Use This Handy Chart of Note Frequencies and Instruments to Eliminate Background Noise From Your Mix
This article originally appeared on CD Baby's DIY Musician blog, and was written by Alex Andrews of Ten Kettles Inc. .
What's the frequency of C, and why should you care?
It's 261.6 Hz. Why would we ever need to know this? Well, there could be a few different reasons, but one has to do with mixing audio. When equalizing (EQing) an audio track, one common challenge is filtering out background noise – especially if the track was recorded with a microphone. Here's what the mic might be picking up:
The rumble of a streetcar or truck going by in the distance
An accidental knock of the microphone stand
A door closing somewhere in your building
Your best route to eliminating background noise is to cut it out at the source, but in many cases (barring time travel) that's just not possible. So we use an equalizer, or EQ, to lend a helping hand.
Take a guitar track, for example. What's the lowest sound you'd expect to come from a guitar? If it's in standard tuning, the lowest string is tuned to E2, which has a frequency of 82.4 Hz (see the table below). This means that any sound below ~80 Hz is not guitar. So, if we filter out everything below that frequency, we cut out the low noise (like the streetcar rumble) but keep all that great guitar sound. Not bad! The name for this kind of filter is a high-pass filter, because it lets all the high frequencies pass, and keeps out the low ones.
Below is a table of all the note frequencies, with the highest and lowest notes of various instruments highlighted. The first column is the octave number. For example, the low E string on a guitar is tuned to E2 – that’s E in the second octave.
E20.60Approximate lower limit of human hearing (increases with age)
B30.87Lowest note of a 5-string bass
E41.20Lowest note of a 4-string bass
E82.41Lowest note of a guitar
G98.00Approximate low-end of male vocals (depends greatly on individual)
G196.0Approximate low-end of female vocals (depends greatly on individual)
D♯/E♭311.1Highest note of a 4 or 5-string bass
G392.0Approximate high-end of male vocals (depends greatly on individual)
G784.0Approximate high-end of female vocals (depends greatly on individual)
6C1047Highest note of a 20-fret guitar
D♯/E♭19,912Approximate upper limit of human hearing (decreases with age)