added some comments

edrumulus.cpp

@@ -1505,6 +1505,7 @@ void Edrumulus::Pad::process_control_sample ( const int* input,
   // Detect pedal stomp --------------------------------------------------------
   update_fifo ( cur_midi_ctrl_value, ctrl_history_len, ctrl_hist );
 
+  // to cope with ADC noise, we use a moving average filter for noise reduction
   float prev_ctrl_average = 0.0f;
   float cur_ctrl_average  = 0.0f;
   for ( int i = 0; i < ctrl_history_len_half; i++ )

edrumulus.h

@@ -327,7 +327,7 @@ class Edrumulus
       void sched_init() { init_delay_cnt = init_delay_value; }; // schedule initialization function (for delayed initialization)
       const float      init_delay_value_s = 0.2; // init delay value in seconds
       static const int length_ampmap      = 20;  // maxmimum number of amplification mappings for clipping compensation
-      static const int ctrl_history_len   = 10;  // (MUST BE AN EVEN VALUE) control history length, use a fixed value
+      static const int ctrl_history_len   = 10;  // (MUST BE AN EVEN VALUE) control history length; the longer, the more noise reduction but more delay
 
       // band-pass filter coefficients (they are constant and must not be changed)
       const int   bp_filt_len           = 5;