SILVER Audio Processor 4Bmini User’s manual
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Audemat-Aztec SA – Audemat-Aztec INC
web: www.audemat-aztec.com - e-mail: [email protected]
The SILVER Audio Processor 4Bmini and Its Processing
Structure
The SILVER Audio Processor 4Bmini broadcast audio processor is intended to be used for processing audio prior to
broadcast on FM.
Before we discuss the processing structure in full we would like to tell you a little about the final peak limiting stage of
the SILVER Audio Processor 4Bmini. It employs distortion controlled clippers to limit the peaks of the signal.
Distortion controlled clipping is the best method for preserving as much high frequency energy as possible, important
when the high frequency loss characteristics of the FM broadcast de-emphasis curve is taking into account. Distortion
controlled clipping produces harmonic distortion which if used moderately can produce a sizzling bright sound but can
result in a ripping or tearing sound if used excessively (overdriven).
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Input selection and conditioning
The SILVER Audio Processor 4Bmini offers the user input selection (analog or digital input) and pre-emphasis
selection.
Bass enhancement
The SILVER Audio Processor 4Bmini offers a bass enhancement via peaking filter that can be set to provide up to
6dB of gain on one of four frequencies with a choice of 4 Q's. This can be thought of as a simple bass parametric.
Xover
The SILVER Audio Processor 4Bmini employs linear-phase time aligned digital FIR filtering to split the audio
spectrum into 4 bands while maintaining sonic transparency.
Multi-band AGC
The SILVER Audio Processor 4Bmini processes each band with RMS based levellers. Each bands gain control
processing function can be configured in different manners to provide different effects. Adjustable timing constants,
drive and gating afford the user with full control of this important re-equalisation stage of the processor.
Multi-band limiters
Each band has its own dynamic peak limiter. Multiple time constant based detectors are fully adjustable as well as
input drives.
Mixer
The four bands are 'virtually' mixed together at this stage, allowing overall EQ adjustment.
Bass clipper
The SILVER Audio Processor 4Bmini peak limits (clips) and linear phase filters the low frequencies before being fed
to the final clipper stages.
Distortion controlled clipper
The SILVER Audio Processor 4Bmini main clipper uses sophisticated algorithms to produce tightly peak controlled
output and maximum distortion control.
Stereo encoder
The SILVER Audio Processor 4Bmini's DSP stereo encoder takes its inputs after peak processing. The stereo
encoder is highly over-sampled and offers superb stereo performance. A composite clipping function is provided for
those who wish to use it.
