diff --git a/src/expression_pedal.cpp b/src/expression_pedal.cpp
index 5feceac..b86843d 100644
--- a/src/expression_pedal.cpp
+++ b/src/expression_pedal.cpp
@@ -10,8 +10,8 @@ ExpressionPedal::ExpressionPedal(uint8_t adc_pin)
     , midi_cc(4)
     , last_read_time(0)
     , current_raw(0)
-    , cal_min(0)
-    , cal_max(4095)
+    , cal_min(36)
+    , cal_max(1239)
 {
 }