+#!/bin/sh
+#Example of guitar tuner using goertzel:
+#165Hz = Low E
+#How to tune:
+#There are 3 frequencies, you have to make the middle one (target frequency) most loud
+#and the other two surrounding it shoud show approximately same intensity
+
+arecord -r 44100 | ./goertzel -r 44100 -f 150 -f 165 -f 180 | ./histogram.pl