Article 4 - Taming of the Feedback Beast

Written and copyrighted 03/11/1999 - by Bob "Hoochie Coochie" Paolucci

Bob "Hoochie Coochie" PaolucciFeedback. The enemy of all harmonica players. We all know it. It's that piercing, sustained high frequency squeal that our amplifiers pour out when they are in one of their moods. Well, it's not our fault, right? Positive feedback occurs whenever a microphone is placed in a position to "hear" the speaker of an amplifier. This signal is "fed back" into the system and, if loud enough, will sustain itself, getting ever louder and louder until the entire bar is cringing and saying "thank you" (that's not really what they are saying). The "natural" frequency of the squeal is determined by the time delay of getting the sound from the microphone to the speaker through the air (feedback loop) back to the microphone.

Feedback by itself is not a bad thing. In fact, it's what gives some guitar amps their singing sustain and can be a much sought after attribute of the amp. Guitars, however, use pickups, not microphones as input devices and are therefore not as sensitive to feedback loops as a microphone is.

Getting rid of feedback is a major problem for a harmonica player and can be quite difficult to do, especially with a loud band. Feedback is affected by many things and consequently there are no hard and fast rules for eliminating it. The size and shape of the room, number of people in the room, amplifier settings, equipment and microphone placements are only a few of the elements that can allow feedback to occur. Knowing what these elements are can help us avoid certain conditions or compensate for them. Here are a few things that may help out: 

Well, one last but always important thing. YOU ARE THE KEEPER OF YOUR TONE. Ultimately, you control the vertical, you control the horizontal, you control the feedback. We all feedback from time to time, but by using the knowledge I've just shared with you, I've been able to eliminate the worst of my feedback problems and you should be able to as well. As always, if you have any questions or comments you can email me.