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.
Whistle register
Many babies and small children regardless of sex can produce sounds in the frequency range of the whistle register without any conscious effort. Typically, the whistle register in children extends from the soprano "high C" (C or 1046.5 Hz) to two Gs above (G or 3136 Hz). Some children, however, can produce pitches that surpass the upper limit of the keyboard.