Making a live set-up sound good may have as much to do with your ears as it does with the room.
We have 2 all heard feedback at one time or another, but did we know what frequency was ringing? I’m sure almost all guitarists know that the A above middle C is 440Hz, but not everyone knows what frequency the next A going up the scale is. You guessed it, 880 Hz. With a little experimenting and some simple math, I’m sure most people will be able to guess at least in the ballpark of what frequency is sounding off. For those sound engineers who think they have perfect pitch (if that exists), here’s a way to find the frequency of a specific note: Multiplying the frequency of any known note (ie: A 440 Hz) by 1.059546 will give you the frequency of the next note up the scale (A# 466.2 Hz). Here’s the point to all this – getting to know your frequencies just by hearing them will take some of the guess work out of your EQing. Use any instrument you can get your hands on to give you sound to experiment with (even if it is controlled feedback). I’ve included the math as it might answer some of those questions you thought were too stupid to ask. By the way … what is a one-third octave EQ anyway?
Rob Patterson – freelance sound engineer and MIDI programmer, Toronto, ON