Re:Projection

["Rick Dempster" <rick.dempster@xxxxxxxxxxx>]

Pat;
      Thanks for your interesting reply regarding the comparison of the music box and the harmonica. I am familiar with
the terms you use (idiophone, linguaphone) and looked up the one I didn't know (aerophone) in Groves.
      In fact I came upon the first two at http://www.asza.com/ihm.shtml#Free%20Reeds which I found through your site.
Very interesting too. I am fascinated with the Asian free reed instruments, in particular the Khaen (Got one too, but it
was made for the tourist shops and half the reeds are missing!)
      I still do not see what the effective difference is between the plucked and blown reed. I know that the airstream
amplifies the sound. I discovered some years back in a physics journal an article on one of the very early sound
amplification systems used in the Royal Albert Hall to amplify phonograph records to accompany films, which involved
compressed air passing through the speaker horn. 
     Thinking that this could be used to 'naturally' (ie non-electronically) amplify the harmonica, I suggested it (via
harp-l I think) and got the reply, I think from one W.Vern that this is what already takes place in the harmonica.
      Can you explain what is the difference between the vibrations produced by plucking, and those produced by an air
stream? The reed must be producing the sound, otherwise what difference would its mass/ length etc. make (I can see I'm
going to have to conduct my own experiments to understand this, ultimately!)
      Finally, can you imagine anyway of increasing the volume of the harmonica without electricity? Is this the
free-reed equivelant of the quest for perpetual motion?
Cheers,
Rick Dempster