Apple Logic Express 9 - Manual (Page 1182)

• Pop/Jazz (3/5/7-all): 5ths, 3rds, and 7ths are changed in this mode. It is great for Pop
and Jazz styles, especially when using sustained chords. It is less suitable for
polyphonic music, as the detuning of the natural 7th is significant. This mode should
always be used with a Depth of 90% or 100%, as other values will render the natural
7th acoustically ineffective.
• Baroque (3/5-adaptive): This mode tunes pure 5ths and 3rds (with changing
characteristics). In tonal music, with a clear harmonic center, the middle chords are
tuned very purely, whereas more distant chords are tuned with less purity. If the
harmonic center becomes unclear, all chords are tuned with equal purity. As with
the other mode parameters, a Depth value of 100% determines the highest purity,
and a value of 10%, the lowest purity.
• Hermode Tuning: Depth slider: Allows you to set degrees of effect between 0% and
100%.
About Tuning
The following sections provide some background information about tuning.
About Alternate Tunings
The 12 tone scale used in Western music is a development that took centuries. Hidden
in between those 12 notes are a number of other microtones—different frequency
intervals between tones.
To explain, by looking at the harmonic series: Imagine that you have a starting (or
fundamental) frequency of 100 Hz (100 vibrations per second). The first harmonic is double
that, or 200 Hz. The second harmonic is found at 300 Hz, the third at 400 Hz, and so on.
Musically speaking, when the frequency doubles, pitch increases by exactly one octave
(in the 12 tone system). The second harmonic (300 Hz) is exactly one octave—and a pure
fifth—higher than the fundamental frequency (100 Hz).
From this, you could assume that tuning an instrument so that each fifth is pure would
be the way to go. In doing so, you would expect a perfectly tuned scale, as you worked
your way from C through to the C above or below.
To simplify this example: Imagine that you are tuning an instrument, beginning with a
note called C at a frequency of 100 Hz. (A real C would be closer to 130 Hz.) The first fifth
would be tuned by adjusting the pitch until a completely clear tone was produced, with
no beats. (Beats are cyclic modulations in the tone.) This would result in a G at exactly
150 Hz, and is derived from the following calculation:
• The fundamental (100 Hz) x 3 (= 300 Hz for the second harmonic).
• Divided by 2 (to drop it back into the same octave as your starting pitch).
This frequency relationship is often expressed as a ratio of 3:2.
1182 Chapter 42 Project Settings in Logic Express