Re: Singing pipes

[George Spagna <gspagna@rmc.edu>]

At 03:15 PM 3/19/97 -0500, Rick Swanson cited:
> George Spagna , who wrote:
>
> ...
>
> > Yes  -  we don't use a wire mesh or a newspaper, rather insert a Meeker
> > burner into the pipe.  We have a set of oversized cardboard mailing tubes,
> > and one large carpet roller which shakes the building when we fire it off!
>
> The wire mesh and the mesh over the Meeker burner seem to be the
> mechanism that provides the vibration -- one of the last posts to this
> thread discussed that.  I like the heated mesh inside the tube a little
> better since you get the sound without having to stay over the burner.

Yet  -  I have seen this done with a Bunsen burner (no mesh) or with a plain
old propane torch.  It seems harder to excite the resonance this way.

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?

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