ALICE AIR 2000 User Manual

AIR 2000 Broadcast Console
User Manual
THE CONCEPT
The ALICE AIR 2000 Broadcast console is designed specifically for rigorous use by professional broadcasters. Over
three years of research and development, together with extensive consultation with engineers and presenters at
many radio stations world-wide, have resulted in numerous features not normally available without expensive
customisation, or external 'black boxes'.
The AIR 2000 has been designed to require minimum maintenance and to provide excellent reliability for many years
of hard service. All component parts have been carefully selected to ensure that their life expectancy is no less than
that appropriate for the job. Only high-quality conductive plastic faders are used. High quality VCA's remove audio
signals from channel faders maximising their life, eliminating 'scratching' and ensuring tight stereo tracking.
Headphone and speaker controls, normally notorious for early failure, employ the same VCA technology, together
with DC control derived from paralleled potentiometers for maximum reliability.
All ICs are fitted in gold plated, turned pin holders for ease of servicing and reliable contact. Two-part, gold plated
locking, module connectors eliminate unreliable edge connectors. All illumination is achieved by high brightness LED
clusters, eliminating bulb failures. Large heavy duty, high quality switches are provided for main functions.
A blank sheet approach to circuit design has resulted in many innovative circuitry developments, which extensively
overcome previous shortcomings in commonly used circuit configurations.
A totally new electronic floating balanced output stage gives a 'ruler flat' frequency response and a full 28dB wide
band headroom performance unbeaten by even the best transformer-based outputs. This proprietary design
achieves an output impedance of less than 1 ohm, uniquely guaranteeing constant output level into balanced or
unbalanced loads, irrespective of their impedance. In comparison, a typical 75-ohm output would suffer a gain error
of over 1 dB and commonly also results in changes to the frequency response when the load is changed from high
impedance bridging to 600 ohms.
Many active balanced outputs do not allow unbalanced connection without causing considerable gain error and/or
gross distortion and in some cases may even damage the shorted output driver. Others which attempt to overcome
these problems are prone to instability when driving long lines, still give unbalanced gain errors of around 0.2dB and
rely on sensitive adjustment pots to achieve acceptable output balance. Naturally, these tend to drift with time and
result in additional maintenance work for the already overstretched engineer. With no fewer than 8 balanced output
stages on the main output module and others on insert points and telephone sends, the total elimination of output
balance adjustment pots is a major advantage. A unique pan pot design ensures perfect centre balance and provides
25-3OdB better final attenuation than conventional designs.
New level control and EQ circuitry utilising centre-tapped pots and zero impedance buffers forces predictable
performance, irrespective of pot tolerances, ensuring outstanding stereo tracking.
Mix busses are differentially balanced for improved crosstalk performance, rejection of unwanted interference and
ground loops. Totally silent solid-state audio switching completely removes inactive input channels from the mix-
busses, preventing unnecessary build-up of mix noise and providing virtually unmeasurable inter-channel crosstalk.
1
©Alice Ltd 2019 t/a Alice Soundtech™ Rev 5.0