Friday, November 15, 2013

JND Bends


Over a tuning drone, try bending the pitch just the smallest amount.

For that matter, try it during your long tones.  The goal: sensitize your ears!

Play a little tune and purposely play a note just a hair sharp or flat.  Can you hear it?  Play around with it.

Don't get wrapped up in right or wrong....just listen.  Zoom in with your ears.  Hear the smallest things.

In psychology I think we would be dealing with Weber's Law which states:

The Difference Threshold (or "Just Noticeable Difference") is the minimum amount by which stimulus intensity must be changed in order to produce a noticeable variation in sensory experience.
Someone can correct me on this but I think the above formula explains why a frequency change of a music half step smaller on lower notes.
For example:
From C1 to C#1: 34.65 - 32.70 = 1.95
From C4 to C#4: 277.18 - 261.63 = 15.55

Our ears hear the change of 1.95 and 15.55 as a half step because the frequency is higher.  The ratio stays the same.

OK, that's a little too much math for a trombone player.  What does this boil down to? Sometimes our worries about being out of tune actually get in the way of clarity.  By playing around with the pitch in a non-judgmental way, we gently allow our ears to become more sensitive.

I call these "JND Bends."  Try them out.  See how small a pitch change your ears can notice.  You might be surprised.