Re: Singing pipes

[George Spagna <gspagna@rmc.edu>]

> On Wed, 19 Mar 1997, George Spagna wrote:
>
> > BTW a good lab exercise is to obtain a power spectrum of the pipe  -  when
> > we do it the dominant (loudest) frequency is not the fundamental but the
> > first overtone.  Anyone with insights why that mode should be easier to
excite?

At 09:09 AM 3/20/97 -0500, Richard Bowman responded:

> I have not done this experimentally, but my guess is that it depends upon
> the length of pipe. For some pipes the turbulence around the wire mesh
> will cause its most efficient oscilations at the fundamental and for
> others it will be at an overtone. Does the size of the holes in the mesh
> effect which frequency is most efficiently expressed?

Two thoughts  -  

1.  It occurs to me to check the power spectrum of the "hiss" from the burner.

2.  We've seen the first overtone dominate for pipes of 3.5, 4, and 8 feet,
all with the same burner.  If the coupling efficiency depends on the hole
size in the burner, this is a very broad Q  -

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