These are a range of audio 'input plates' which fit in a UK standard (BS1363/BS4662), 25mm deep, single or dual-gang, electrical back-box. Designed to increase the audio input capability of an induction loop system, they cover most common variants of audio connector as well as inbuilt microphone. When installed at the most convenient point of an installation. mounted on wall, ceiling and desk, they overcome the need for long and potentially hazardous microphone and audio leads.
Each plate has a built-in mixer, pre-amplifier, input level control and a balanced output. They work by mixing the signals from various audio input sources into one balanced line level signal which can then be fed into the line input, of a compatible amplifier. Typically, 'up to ten Outreach plates (any mix) can be daisy-chained to one balanced line level input with cable lengths of up to 100m easily achievable using standard two-pair audio cable with no recognisable degradation of audio signal quality.'
Two further plates are available, a 'Balanced Line Output Plate' to feed third-party audio equipment and the The 'Afils Active' indicator plate.
Each Outreach plate requires four wires; two balanced line (A +, A –), one ground (0V) and one power connection. Power source: 12 to 37V DC, regulated, 6 to 11mA. Many Signet AFILS loop amplifiers are fitted with an Outreach socket, but if the Outreach system is to be used with third party equipment which does not have a suitable DC power an external supply may be used, such as the APV Outreach plate, which is mounted in a dual-gang plate to fit UK standard back boxes, and requiring AC mains wiring, so should be installed by a suitably competent technician.
Specifications for the Outreach chain connections:
Line inputs: Balanced/unbalanced, 0.775Vrms (0dBu), 10kohms. Line outputs: Balanced, 0.775Vrms (0dBu) + 6dB (overload), less than 100 ohms. Response: 90Hz to 20kHz. Insertion loss/gain: Less than +/- 0.05dB. 'Insertion signal to noise ratio': '79dB THD + noise: 0.07%'.
Microphone Plates
APJ 3.5mm Microphone Jack Plate
Accepts 'unbalanced electret microphones with 3.5mm mono jack plugs. Includes an onboard mic to line level converter, high gain pre-amplifier and 8V phantom power'.
APQM 6.35mm (1/4 inch) Microphone Jack Plate
APXM XLR 3 Pin Microphone Plate
Accepts 'balanced or unbalanced microphones with standard 3 pin XLR connectors. Includes an on-board mic to line level converter, high gain pre-amplifier and 8V phantom power'.
APM Omni-Directional Plated Microphone
Accepts 'balanced or unbalanced electret microphones with 6.35mm (1/4 ") jack plugs. Includes an on-board mic to line level converter, high gain pre-amplifier and 8V phantom power'.
A 'self-contained omni-directional electret microphone complete with onboard mic to line level converter. Typical coverage up to 25m2 (ambient) or 2.5m (direct speech) when located at a ceiling height of 2.5-3m'.
Common specifications for microphone plates
Input signal level: -40dBu to -30dBu. Input gain control: 8 to 0dB. Input impedance: 500ohms. Phantom volts: 11V/0V (link selectable). Signal to noise ratio: better than 60dB. Distortion: Better than 0.07% THD + noise.
Line-Level Input Plates
APL Dual Phono Line Level Plate
Accepts 'stereo phono line-level signals (usually from a stereo source such as a TV). Includes an on-board stereo phono to mono converter'. This has two RCA (phono) inlet sockets.
APQL 6.35mm Line Level Plate
Accepts '6.35mm (1/4'') jack feeds from audio equipment such as stage or church mixing desks, etc.'
APXL XLR 3 Pin Line Level Plate
Accepts 'standard 3 pin XLR feeds from audio equipment such as stage or church mixing desks, etc.'
Common specifications for line input plates
Input signal level: -10dBu to +6dBu. Input gain control: 8 to 10dB. Input impedance: More than 1 kohm. Signal to noise ratio: Better than 71dB. Distortion: Better than 0.03%THD + noise.
Output plates
APXO XLR 3 Pin Balanced Line Output Plate
Provides 'an adjustable balanced line output (+12B max.) on a standard 3 pin male XLR connector. Typically used to connect an Outreach chain to third-party audio equipment such as conventional amplifiers.' Maximum XLR output signal level: +12dBu, balanced. Noise: -95dB. Output level control: 8to +12dB. Distortion: Better than 0.01%THD + noise.
API 'AFILS ACTIVE' PLATE
Includes 'two ultra-bright LEDs in a translucent diffuser overprinted with the AFILS 'ear' symbol. The LEDs illuminate when the Outreach network is powered to indicate that an AFILS system is installed.'