Date: Wed, 01 May 2002 08:22:00 -0400

Author: "J. Terrence Klopcic"

Subject: Re: "sound advice"

Post:

Anthony,

I think we're "mixing apples and oranges" here - we're talking about two
distinct media. In the instrument, warmed above ambient temperature:

* the speed of sound is greater in the warmer air
* the resonant wavelengths are dictated by the (slightly temperature
dependent) dimensions of the instrument, and therefore
* the frequency depends upon the temperature-dependent speed

This "system", regardless of its internal characteristics, just acts as a
driver - at a particular set of frequencies - for sound waves in the free
air. The speed at which those sound waves travel in the free air is
relatively independent of the frequency at which they are being driven. The
speed of the free air sound waves is, of course, temperature dependent. And
the frequency is determined by the driver. Thus, in the free air, the
wavelength adapts to match the speed and driver frequency.

Doesn't that seem right?

Terry



----- Original Message -----
From: "Anthony Lapinski"
To:
Sent: Wednesday, May 01, 2002 7:50 AM
Subject: Re: "sound advice"


> When musicians "warm up," the speed of sound in their instruments
> increases. But the pitch will also increase because fn = nv/4L. So does
> this mean that the frequency of the standing wave (note) produced in the
> pipe is higher, but it still reaches our ear at the normal 343 m/s --
> (i.e., frequency does NOT depend on speed)?
>
>

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