So if our hearing works within these 10 octaves, where does 1/3 octave come into play? Why 30 bands? Well,
through extensive research at the world famous Huh! Earology Institute, Dr. Koneairea determined that 3 dB
changes between 1/3 octaves are the smallest changes the human ear can easily detect. His lab assistant Mongo
agreed that 30 bands was best since that was the maximum number of dials he could draw on the chalk board. So
30 bands it was.
Seriously though, the Kicker KQ30 is a 30 band, 1/3 octave equalizer designed for tailoring your sound system to
better fit your listening environment (your car we hope) or to just make it sound like you want it to sound.
Through experimentation it has been shown that the way the human ear sums energy in the Critical Bands to
determine the loudness of a sound are about one third octave apart. Because of this, one third octave spacing is all
that is required to tune a system within the capabilities of the average human ear. You could use an equalizer with
tighter spacing (like a 1/6 octave) but this would only present you with twice as many dials to adjust (60+...Ouch!)
and no better audible results than a finely tuned 1/3 octave unit. In other words, a lot more work for no audible
benefit. Even the ‘Super Tweaks’ at Kicker who just love to play with buttons, switches and dials agree that 1/3
octave is the way to go!
The chart below gives you a good idea where some of the musical instruments and voices operate within the 1/3
octave scale. The Fundamental Frequencies are the primary sounds the instrument makes when played. The
Harmonics or Overtones are multiples of the Fundamental sound. Think of it like striking a hollow drum. When you
hit the drum it makes a distinct sound, but there are also extra sounds that reverberate from the original strike.
These extra sounds are Harmonics. These Harmonics plus the Fundamental give every instrument, voice or sound
it’s own unique sound.
Introduction
20 40 63 100 156 250 400 635 1K 1.6K 2.5K 4K 6.4K 10K 16K
31.5 50 80 126 200 320 500 800 1.27K 2K 3.2K 5K 8K 12.8K 20K
Kick Drum
Snare Drum
Cymbals
Chimes
Bass Guitar
Lead Guitar
Female Vocal
Male Vocal
Saxaphone
Organ
Piano
String Bass
Violin
Cello
Clarinet
Flute
Trumpet
Cat Howling
James Brown
Fundamental Frequency
Harmonic or Overtone
1/3 Octave Frequency Spectrum
KQ30 Equalizer Technical Manual
Version 1.0
January 1, 2002 Page 3
