[Harp-L] RE: Combs - I surrender with my last word

[Jonathan Ross <jross38@xxxxxxxxxxx>]

Derwood Blues writes:

"But I was talking about an electric guitar. Electric guitars, more
specifically solid body electric guitars, do not have a sound board or
"membrane" to project/amplify the sound (unless you want to go all  
the way
to the speaker). "

You must.  In both electric and acoustic guitars it is the membrane  
which generates the sound you hear.  In acoustic guitars this  
membrane is driven by the transfer of vibration from the string, in  
electric by the conversion of the string's vibration into an  
electrical signal.

"The vibration of the string is converted in the pickups. My
point was that the vibrating thing was connected to something solid  
and it's
sound was effected by the properties of that solid thing."

In electric guitars there is a feedback loop which can be caused  
between the body of the guitar and the pickup both vibrating from the  
string.  Solid-body guitars attempt to eliminate this feedback loop  
by making the body of the instrument inert.  In part the differences  
in tone can be ascribed to their success at doing this (though most  
are probably due to pick-up design).  There are other factors too,  
including mounting hardware and similar that effect the way the  
string vibrates and how quickly it looses the energy of the initial  
activation.  None of these are in any way present in a harmonica,  
neither a feed-back loop nor attempts to control or convert the  
energy of the reed to a vibrating membrane nor anything which would  
cause changes in how quickly the reed looses energy (because the air  
activating it controls this factor).  That is why all analogies with  
stringed instruments fail to work--the only significant area of  
similarity in how the sound is produced is in the end result, the  
movement of soundwaves through air.

"I realize that all musical instruments are not the same. But sound is
produced by moving air and there are similarities in a guitar and  
harmonica
that are not there in a guitar and siren. Both a guitar and harmonica  
have a
"tuned" objects that are key in the production of the sound. Both those
objects vibrate. Both those objects result, directly or indirectly in  
sound
being produced."

The siren has a tuned object.  It is the ratio of holes to the speed  
of the rotation.  An effective siren needs the right number of holes  
in the disc at the right speed of rotation.  This is not tuned in the  
way that a harmonica or a string is, but it is tuned.  Moreover,  
while both the harmonica and guitar do have a tuned element, these  
two again work in very different ways.  The guitar string works as,  
well, a string (technically a chordophone, sp), whereas the harmonica  
reed is an idiophone(sp).  In many ways the harmonica reed is more  
similar to a struck bar such as in a marimba or glockenspiel than a  
string.

"When I spoke of lack of testing I was referring to the specific  
effect of
resonance."

You were not specific.  However, I think the term resonance here may  
be dangerous.  There is a lot of testing done in terms of coupling a  
free-reed to a resonant body, usually a form of chamber or pipe.   
There is less in terms of attaching a free-reed to a vibrating body  
(what you are referring to as resonance, from what I can deduce),  
though in many ways that creates a music box or kalimba, for which  
there have been studies.  But, the harmonica is not constructed like  
these and also doesn't produce sound in the same way as these, so the  
way kalimbas or music boxes work and the way harmonicas do are not  
all that similar.  Again, not really any more similar than with  
string instruments.  The key is that at no point is the vibration of  
the reed itself being transfered into a sound producing element.   
Rather, it is the effect of the reed's movement in the airstream  
which is creating the sound.

"I have willingly and humbly listened to those who's ideas challenge and
contradict my ideas and I have learned from the exchange. But it is  
honestly
not an enjoyable exchange when my thoughts seem to be dismissed without
being understood yet with with "expert" accuracy."

I'll echo Vern here in that I have attempted to deal with what you  
wrote directly.  If there were areas I did not cover, feel free to  
ask and I'll do what I can to correct those areas.  If you feel  
questions asked were not answered, point this out and I'll try to  
explain further.  Again in echo, if the problem is that you don't  
like the answers...

" Is sound production with
the result of moving air from two sources truly "entirely different"? "

Yes.  The only significant area of similarity in how the sound is  
produced is in the end result, the movement of soundwaves through air.

"I guess I assumed that I should not be penalized for not having been a
member of the list for years and years. I guess I assumed that this  
was an
exchange of ideas and hypothesis."

I assume that the part about being a new member is in reference to my  
suggesting searching the archives.  I do so not as an insult, but  
because there is a true wealth of information there.  It is more like  
recommending a book--a suggestion for further reading which will help  
as much or more than this thread.





 ()()    JR "Bulldogge" Ross
()  ()
`----'