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diff --git a/manual/configure_rockbox/sound_settings.tex b/manual/configure_rockbox/sound_settings.tex
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--- a/manual/configure_rockbox/sound_settings.tex
+++ b/manual/configure_rockbox/sound_settings.tex
@@ -385,3 +385,31 @@ is similar to ``Q'' in the Graphical EQ).
385filters, and High Shelf, the peaking filters are not currently operational.} 385filters, and High Shelf, the peaking filters are not currently operational.}
386 386
387} 387}
388
389\opt{SWCODEC}{
390\section{Dithering}
391This setting controls the dithering and noise shaping functionality of Rockbox.
392
393Most of Rockbox' audio file decoders work at a higher bit depth than the 16 bits
394used for output on the \daps{} audio connectors. The simplest way in which to
395convert from one bit depth to another is simply discarding all the surplus bits.
396This is the default behaviour, and adds distortion to the signal that will
397vary in character along with the desired sound.
398
399Dithering adds low-level noise to the signal prior to throwing away the surplus
400bits, which gives the resulting signal a uniform noise floor which is
401independent of the signal. Most people find this noise preferable to the
402time-varying noise heard when not performing dithering.
403
404After dithering, noise shaping is performed. This basically just pushes the
405dithering noise to the parts of the frequency spectrum humans cannot hear so
406easily. In Rockbox' case, some of the noise is pushed up to above 10 kHz.
407
408This setting will be put to its best use when listening to dynamic music with
409frequently occuring quiet parts, classical music being a typical example. It is
410worth noting that the effects of dithering and noise shaping are very subtle,
411and not easily noticable.
412
413Rockbox uses highpass triangular distribution noise as the dithering noise
414source, and a third order noise shaper.
415}