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SONIFEX RB-SSML1 CONTRIBUTION UNIT Microphone / line in, compressor limiter, headphone feed

Stock code
Model number
  • RB-SSML1
SONIFEX RB-SSML1 CONTRIBUTION UNIT Microphone / line in, compressor limiter, headphone feed


Intended for use in voice-over booths, news and commentary booths, these contribution units offer a microphone input, as well as a headphone amplifier for cue and programme signals.

RB-SSML1 - Mic/Line Source Selector with Compressor/Limiter

Either the microphone or the line input can be switched, by the operator, to feed the main output, with or without compression. This is used to feed a contribution circuit, of some kind, back to a studio or control room, or perhaps to recording equipment or a PC. The output is also fed internally to the stereo 'headphone' mix. A stereo external monitor input can be fed with a cue/monitor signal from a return circuit, or perhaps an off- air tuner or a PC sound card. This feeds the headphone mix only; it does not feed to the main output.

On the front panel there are two volume controls for microphone and line inputs, a button to select between microphone and line, and a compress/bypass switch for the stereo compressor-limiter. This has knobs to set threshold and compression. Two horizontal rows of twelve LEDs may be configured to show either the stereo output level or the level of the headphone mix. A volume control is positioned adjacent to the two 6.35mm, A-gauge, stereo headphone sockets, controlling the level at both sockets.

On the rear a pair of electronically balanced outputs are provided using 3-pin male XLR connectors. These may be connected to unbalanced systems without loss of level and have an associated switch to set nominal output level to 0dBu or -10dBu. The electronically balanced line inputs use a pair of male 3-pin XLR connectors which have an adjacent switch to set nominal input level to 0dBu or -10dBu. The microphone input is another 3-pin XLR connector. A screwdriver-preset sets gain. A block of four miniature switches enable 48V phantom powering and the low-cut filter for the microphone, set the compressor to compress the microphone signal only, disable the peak-hold function of the meters. A further pair of male 3-pin XLR connectors are used for the electronically balanced line-level monitor inputs, which also have an adjacent switch to set nominal input level to 0dBu or -10dBu and a screwdriver preset to adjust the proportion of the return monitor signal in the headphone mix. Power is connected to an IEC inlet, with adjacent fuse and voltage selection switch.

Input: -10/+28dBu mic/line maximum, 20kohm, nominal, balanced. Common mode rejection: greater than 66dB. Gain range: 36-75dB microphone, -80dB with volume at minimum. Line volume range: -80dB to +6/+16dB. Response: 20Hz to 20kHz +/-0.3dB. Low frequency roll-off: 125Hz, 6dB/octave. Distortion: 0.02% THD, 1kHz, +8dBu output. Noise: -130dB EIN. Output: +28dBu maximum, 50 ohms. Power source: 110-120V or 220-240V AC 9W maximum. Dimensions: 480(w) x 108(d) x 42(h) mm. Weight: 1.3kg.

Included accessories: Handbook, AC power cordset with plug.
Optional accessories: RB-RK3 rear panel rack kit.

RB-MTV1 – Contribution and voiceover unit – with talkback

Built in a 1U high, rack-mounting case, the device offers a single microphone channel, routing to a talkback output, two main outputs, for studio and local recorder, say, and the monitor system. The incoming cue and programme inputs are stereo. They could be used, for example, for an off-air feed and remote studio output. The talkback input is mono, and might come from a remote studio talkback system.

The front panel has two large illuminated switches, 'talk' and 'mic', for routing the signal to the 'talk' ('lazy') output, for use as a return talkback feed to another studio, and the main outputs respectively. When the 'talk' function is active, the microphone signal on the main outputs is muted. The 'talk' function is available even if the 'mic' function is inactive. Between the two switches is an LED to show when the microphone limiter is in action, and a five stage LED bar-graph. This may be configured to show the level of the microphone signal prior to the switching or only when the signal is connected to the main outputs. Four rotary controls adjust the mix of the microphone, talkback, cue and programme signals to the headphone amplifiers, routed as determined by a matrix controlled by two banks of DIP switches on the underside of the unit. It is possible to route the microphone, talkback, cue left and right, programme left and right signals into neither, either or both earpieces of the headphones. A 6.35 mm jack socket provides the headphone connection, wired in parallel with a similar connector on the rear.

The rear panel has a headphone socket, two male XLR connectors providing the main outputs, each with an adjacent switch to choose either microphone or line level, a male XLR for the 'lazy' output, and five female XLR connectors for the mono talkback and stereo cue and programme inputs. The pairs of cue and programme connectors each have a single switch to increase the gain of the signals by 10dB, so that unbalanced sources may be used. The remaining XLR provides the microphone input, and has an associated switch to activate the limiter, while two multi-turn screwdriver operated controls adjust gain and limiter threshold. All XLR connections are balanced. A 9-pin female D-sub connector offers access to the remote control of the 'mic' and 'talk' functions, and opto-isolated indicator outputs for each. A bank of DIP switches enable the phantom powering, low-cut filter, and extra 20dB microphone gain, as well as the option to mute the microphone signal to the headphones when the 'talk' function is activated. A filtered IEC inlet, with adjacent fuse, provides the power connection.

Microphone input: -10dBu maximum, 2kohms. Phantom power: 48V Common mode rejection: Better than 60dB, typically. Microphone gain: +20dB to +80dB, adjustable. Noise: -130dB E.I.N. Distortion: 0.01% THD, 1kHz, +8dBu output. Low frequency filter: 125Hz, 6dB/octave. Other inputs: +26dBu maximum, 20kohms. Limiter threshold: +8dBu to +26dBu, adjustable. Maximum output: +26dBu, less than 50 ohms, for balanced outputs. Headphone output: 150mW into 32-600 ohms. Response: 20Hz-20KHz +/- 0.1dB, 1kHz. Power source: 110V-120V or 220-240V AC, switchable, 9W maximum. Dimensions: 1U rack mounting, 108mm deep. Weight: 1.3kg.

Included accessories: Handbook, AC power cordset with plug.
Optional accessories: RB-RK3 rear panel rack kit.

  Description Price £
ex. VAT
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SONIFEX RB-SSML1 CONTRIBUTION UNIT Microphone / line in, compressor limiter, headphone feed Stock code: 95-622
No longer manufactured. Please contact Technical Support for advice on alternatives.
SONIFEX RB-MTV1 VOICEOVER CONTRIBUTION UNIT Microphone, headphone amplifier, monitor mixer Stock code: 95-685
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SONIFEX RB-RK3 RACKMOUNT KIT Rear panel - reverse mount, for 480mm wide types Stock code: 95-639
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