Re: Noises through pickups (rather gongs...)

[Pohon-Kelapa@t-online.de (Martin Tauchen)]

So true,eventhough this low tone is not really produced,nevertheless
we can "hear" it.
The reason is simple.Our ears can also be tricked-or missinterpret-
an acoustic effect,like our visible recognition.
In this case,we hear from a bell all overtones/harmonics,but the
"Base Tone" is physical missing.Our brain now adds this missing 
first harmonic to the reall appearing overtones and so we hear also 
this low base-overtone of the harmonic spectrum of the bell.

This effect is also used for such devices like Subharmonic Exciters and
Psychoacoustic-effects devices.Bring in the sound more bass,without
changing the volume of a signal.

There are also other nice audiorelated phenomens to trick our audible
recognition.Like the Sheppards Effect,with an infinitley,decreasing
sound.

Martin









Allan Hoeltje schrieb:
> 
> First, let me apologize if I've been dragging this bowl thread on too
> long.  Personally, I've found the discussion to be very interesting and
> relevant to Looper business.  If it hasn't been resonating for you hit
> delete now.
> 
> Second, someone here (don't remember who and it's been deleted) said it
> is physically impossible for singing bowls to produce the low tone that
> you hear.  Maybe what they really meant was "physically incredible"
> because, since you _do_ hear the tone, it is indeed possible.  I
> remember some years ago reading about bells and the mathematical formula
> for determining the "perceived" fundamental frequency.  The word
> perceived is important here because bells are not like organ pipes or
> strings.  Organ pipes and strings actually produce their fundamental
> tone.  Bells do not.
> 
> Bells produce overtones of what we perceive to be the fundamental tone.
> This is were my memory escapes me but I seem to remember that a bell
> produces a low frequency vibration which is below human hearing and
> overtones which we do hear.  It is the sums and differences of this
> inaudible low tone and the interaction with the overtones which produce
> the perceived fundamental.  This is also why the sound of a bell seems
> to come not from the bell but from the space around it.  No mystical
> mystery, just nature being its wondrous self.  :-)
> 
> Third, I have not procured a real Tibetan singing bowl yet but last
> night I was feeding my two cats.  One of their bowls is a 6" stainless
> steel bowl.  It dawned on me that it came from a set of six bowls of
> increasing size up to 16" in diameter.  Imagine my surprise when I took
> a wooden potato masher and rubbed the edge of the 16" bowl with just the
> right circular motion.  My 18 year old cat is stone deaf but he stared
> at me mesmerized by the intense low sound emanating from the bowl - it
> was probably the first thing he has "heard" in years!  I am sure
> stainless steel is no substitute for high quality bronze alloy so I can
> only imagine what a real 16" singing bowl must be like.
> 
> Anyway, once again the folks on Looper's Delight have directed my sonic
> fascination on to a new and exciting tangent.  Singing bowls are now on
> my "must get" list of looper gear.  Thanks to all who have contributed!
> 
> -Allan