant frequency.
The bigger the cone, the lower the resonant frequency.
So, it would not be possible, at least that I can see to transmit ONLY
to one ear using a single resonant frequency (modulated with audio).
However, the Neurophone ( http://www.flantech.com ), newest version
called the Thinkman about $700.00, is claimed to transmit at the
resonant frequency of the nervous system of the user. This frequency
changes, but has a general range of 50kcps up to about 100kcps.
I have a Mark 11 Neurophone and it sucks despite all the wonderful
claims I'd heard all these years. There are people who say the new
Thinkman works beautifully, that you simply touch the electrodes to your
skin and you can hear music or audio CLEARLY inside your head.
I have yet to experience this phenomenon and blew the chance of getting
a freebie from Flanagan by giving Terry Bastian the 'reverse engineered'
Mark 11 Neurophone plans which are on his website at;
http://www.bdsnet.com/~tabastian
-- Jerry W. Decker / jdecker@keelynet.com http://keelynet.com / "From an Art to a Science" Voice : (214) 324-8741 / FAX : (214) 324-3501 KeelyNet - PO BOX 870716 - Mesquite - Republic of Texas - 75187