# Velocity of air, period, flutes and resonant frequencies

1. Nov 26, 2007

### ajd17

Hi,

We were talking about the speed of air expelled from the mouth as it passes over the embouchure hole of a flute, and I'm having trouble understanding part of the concept. At one point, in the notes, I have if the velocity of the airstream is greater than the period of the flute cavity's resonance frequency, then the deflections created by the airstream will not help the high frequency oscillations self-reinforce. Later the prof says if the resonant frequency in the flute's cavity is below the airstream resonant frequency, then this is the optimum speed for driving the resonance.

I like numbers as ways of explaining but I am not a mathematician, so if someone would give me an example of airstream velocity and the period of a frequency where the velocity of the airstream is higher, that would be great. I'm stuck at the understanding that velocity is m/s, while period is measured in seconds, or frequency is measured in cycles per second. If someone would be so kind as to show me how to make the correlation between the two (formulas??), that would be appreciated.

And no, this is not a homework question, although understanding this will help me when it comes time for the final.

Thanks,
ajd