Re: [Phys-L] sound

[Paul Nord <paul.nord@valpo.edu>]

Excellent question.

Yes, just as you suspect, there are multiple resonances in the bugle.  The resonance which sounds is a function of the driving frequency.  This means that such an instrument can only play certain notes of the scale.  There may be a small range around those pitches which will sound.  But, principally you are limited to those notes because of the fixed length of the instrument.  On a valved brass instrument like a trumpet the valves cut off or add lengths of pipe.  Each valve position allows a different harmonic series to sound.

See:
Bugle - Wikipedia, the free encyclopedia

And compare those notes which the bugle can play to the melody for Reveille or Taps.  These songs are played on just these notes because each is written for the bugle. 
Reveille - Wikipedia, the free encyclopedia

Paul


On Apr 12, 2013, at 6:21 AM, "Anthony Lapinski" <Anthony_Lapinski@pds.org> wrote:

> Does anyone know how a bugle produces different notes (as it has no keys,
> valves, slides, etc.)? I know the instrument when played is physically
> closed, but it behaves like an open pipe due to the bell's conical shape.
> So the harmonic series is fn = nv/2L The length of the instrument is
> constant, so does the player just blow/buzz his/her lips faster? or with a
> higher frequency? That changes the harmonics/frequencies, but does that
> change v in the equation? I thought v was the speed of sound in air (343
> m/s) for brass instruments. I'm a bit confused with some of the finer
> details of this "simple" instrument.
>
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