RT

Author:         Kent Dickey and Paul Lansky
Platforms:      ?
Prerequisites:  ?
Price:          free
Demo:           
To acquire:     ftp://lucille.princeton.edu/pub/music/NeXT.rt.MAB.tar.gz
Information:    http://www.music.princeton.edu/PSK/rt.html
Entry updated:  06 Dec 95
Description:    Real-time mixer.

1993, v3.0

           rt is a program which allows the user to play arbitrary parts of
many soundfiles in arbitrary order, and at the same time, i.e. mix
them.  Up to 256 different soundfiles can be accessed and up to 8 can
be played simultaneously.  Note, however, that due to disk and
processor limitations that the maximum aggregate throughput is about
400k bytes a second, which means that the user is limited to 8 22k
mono files, or 4 22k stereo files, or 2 44k stereo files, etc.,  or any
combination of these which lie within the throughput limits (e.g. 2 22k
stereo files and one 44k stereo file simultaneously).  Undoubtedly
these conditions will improve in the future.   (Under certain conditions
disk caching may make it possible to exceed these limitations, but it is
not good to count on this.)
           The interface uses the SubProcess object in the NeXTDeveloper
example.  The rt.driver program, operating as a subprocess,  runs under
control of the interface and must be included in the rt.app directory.
           The data is organized in terms of  sounds  and tracks.  A track
can only play one sound at a time (in two channels).  A sound is an
arbitrary part of any soundfile in any format except mu-law.
(22khz and 44khz, mono and stereo).  A segment of a sound played on a
given track at a given time will be referred to as a note.

With this program you can:
1) Mix soundfiles of different sampling rates and of different formats (mono and stereo)
2) Put envelopes on sound segments.
3) Control gains of left and right channels independently.
4) Control gains of tracks independently, and alter gains over periods of time.
5) Shift the pitch of a note up or down, continuously or instantaneously.
6) Selectively listen to given tracks.
7) Save and restore the state of a given mix in an ascii data file
8) Write a mix to disk, or to the DACs, or to the DSP and external devices.

With this program you cannot (yet):
1) Change the attributes of a mix while it is playing.
2) Have a gain factor greater than 4.
3) Play sounds backwards.
4) Edit soundfiles.