Symetrix 601, Owner'S Manual

Page: 127 / 142

E-1
Rev 2.2, 10/31/94
E. Architect’s and Engineer’s Specification
The integrated signal processor (ISP) shall be a single input, dual output model capable of
simultaneously accepting a microphone-level or line-level signal , applying frequency response
equalization, delay-based effects, and signal dynamics processing to that signal, and delivering
the processed input signal to two outputs. All signal processing (equalization, delay, dynamics)
shall take place in the digital domain. The ISP shall occupy one rack space (1U).
The equalizer block shall take the form of a user and MIDI programmable parametric equalizer
capable of operating at three inflection points simultaneously. Band 1 of the equalizer shall be
switchable between a lowpass shelving characteristic or a peak/dip characteristic. Band 3 of
the equalizer shall be switchable between a highpass shelving characteristic or a peak/dip
characteristic. All three bands of the equalizer shall be capable of operating over the following
frequency ranges and bandwidths:
31 to 21.11 kHz with a bandwidth of .05 to 3 octaves, with a boost/cut range of +15 dB
to -50 dB.
The delay block shall provide two delays capable of up to 330 milliseconds of delay. The delays
shall be user and MIDI programmable. The feedback path for delay recirculation shall be cross-
coupled between the two delays and the delay time shall be capable of accepting modulation
either from an internal random number generator or from an internal sine- or triangle-wave
source. The delay time shall be independently adjustable for each delay and provision shall be
made to allow adjusting the delay times simultaneously while maintaining an offset in the delay
times.
The dynamics block shall provide the following functionality: De-ess, Dynamic noise filter,
Compressor, AGC/Leveler and Downward Expander. Within the dynamics block all sections are
user and MIDI programmable and each dynamics function shall provide the following features:
De-Ess High-ratio compression driven by a high-frequency
selective sidechain. The de-esser shall provide a threshold
control for user adjustment.
Dynamic Noise Filter Sliding high-frequency rolloff controlled by the HF energy
content of the input signal. The DNF shall provide
threshold and frequency controls.
Compressor Compression up to 10:1 ratio. The compressor shall
provide threshold, ratio, attack, and release controls. The
compressor characteristic shall be changeable between a
hard-knee curve and a soft-knee curve.
AGC/Leveler AGC over a 70 dB range, with adjustable gain platform
and up to 4:1 ratio. AGC shall provide auto-release
threshold, ratio, attack, and release controls.
Downward Expander Downward expansion with up to 1:8 ratio. Expander shall
provide threshold, ratio, attack and release controls.
The output block shall provide level and panning for the output signal. Both functions are user
or MIDI programmable. The level control shall operate in the digital domain over a +/- 18 dB
range. The panpot shall also operate in the digital domain with a sine-cosine characteristic law.
The ISP shall provide easy access to all user functions via a non-hierarchical parameter
selection and modification scheme. There shall be a minimum of menus. Every major
parameter shall be accessible via a button-press and subsequent adjustment of the parameter
wheel.