Crane Song IBIS - Manual (Page 3)

THE BASICS
The IBIS equalizer can do some very different things.
First, each band has 24 frequencies. 12 switch positions and a “+ one step button” this
button moves the frequencies up one whole musical step. The high and low bands also
can be shelving by pushing the shelving button.
The frequency chart showes how each of the bands over lap and how frequencies and
musical notes relate. As an example, with the +1 step button pushed in, the frequency
moves up two positions on the chart. 32.7 Hz which is the lowest frequency will become
36.7 Hz
There is a dead zone of about plus and minus .3 db on the “boost / cut” controls where the
EQ is flat in response. This allows an easy way to set your bands flat. The range is plus
or minus 12 db and is not stepped. The mastering version has a range of 6 db in .5 db
steps with a 1 db step between 5 and 6.
The Bandwidth is not stepped on the standard version and is steped on the mastering
version. the range is from 0.2 Oct to 4 Oct this is at 12 db of boost
The low cut is 12 db per octave, but the steep button increases the slope to 24 db per
octave.
The filters are of a special type that provide a very clean and smooth sound. To add
flexibility to the equalizer a color knob is inculuded.
The color knob is an additive second / third harmonic distortion type of process,
it can be applied to the full program or any one of the 4 bands. When doing a “cut” it will
subtract the harmonic content. The Color Knob is not stepped on the standard version
and is stepped on the mastering version
The use of the color function will allow you to change the equalizer from a very transparent
sound to a colored sound. Using it on the low frequencies, band 1, it will add warmth. On
band 3 it will add presence and some nice upper midrange detail. On the high frequency
band it will add air.