ref: 8ea7e74252350769f54c4308c821eff68702c6e4
parent: 79d7e54aa6506d8a8271474433d687f13406020a
author: robs <robs>
date: Fri Jul 25 16:05:53 EDT 2008
tidying
--- a/soxeffect.7
+++ b/soxeffect.7
@@ -191,7 +191,19 @@
See also \fBequalizer\fR for a peaking equalisation effect.
.TP
\fBchorus \fIgain-in gain-out\fR <\fIdelay decay speed depth \fB\-s\fR\^|\^\fB\-t\fR>
-Add a chorus effect to the audio. Each four-tuple
+Add a chorus effect to the audio. This can make a single vocal sound
+like a chorus, but can also be applied to instrumentation.
+.SP
+Chorus resembles an echo effect with a short delay, but
+whereas with echo the delay is constant, with chorus, it
+is varied using sinusoidal or triangular modulation. The modulation
+depth defines the range the modulated delay is played before or after the
+delay. Hence the delayed sound will sound slower or faster, that is the delayed
+sound tuned around the original one, like in a chorus where some vocals are
+slightly off key.
+See [3] for more discussion of the chorus effect.
+.SP
+Each four-tuple parameter
delay/decay/speed/depth gives the delay in milliseconds
and the decay (relative to gain-in) with a modulation
speed in Hz using depth in milliseconds.
@@ -198,31 +210,21 @@
The modulation is either sinusoidal (\fB\-s\fR) or triangular
(\fB\-t\fR). Gain-out is the volume of the output.
.SP
-The chorus effect has its name because it will often be used to make a single
-vocal sound like a chorus. But it can be applied to other instrument samples
-too.
-.SP
-It works like the echo effect with a short delay, but the delay isn't constant.
-The delay is varied using a sinusoidal or triangular modulation. The modulation
-depth defines the range the modulated delay is played before or after the
-delay. Hence the delayed sound will sound slower or faster, that is the delayed
-sound tuned around the original one, like in a chorus where some vocals are
-a bit out of tune.
-.SP
-The typical delay is around 40ms to 60ms, the speed of the modulation is best
+A typical delay is around 40ms to 60ms; the modulation speed is best
near 0\*d25Hz and the modulation depth around 2ms.
-.SP
-A single delay will make the sample more overloaded:
+For example, a single delay:
.EX
- play file.xxx chorus 0.7 0.9 55 0.4 0.25 2 \-t
+ play guitar1.wav chorus 0.7 0.9 55 0.4 0.25 2 \-t
.EE
-Two delays of the original samples sound like this:
+Two delays of the original samples:
.EX
- play file.xxx chorus 0.6 0.9 50 0.4 0.25 2 \-t 60 0.32 0.4 1.3 \-s
+ play guitar1.wav chorus 0.6 0.9 50 0.4 0.25 2 \-t \\
+ 60 0.32 0.4 1.3 \-s
.EE
-A big chorus of the sample is (three additional samples):
+A fuller sounding chorus (with three additional delays):
.EX
- play file.xxx chorus 0.5 0.9 50 0.4 0.25 2 \-t 60 0.32 0.4 2.3 \-t 40 0.3 0.3 1.3 \-s
+ play guitar1.wav chorus 0.5 0.9 50 0.4 0.25 2 \-t \\
+ 60 0.32 0.4 2.3 \-t 40 0.3 0.3 1.3 \-s
.EE
.TP
\fBcompand \fIattack1\fB,\fIdecay1\fR{\fB,\fIattack2\fB,\fIdecay2\fR}@@ -420,9 +422,7 @@
pair gives the delay in milliseconds
and the decay (relative to gain-in) of that echo.
Gain-out is the volume of the output.
-.SP
For example:
-.SP
This will make it sound as if there are twice as many instruments as are
actually playing:
.EX
@@ -919,6 +919,8 @@
.B Rej dB
is the level of noise rejection.
The default quality level is `high' (\fB\-h\fR).
+The \-q algorithm uses cubic interpolation; the others use linear-phase
+bandwidth-limited interpolation.
.SP
This effect is invoked automatically if SoX's \fB\-r\fR option specifies a
rate that is different to that of the input file(s). Alternatively, this