Tin whistle
In recent years a number of instrument builders have started lines of "high-end," hand-made whistles, which can cost hundreds of dollars US each — expensive in comparison to cheap whistles, but nevertheless cheaper than most other instruments. These companies are typically either a single individual or a very small group of craftsmen who work closely together. The instruments are distinguished from the inexpensive whistles in that each whistle is individually manufactured and "voiced" by a skilled person rather than made in a factory.
Physics of whistles
The Strouhal number
was used as the scaling factor. The highest frequency (7554 Hz) was found in the “overblown” condition and "n" was presumed as one corrugation. At the least flow rate, the frequency of 2452 Hz compared favorably to "n" = 3. At intermediate flow rates, several non-harmonically related frequencies occurred simultaneously suggesting that several corrugations were involved in the sound generation. In the smaller metal tube, a predominant tone appeared at 6174 Hz and corresponded to "n" = 2. A unique aspect of this whistle is that the internal flow carries both the unstable vortex downstream and the returning feedback signal upstream.