2026-02-14 (Sa) TuningWhistles Concept and modeling

Many of the whistles my wife and I printed were shrill, and we knew that size was the primary factor for frequency, but I wanted to know mathematically how chamber size and frequency related. I hypothesize that length is more important than cross-sectional area because pressure waves travel from the labium (aka ramp or wedge) to the far end and then bounce back. The speed of sound should also be a factor.

I created eighteen whistles in two sets. The set that I printed in black has a 5mm x 5mm cross-section, and the white versions have a 10mm x 10mm cross-section. The air duct and labium are the same design. They were all printed in PLA on one printer. I will measure each whistle's frequency and attempt to find an equation that can help design a whistle programmed to any frequency. With predictable whistles, I can make a set of sixteen bitonal devices that correspond to phone dialing tones (DTMF).

Eighteen whistles with different volumes

The rest of the posts for this project have been arranged by date.

First time here?

Completed projects from year 1
Completed projects from year 2
Completed projects from year 3
Completed projects from year 4
Completed projects from year 5
Completed projects from year 6
Completed projects from year 7
Completed projects from year 8
Completed projects from year 9
Completed projects from year 10
Completed projects from year 11
Completed projects from year 12

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2026-02-08