AEV Xtreme II Digital Audio Processor
AEV Broadcast Srl – via della Tecnica 33 – 40050 Argelato (BO) Italy
Web site www.aev.eu e-mail [email protected]
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Sec. 1 The Xtreme audio processor
The Audio Xtreme II processor is a complete audio signal processing system for AM, FM and TV transmissions.
The sound quality defines the station’s image and professionalism. The importance of the AUDIO PROCESSOR
is therefore clear. The wholly digital technology with which Xtreme II was built means that the results obtained
can IN NO WAY BE COMPARED with those of any other traditional processor.
The multi-band structure is the best way to process an audio signal; Xtreme II is based on five-band processing
of the audio signal, with a storage capacity equal to 82 different equalization curves, 64 of them editable.
Every curve has the facility for integral control of process parameters to give your station a competitive sound,
with extra power, continuity, presence and clarity, without “pumping” or other unnatural effects.
All of Xtreme II’s adjustments and operational sequences are distinctly shown on a high resolution LCD graphic
display and are facilitated by a guided menu showing the enabled functions at every programming step.
The equalization and compression curve trends are shown on the display, which graphically reproduces the
spectral distribution of the processed signal over 5 bars.
Sec. 1-1 Full control of peak modulation
Xtreme II provides full control of AM, FM and TV audio signal transmission levels and can interface with any
transmitter habitually used in any part of the world.
Xtreme II performs a high-precision peak control, restricting over-modulation level to just 0.3 dB !
The Xtreme II audio processor dynamically controls the pre-boost level, it can never be heard to operate, and
produces a clear, open, brilliant sound which improves the original program.
Xtreme II’s audio processing circuits produce a signal which is pre-boosted with 50
µ
s or 75
µ
s curves and is
controlled precisely and absolutely in order to avoid over-modulation; the signal is then filtered to protect the pilot
tone at 19 KHz. If the 2-channel signal output by the processor is inserted in an external stereo encoder, we
advise you not to place any element between the two appliances that could alter band width and enlarge
modulation peaks beyond average modulation levels. Otherwise, modulation level must be reduced to control the
highest peaks.
Low-pass filters, high-pass filters, transformers, distribution amplifiers, and long transmission lines, can all cause
the signal to alter. We advise you to by-pass any low-pass filter and pre-booster circuits present on normal stereo
coders; we should stress that these measures have already been adopted inside the processor.
Obviously the above criteria for optimal control of peak modulation levels can be satisfied more easily if the audio
processor uses the internal stereo encoder. In Xtreme, there are no circuit elements between the audio processor
and the internal stereo encoder that could cause wave shape distortions. We therefore advise you to use Xtreme
with its own builtin encoder whenever feasible.
Sec. 1-2 Programmability
Xtreme II is supplied with 18 program-resident equalisation curves; they help the user understand the
programming process. The remaining 64 curves are at the user’s disposal.
For specific programming operations, see the appropriate paragraph.
All programming operations can easily be directly retrieved by the operator, by using the “Jog” knob or by using
the “Planning” programming at exactly specified times.
Sec. 1-3 Input/output configurations
Xtreme II was designed to house the following simultaneously:
1. left/right analogue inputs and outputs
2. Standard AES EBU digital inputs and outputs
3. 2 composite stereo outputs (for FM version)
4. RDS input (if RDS coder option is not installed)
5. SCA input (for FM version)
6. RDS output (if RDS coder option is installed)