Tuner is a software chromatic tuner for determining the musical pitch of a sound as well as how close that pitch is to the established value for the note. Tuner listens on the NeXT's CODEC microphone input and computes a frequency for the sound it samples. It maps this frequency onto a musical note and displays the value. Then it looks up the standard value for the note to display the difference between the standard value and the computed frequency. The tuner can compute pitch using two different algorithms, by counting zero transitions and by doing a fast Fourier transformation (FFT). You need a relatively simple waveform for the zero transitions algorithm to work -- some instruments and voices work better than others. When it works, it has a potential accuracy of about +/- 1/4 Hz. The FFT algorithm is able to handle more complex waveforms but currently only has a potential accuracy of about +/- 2 Hz. (The zero transitions algorithm works well with recorders and the FFT algorithm works better with bassoons.) The potential range of both algorithms is C00 to B7 and both are further constrained by the limits of the microphone. Read the help panel or Tuner.rtf for details about how to use this utility. Tuner is free, full sources are provided and bug reports and/or suggestions are welcome. This software copyright 1992, 1993 & 1994 -- all rights reserved. Christopher Lane <Christopher_Lane@Med.Stanford.EDU> MusicKit Release 4.1 (beta) copyright 1994 by CCRMA, Stanford University. Lassus font for musical example(s) copyright 1991 by David Rakowski, used by permission. The libfft component is Copyright (C) 1989 by Jef Poskanzer and is bound by: Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. This software is provided "as is" without express or implied warranty.
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.