diff --git a/libaf/equalizer.h b/libaf/equalizer.h
new file mode 100644
index 0000000000..ee5ee6eadd
--- /dev/null
+++ b/libaf/equalizer.h
@@ -0,0 +1,33 @@
+/*=============================================================================
+//	
+//  This software has been released under the terms of the GNU Public
+//  license. See http://www.gnu.org/copyleft/gpl.html for details.
+//
+//  Copyright 2002 Anders Johansson ajh@atri.curtin.edu.au
+//
+//=============================================================================
+*/
+
+/* Equalizer plugin header file defines struct used for setting or
+   getting the gain of a specific channel and frequency */
+
+typedef struct equalizer_s
+{
+  float gain;   	// Gain in dB  -15 - 15 
+  int	channel; 	// Channel number 0 - 5 
+  int 	band;		// Frequency band 0 - 9
+}equalizer_t;
+
+/* The different frequency bands are:
+nr.    	center frequency
+0  	31.25 Hz
+1 	62.50 Hz
+2	125.0 Hz
+3	250.0 Hz
+4	500.0 Hz
+5	1.000 kHz
+6	2.000 kHz
+7	4.000 kHz
+8	8.000 kHz
+9       16.00 kHz
+*/