CALREC Putting Sound in the Picture 113LtRt / LoRo downmixesFor each 5.1 main bus, the stereo downmix can be chosen to be LoRo or LtRt.LoRo maximises mono compatibilityat the expense of losing the front rearseparation that a Dolby ProLogic decodercould recover when using an LtRtdownmix.Note that because the number ofmain outputs is halved at highersample rates the number of availableLtRt downmixes is also halved soonly 8 Lt Rt processes will be madeavailable at 96kHz.Bus routingApollo has a very flexible bus structureallowing many routing possibilities:• Channels can route to Groups, Auxs,Tracks and Mains.• Groups can route to other Groups,Tracks, Auxs and Mains.• Mains can route to other Mains.• Tracks cannot route to any other bus.• Auxs cannot route to any other bus.Pre-fader Aux send cut optionsPath sends to Aux output buses can beconfigured to cut under certain conditions,such as the send path’s fader being open/closed and/or the path being cut.These options are set from the>Operate>Bus Config>Auxes page ofthe main application, as shown in Fig 4.The options are set on an output basis,but it is the send from each path feedingthe outputs that are independently cutdepending on the status of each pathrouted to the aux output.For example, if ‘Pre Fader Send cut whenfader closed’ is selected for Aux output 1,the pre-fader sends from each path routedto Aux1 will be muted whilst their fader isclosed.FIG 4 - MAIN APPLICATION, OPERATE>BUS CONFIG>AUXS SETUP SCREENAs soon as the fader is opened, the pathwill send audio to the aux at pre-faderlevel.Pre fader sends whose faders are open,as well as any paths feeding post faderwill still be passing audio to the Aux1output.The options available for muting sends toeach aux output are:• Pre-fader send cut when channelcut (or not ‘on’ if fader have path Onbuttons rather than cuts).• Pre-fader send cut when fader closed.• Pre-fader send cut when fader open.• ‘Bird-Beater’ - Pre-fader send cut whenfader open and not cut. The send isactive only if fader closed, or path cut(or not ‘on’ if on buttons fitted ratherthan cuts).The pre-fader cut when channel cut optioncan be selected in combination with eitherthe cut when fader open or fader closedoptions, however other combinationswould conflict with each other and assuch, selecting one will cancel others.FIG 1 - BUS RESOURCES FOR APOLLO AT 96KHZBus Type Mono Resources Available Max Number Configurable BusesMains & Groups 64 8 Mains, 24 GroupsAuxes 24 24Tracks 48 48
