Update README.md

1 files changed, 1 insertions, 1 deletions

diff --git a/README.md b/README.md
index 938a605..f682938 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ To use simply create a `PSG49` object as follows:
 ```
 var emu8910 = new PSG49(YM_CLOCK_ZX, 50);
 ```
-Which sets the default clock speed and interrupt frequency (50 Hz). 
+Which sets the default clock speed and interrupt frequency (`50 Hz`). 
 
 This exposes a a `PSG` register file in the `emu8910.register` object:
 ```