Monday, February 23, 2009

Distributed Audio options

Rob Schultz, President of Inspired Electronics, Inc., was recently published in Electronic House magazine's Ask a Pro section. Read the original article here: http://www.electronichouse.com/article/q_how_much_power_do_i_need_for_multiroom_audio or continue reading.

Q. I just moved into a house that is pre-wired for speakers & volume controls in 3 rooms, 2 outdoor porches, a media room and a family room. I will be buying a new receiver and amplifier but don’t know how much power I need or what Ohm speakers/controls I should get. Any budget conscious recommendations or guidance for a 1st time do-it-yourselfer? - John, Dallas TX


Rob Schultz, of Inspired Electronics, Inc. offers up this solution:


The most basic approach is to have a speaker selector and volume control unit at the head end, and split the output from the receiver. This is simple to install, and pretty inexpensive if the house is already wired. The speaker selector must be impedence matching, which means there’s a switch that lets you tell it how many speaker pairs there are. When you select the right number of speakers, the unit adjusts for the impedence of the speakers so you don’t blow the amplifier. The main drawback of this sytem is that you can only control what’s playing and the volume in the main room. So when your favorite song comes on, you have to run to the main room to turn it up!


You can also use a speaker selector in the main room with individual volume controls in each room. Hopefully the pre-wire has service loops to the right volume control locations, and you know where those are! Use impedence matching volume controls in this scenario. Now you can adjust volume in each room, but you still have to go back to the main room to change what’s playing.


For either option, we plan a minimum of 20 watts per zone, and 40 watts for outdoor zones or large rooms, and we spec 8 Ohm speakers. For more zones or when more volume is desired, we use either a high-power stereo receiver with a speaker selector, or a low-power receiver with a distribution amplifier, such as the Niles 1230 (12 x 30 watts) or Niles 1260 (12 x 60 watts).
By splitting your audio signal, you decrease power and volume by as many ways as you have zones. So if you have a 50 watt amplifier split 5 ways, you get only 10 watts per zone - not even enough for background music.


More advanced options allow you to control the equipment from each room, provide metadata feedback on the keypads, and play different sources in different rooms.

If you're interested in having audio throughout your home or business, visit our web site at http://www.inspired-electronics.com, or call Keith at (847) 471-4420.

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