diff --git a/doc/4-instrument/MPCM-ADSRchart.png b/doc/4-instrument/MPCM-ADSRchart.png
new file mode 100644
index 000000000..254a39bd8
Binary files /dev/null and b/doc/4-instrument/MPCM-ADSRchart.png differ
diff --git a/doc/4-instrument/multipcm.md b/doc/4-instrument/multipcm.md
index c31e90aab..6306af506 100644
--- a/doc/4-instrument/multipcm.md
+++ b/doc/4-instrument/multipcm.md
@@ -8,15 +8,20 @@ for sample settings, see [the Sample instrument editor](sample.md).
 
 ## MultiPCM
 
-MultiPCM contains an ADSR envelope, not unlike Yamaha OPN/OPM envelpes, and simple LFO, also similiar to that found in OPN.
+MultiPCM contains an ADSR envelope, not unlike Yamaha OPN/OPM envelopes, and simple LFO, also similiar to that found in OPN.
+
 you may use this tab to set up MultiPCM-specific parameters:
 
-- **AR**: sets attack rate.
-- **D1R**: sets Decay 1 rate.
+- **AR**: sets Attack Rate.
+- **D1R**: sets Decay 1 Rate.
 - **DL**: sets Decay Level (analogue of Sustain Level on OPN chips).
-- **D2R**: sets Decay 2 rate (a.k.a. SR, Sustain Rate).
-- **RR**: sets release rate.
-- **LFO rate**: sets speed of LFO.
+- **D2R**: sets Decay 2 Rate (a.k.a. SR, Sustain Rate).
+- **RR**: sets Release Rate.
+
+![MultiPCM envelope chart](MPCM-ADSRchart.png)
+
+- **RC**: sets Rate Correction amount. similar to Key Scale or Rate Scale in FM parameters, this determines the degree to which the envelope execution speed increases according to the pitch.
+- **LFO Rate**: sets speed of LFO.
 - **PM Depth**: sets depth of LFO vibrato.
 - **AM Depth**: sets depth of LFO tremolo/amplitude modulation.
 - **Damp**: enforce quickly fading out the sample over 11 ms.
diff --git a/doc/7-systems/ym2203.md b/doc/7-systems/ym2203.md
index d51b039de..b92290914 100644
--- a/doc/7-systems/ym2203.md
+++ b/doc/7-systems/ym2203.md
@@ -123,6 +123,12 @@ SSG-EG is short for "Software-controlled Sound Generator – Envelope Generator"
 
 a full guide to SSG-EG is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU), this [detailed technical explanation](https://gendev.spritesmind.net/forum/viewtopic.php?t=386&start=106), and this [chart of tunings](https://docs.google.com/spreadsheets/d/1HGKQ08CnLGAjA1U0StJFldod3FkQ3uq86rYy1VBIuZc/).
 
+## CSM
+
+CSM, or "Composite Sine Mode", involves a timer matching the frequency of the note in the "CSM Timer" channel. each time it triggers, it generates key-on and key-off commands to reset the phase of all operators on channel 3 and force their envelopes to restart at the release point. this can be used to create vocal formants (speech synthesis!) or other complex effects. outside this chip's specific implementation, the technique is known as "oscillator sync".
+
+working with CSM is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU).
+
 ## chip config
 
 the following options are available in the Chip Manager window:
diff --git a/doc/7-systems/ym2608.md b/doc/7-systems/ym2608.md
index b2cb91a41..570883569 100644
--- a/doc/7-systems/ym2608.md
+++ b/doc/7-systems/ym2608.md
@@ -123,6 +123,12 @@ SSG-EG is short for "Software-controlled Sound Generator – Envelope Generator"
 
 a full guide to SSG-EG is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU), this [detailed technical explanation](https://gendev.spritesmind.net/forum/viewtopic.php?t=386&start=106), and this [chart of tunings](https://docs.google.com/spreadsheets/d/1HGKQ08CnLGAjA1U0StJFldod3FkQ3uq86rYy1VBIuZc/).
 
+## CSM
+
+CSM, or "Composite Sine Mode", involves a timer matching the frequency of the note in the "CSM Timer" channel. each time it triggers, it generates key-on and key-off commands to reset the phase of all operators on channel 3 and force their envelopes to restart at the release point. this can be used to create vocal formants (speech synthesis!) or other complex effects. outside this chip's specific implementation, the technique is known as "oscillator sync".
+
+working with CSM is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU).
+
 ## chip config
 
 the following options are available in the Chip Manager window:
diff --git a/doc/7-systems/ym2610.md b/doc/7-systems/ym2610.md
index 2edcfaf6d..d8279e833 100644
--- a/doc/7-systems/ym2610.md
+++ b/doc/7-systems/ym2610.md
@@ -121,6 +121,12 @@ SSG-EG is short for "Software-controlled Sound Generator – Envelope Generator"
 
 a full guide to SSG-EG is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU), this [detailed technical explanation](https://gendev.spritesmind.net/forum/viewtopic.php?t=386&start=106), and this [chart of tunings](https://docs.google.com/spreadsheets/d/1HGKQ08CnLGAjA1U0StJFldod3FkQ3uq86rYy1VBIuZc/).
 
+## CSM
+
+CSM, or "Composite Sine Mode", involves a timer matching the frequency of the note in the "CSM Timer" channel. each time it triggers, it generates key-on and key-off commands to reset the phase of all operators on channel 2 and force their envelopes to restart at the release point. this can be used to create vocal formants (speech synthesis!) or other complex effects. outside this chip's specific implementation, the technique is known as "oscillator sync".
+
+working with CSM is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU).
+
 ## chip config
 
 the following options are available in the Chip Manager window:
diff --git a/doc/7-systems/ym2610b.md b/doc/7-systems/ym2610b.md
index 50f20d107..f9fd0017b 100644
--- a/doc/7-systems/ym2610b.md
+++ b/doc/7-systems/ym2610b.md
@@ -120,6 +120,12 @@ SSG-EG is short for "Software-controlled Sound Generator – Envelope Generator"
 
 a full guide to SSG-EG is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU), this [detailed technical explanation](https://gendev.spritesmind.net/forum/viewtopic.php?t=386&start=106), and this [chart of tunings](https://docs.google.com/spreadsheets/d/1HGKQ08CnLGAjA1U0StJFldod3FkQ3uq86rYy1VBIuZc/).
 
+## CSM
+
+CSM, or "Composite Sine Mode", involves a timer matching the frequency of the note in the "CSM Timer" channel. each time it triggers, it generates key-on and key-off commands to reset the phase of all operators on channel 3 and force their envelopes to restart at the release point. this can be used to create vocal formants (speech synthesis!) or other complex effects. outside this chip's specific implementation, the technique is known as "oscillator sync".
+
+working with CSM is beyond the scope of this documentation. for more information, see this [brief SSG-EG and CSM video tutorial](https://www.youtube.com/watch?v=IKOR0TUlnWU).
+
 ## chip config
 
 the following options are available in the Chip Manager window:
diff --git a/doc/8-advanced/find-find.png b/doc/8-advanced/find-find.png
index 69889f360..34d05ed52 100644
Binary files a/doc/8-advanced/find-find.png and b/doc/8-advanced/find-find.png differ