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LADSPA plug-in for emulating the Artificial Double Tracking recording technique
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ADT (part of the StudioBlood LADSPA plugin package, hence the sb_ prefix)
COPYRIGHT (c)2009. Tyler Hayes. Portland, OR. July 31, 2009.


ADT is an audio effect plugin using LADPSA (Linux Audio Developers Simple
Plugin API).  It tries to emulate the ADT (Artifical Double Tracking) technique
invented by Ken Townsend, a studio technician from Abbey Road Studios, for The
Beatles.  Essentially it takes the right channel of a stereo file, and offsets
it a number of milliseconds (specified by the user).  The bounds are 5 and 200

At this point this plugin is ONLY FOR STEREO sound files.  Not only that, but
it is intended to be used with stereo files that have just been converted from
mono (although it can be used with any stereo sound). A mono sound in stereo is
still a mono sound.  But using ADT shifts the right channel of the mono sound
just slightly (as in milliseconds). This does two things at once: creates a
panned stereo sound, and virtually double-tracks the sound.
For example, you lay down a vocal track.  Then apply ADT to it, and you
automatically have two vocal tracks (sung literally exactly the same), and
panned into full stereo.  I say it's 'virtually' double-tracked, because, of
course, it is still only one sound file, and thus, can only be one track.

Mono capabilities is planned, where the second sound that is shifted to create
the virtual second track is placed on top of the existing sound--the same way
delay and such is done.  I haven't learned yet how to do this, but will soon...


It is written in C because the API is in C, and licensed under the GPL v3,
because it's an easy choice when one doesn't want to take the time to
research a bunch of licenses to find 'the right one'.

Thanks to Richard Furse and company for creating ladspa.h, and thanks to Bart
Massey at Portland State University for suggesting LADSPA plugins as a good
open source project to work on.  He also helped me get the correct flags in
the Makefile in order to produce a working shared object file.

I am still a student programmer at the time of this writing, so some of the
comments in the source code are detailed and directed at the beginner as well.
Hopefully the comments will be beneficial to those who were like me in learning
the API, and not too annoying for the pro's out there.

To install, make sure the LADSPA_PATH variable in the Makefile is correct to
your environment, and just run (as root) 'make install'.  You can also run
'make uninstall' (again, as root) to get rid of the plugin.
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