ftp.nice.ch/pub/next/audio/apps/Tuner.N.bs.tar.gz#/Tunerftp.nice.ch/pub/next/audio/apps/Tuner.N.bs.tar.gz#/TunerTuner 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) using the DSP array routines. 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. Although the original version was shareware, Tuner 2.0 is free. Full sources are provided and bug reports and/or suggestions are welcome. This software copyright 1992 -- all rights reserved. Christopher Lane <lane@sumex-aim.stanford.edu>
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.
