Resonance in wind instruments

Using the Winscope program record and then examine the frequencies on a string instrument.

As in the previous lab you need to take a screen shot of the wave shape

and open it out by toggling the period (T) button so you can see the shape.

You then use the FFT button (Rainbow button) to isolate the frequencies present.

You will need to create a table of frequencies. Move the mouse to the top of each peak and read the frequency for each. Not all all harmonics may be present. If the peak is above the screen you can toggle the Y1 slider to reduce the amplitude.

Try this for a closed and open pipe

Open pipe

Closed pipe

Questions.

1. Comment on the occurrence and size of each harmonic.

2. How do the overtones (2nd and subsequent harmonics) compare to the fundamental frequency?

3. Is there a difference in the occurrence of overtones in closed pips to open ones?