diff --git a/packages/superdough/README.md b/packages/superdough/README.md
index 7c199deb..f32aa32d 100644
--- a/packages/superdough/README.md
+++ b/packages/superdough/README.md
@@ -68,7 +68,9 @@ superdough({ s: 'bd', delay: 0.5 }, 0, 1);
   - `shape`: distortion effect from 0 (none) to 1 (full). might get loud!
   - `pan`: stereo panning from 0 (left) to 1 (right)
   - `phaser`: sets the speed of the modulation
-  - `phaserdepth`
+  - `phaserdepth`: the amount the signal is affected by the phaser effect.
+  - `phasersweep`: the frequency sweep range of the lfo for the phaser effect.
+  - `phasercenter`: the amount the signal is affected by the phaser effect.
   - `vowel`: vowel filter. possible values: "a", "e", "i", "o", "u"
   - `delay`: delay mix
   - `delayfeedback`: delay feedback