TS> I'd like to be able to generate 10+ KW of acoustic 
TS> energy (NOT amp power
TS> ) from 8 Hz through 5 KHz, tapering down to 1 
TS> KW of acoustic energy at
TS> 25 KHz, within an area the size of a 500 person hall.
 TK> Are you into audio or into assassination ?  ;)
Generally I'd just bet cocky people pretending to understand human perception 
of audio better than they do that I could drive them out of the room with 
less than 1/20th of a watt of sound.  >>
Then there was this article in NASA Tech Briefs a few years ago about using 
ultrasonics to create a vibratory crack in the end of a pipe bomb to allow 
cap removal without serious risk of detonation....  
I just thought the above system would offer some interesting design 
challenges, and could trigger an interesting adjunct discussion about little 
discussed transfer efficiency of drivers and coupling systems.  Of course, I 
was thinking about bone conduction of sound to influence brain waves, and 
impose pleasure patterns in such intensity as to be disorienting, or pain for 
more reasons than the listener would understand.  I really wasn't planning to 
raise the issues of living animal tissue damage by sound a couple of serious 
sadists have tried over the years.  
If the above spec's could be met without using more than 150 KW of AC power, 
I'd qualify the system as having an extremely efficient design if based on 
speaker cabinets.  Consumption of under a megawatt max would place it in the 
realm of average small commercial systems.  
How many people here realize that at average home system (in)efficiencies the 
above would require over 5 megawatts of line power in?  
Now, dropping some likely assumptions based on the thread, can you picture a 
more efficient way of producing that energy?  How about a pipe organ with 
about 40 HP of blowers, and a rank of pipes out to 64' added?  That could 
require under 50 KW of AC power in.  
For comparison, the average moderately large church pipe organ has 16' pipes 
and a 3 HP blower, while the largest Austin organ I've ever been inside uses 
a 15 HP blower, a ton of different special pipes on two air chests about 6.5' 
x 15' x 30', but wouldn't produce sound below 16 Hz or at the required volume 
(1922 World's Fair organ in Philly is one of the largest in the world).   
Terry
--- Maximus 2.01wb
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