The Airmix On-Air radio mixer is D&R's solution for On-Air applications where features and functions has to be weighed up against operational simplicity. A simple direct accessible control surface combined with intelligent digital routing and a large number of PCB jumpers enables customizing to station requirements.

Purchasing choices offered by D&R are straightforward: the welded steel frame will accommodate a maximum of 16 triple input modules, which could include an unlimited number of Telco modules plus the master section with script space. Beyond this, options are limited to PPMs, a timer, and a triple input module with no equalization. The main outputs are transformer balanced and the majority of connectors are balanced XLRs.

The Triple Input Module

As the name suggests, the Airmix triple input module combines a mic input with two stereo line inputs. The A line input can be fitted with an RIAA plug-in PCB. There are Left and Right switches. which will sum a line input on the relevant input to both outputs. The fixed, to 12dB limited three-band equalization is followed by a stereo Aux control, which can be pre or post VCA/Mute, depending on a jumper. A Sub switch is routes signals to a separate output instead of the main outputs, allowing production work to be carried out during broadcasting. This is followed by a Pan control, peak LED, and a momentary Cue switch, post equalization and Pan. The channel On switch below disables Cue, although it can be reactivated while the channel is on. It is also possible to activate Cue via the channel remote connector. If this is done, Cue becomes a Cough facility when the Mic input is selected.

Faders are 100 mm and controlling VCA's. Start can be accomplished with the fader or the On switch, depending which is set first. Stop and Start can be configured so that switching from line A to line B stops one and starts the other. Similarly, the Timer jumper sends a pulse to the timer bus when a line input is selected and it is already On.

The DJ channel jumper dictates that when the channel is On a Cue is activated. the channel is in Mic mode and control room monitors are muted. Cue Announcer further extends the Cough facilityby activating Talkback from the engineer and Cue from the announcer with one switch when Telco modules are active. Reset is achieved With the Autocomm switch.

Line On Air determines whether one, both or none of the two line signals are connected to the line On Air signalling bus. Jumpers Mic on Air, line to Monitor, and Mic to Monitor are similarly self-explanatory.

The Dual Input Telco Module

The Telco Send level controls the outgoing signal to the caller. This is derived from the Mix or Sub bus, depending on the setting of the Sub switch on the telco module. The A/B switch determines which of two telephone lines is connected, while Gain controls its level. The Duck switch gives the announcer priority over the caller, while the HP and LP filters can be used to enhance intelligibility. Aux control is jumper select able pre or post. This is followed by the Sub switch, Pan, peak LED, and Cue Ring switch, with the On switch below it. Cue cannot be activated when the telco module is on. A flashing Cue Ring indicates an incoming call. Connecting a caller can be accomplished with the On switch when the fader is up or with the Cue switch when the fader is down.

When Cue is active in a Telco module, the caller is connected to the cue bus and also the engineers talkback, but does not go on-air as the fader is down. It is possible to connect both the Cue switch and an On Led to a remote, allowing a director to control the broadcast. There are only three types of jumpers for the Telco module. The OnAir 1/2 jumpers determine which of the two On-Air control busses is driven; Telco -to-Monitor jumper determines whether the Telco is connected to the monitor output. there is also a Timer jumper.

Centralized Master Section with Scriptspace

Situated beyond the script space, housed in the Master module, are five sections. The first section, Studio, selects the source for control room monitors (CRM), plus Guest and Announcer feeds. The Studio section is usually used to monitor the main output, with the ability to switch to From Air or From Sub. Send to Guest can be switched to follow CRM, if feed from the main output is not desired. The Announcer feed is provided with Follow CRM and Autocomm. The Tape section determines the feed to tape: Main Output, Sub or Oscillator. The Talkback section includes an individually controllable Director's Mic which can be assigned to Aux, Monitor, Guest. and Announcer outputs. The same options are available for the internal talkback mic. The Cue/CRM section enables the user to decide whether CRM follows Cue. It also includes Autocue Reset, which deactivates any active Cue on the desk. Below this are Dim level and additional Cue sources.

The Aux/Sub section controls the aux output and can also assign the sub mix to the main mix output. Below this is the Meter Follows CRM switch, which changes the meters from the normal configuration of left meter follows main mix and right meters follows CRM.

Headphone monitoring can be switched between following CRM. Headphone monitoring can be switched between following CRM or Self-Op, which switches between From Air and main Mix when the DJ mix is open.

Master section jumpers include a jumper to determine whether the Cue Out is muted when the DJ mic is active, plus pre or post main mix insert mono out and the remote connector for the Director's mic.

The Airmix is an On-Air console worth looking at if you are in for a simple but intelligent mixing console.

Simon Croft, Audio Media