A common request for many audio systems is the delivery of background music or some other audio source to all (or many) zones. Following are a few examples:
- A large department store requires that the same background music play in all areas on all floors.
- A large conference center requires a variety of background music sources be made available to all of its zones.
- A multi-room sports bar/restaurant requires end user control in each area for choosing between background music and TV audio for that area.
Have you ever designed and implemented a requirement resembling these descriptions? If so, then you know how quickly these situations can become a nightmare of matrices and wiring—especially if the requirement is for multiple input channels to all zones. You wire it once, and then you wire it again and again.
The HAL System designers examined the common characteristics of this often cumbersome and difficult configuration and came up with a solution that is so simple, you'll quickly forget that mess of matrices! The solution? It is a special processing block called the Distributed Program Bus.
When a system requires that one or more of its audio sources be made available in all zones, you simply wire those audio sources as inputs to your Distributed Program Bus. Then, when you add Zone Processor blocks to your system, each block automatically provides a connection to the Distributed Program Bus. All of the routing is handled internally by the Distributed Program Bus. Simple as that! No kidding! You configure and wire the input sources common to all zones only once and they magically become available to every zone you create!
note: To incorporate the Distributed Program Bus into a zone in your system, you must use Zone Processor blocks (or Room Processors if you are configuring a Room Combine situation) to define those output zones. The Distributed Program Bus is not intended to be manually wired to other blocks in your system, thus it has no output node. Instead, the Zone Processor block (and Room Processor blocks—used in a room combine system) provide an automatic behind-the-scenes connection to the Distributed Program Bus.
The following image illustrates the relationship between the Distributed Program Bus and Zone Processor block: