Produce sound of specific frequency in Windows Console.

1. Download exe file.
2. Copy to C:\Program_Files\Scripts.
3. Add C:\Program_Files\Scripts to PATH environment variable.

> esound <frequency> <time>

:: [] -> optional argument
:: <> -> argument value

:: a 500Hz sound for 1s
> esound 500 1000

:: a 1kHz sound for 250ms
> esound 1000 250

:: silence for 10s
> esound 0 10000