Sub-zones with Mid-Level and Advanced Systems

With any of our systems, you can place an unlimited number of speakers into any one zone as long as you add the appropriate amplification to that zone.  As-is, the DMA-1240 and DMA-1275 multi-channel amplifiers, as well as the built-in multi-channel amplifier in the MCA-66, can support 2 pairs (4 each) of 8 ohm speakers across 6 zones for a maxium of 24 speakers.
When using a separate controller and multi-channel amplifier, if you are using less than six zones, then you will have unused amplifier channels available to add into one of the zones, e.g. if you only have 5 zones, you could dedicate four of the channels on the multi-channel amplifier (instead of two) for one zone, and thus have 8 speakers in that zone.  If you are utilizing all six zones, then in order to add more than 4 speakers per zone, you will need to install additional amplification.
A zone can also be made up of several rooms, each with its own independent volume control.  We define a "sub-zone" as an area within a zone that has independent volume control.  A "sub-zone" is forced to listen to the same source selected for that zone, but its volume is controlled using a standard "in-line" volume control- either rotary, or slide-type.  These volume controls are connected "in-line" between the amplifier and the speakers.
When connecting additional amplifiers to the whole-house audio controller, use the fixed level outputs if you do not want the keypad's volume setting to impact the sub-zone's volume, i.e. the keypad in the primary zone has no impact on the sub-zone's volume level.  Use the variable level outputs to have the sub-zone's volume adjusted simultaneously with the main zone.

See Also:How should I wire my home for the Mid-Level system?
 Tips for running Cat-5/6 cable for whole-house audio
 How should I wire my home for the Lync system?
 How do I connect four speakers to a pair of stereo amplifier channels?