Solidyne 542 APC, Owner'S Manual

Page: 31 / 44

Section 4 Audio processing
The audio processing stages are accessed in the SETUP
screen, from the PROCESS menu option.
The different processing stages are shown grouped in
tabs. From left to right, the order in which the processes
appear corresponds to the actual interconnection order
of the stages, with the exception of WIZARD which is not
a processing stage in itself.
1. WIZARDS
2. ENHANCERS
3. ENHANCER EQ
4. AGC
5. MULTIBAND AGC
6. MULTIBAND LIMITER
7. MIX & CLIPER – FINAL LIMITER
4.1 WIZARD
The WIZARD controls work on user presets. They allow
the user to quickly change the character of the sound
and create new presets (see below) without the need to
individually modify each stage of processing. No ad-
vanced knowledge is required to use these controls. Any
user can customize the sound of the station.
Advanced users looking for a more specific and precise
adjustment of the sound, will be able to modify the differ-
ent stages of the processor at their discretion.
The wizard controls allows:
1. Change the character of a preset in four essen-
tial ways: BASS - BRIGHT - COMPRESSION -
LOUDNESS.
2. Switch on/off and basic settings for the EN-
HANCERS: VOICE SYMMETRIZER, EQ, BASS EN-
HANCER, STEREO ENHANCER.
Each WIZARD control changes different parameters of
the processing stages simultaneously and syn-
chronously, to achieve the desired setting. The four con-
trols BASS, BRIGHT, COMPRESSION, and LOUDNESS are
interrelated as some parameters are affected by more
than one control. For this reason, when a control is
moved, the position of all Wizard controls is recalcu-
lated.
When a preset is loaded, the WIZARD controls are posi-
tioned according to the current preset settings. Viewing
the position of the WIZARD controls gives an idea of the
sonic characteristics of the presets, allowing a quick
comparison.

Although they have a wide range of action, it is a good
idea to use the WIZARD controls to apply moderate
changes to a preset. Always start from the preset that
is closest to the desired characteristics.
For example: if you are looking for a high-loudness pro-
cessing, it is not a good idea to start with a soft preset
(SOFT PROCESS) and take the WIZARD LOUDNESS
control to the maximum. It will be convenient to start
with a MaxLoudness setting, since it is already de-
signed to obtain maximum loudness (the interaction
between the different stages is optimized).
4.2 Enhancers
4.2.1 Voice symmetrizer
It’s a known fact that, by a particular arrangement of the
vocal cords, the sound emission of human voice are asym-
metric triangular pulses. The three cavities that filter and
form these formants, to obtain the vocal sounds, do not
modify this intrinsic characteristic of the human voice. The
whole word spoken and still sung is strongly asymmetri-
cal. This creates a significant reduction in the energy of
the audio signal, particularly when passing through a com-
pressor. This is because a compressor adjusts its com-
pression level to the highest peak, regardless of its polar-
ity. In this way when a polarity is set at 100%, the opposite
polarity hardly exceeds 50%, due to the asymmetry.
It is a known phenomenon that music tends to sound
stronger than the human voice, after passing through a
compressor. This is because the musical sounds are sym-
metrical, while the human voice is not. To correct this
anomaly WITHOUT INTRODUCING ANY CHANGE IN
SOUND QUALITY, peak symmetrizers are used.
This technique, based on a discovery by Dr. Kahn, acquires
international validity with Eng. Bonello's work, particularly
that published in the Journal of AES, Vol. 24, which de-
scribes, for the first time, the theory of Its operation.
4.2.2 Expander
The object of the expander is to improve the signal-to-
noise ratio in the air. Multiband compression, while in-
creasing loudness, reduces the S / R ratio. This effect
would be annoying because, if not for the action of the
expander could be heard the floor of noise in prolonged
pauses that normally are generated with the word. The
threshold is the point at which the expander begins to re-
Audio Processing Core - SOLIDYNE 542 APC Page 31