How to hookup 20 speakers?

[arutzen]

I'm trying to wire a medical office background music system, and I need advice on wiring 20 speakers. Vendors want to sell me a "70-volt paging system," but I don't want to hook up paging, we don't have more than 30 feet to the farthest speaker, and the sound quality is POOR. I'd like good quality, low volume music.

This is what I'm thinking:
Source-satellite radio
2 inexpensive receivers (or amplifiers)
10 speakers per receiver, 5 on each channel
Ceiling speakers-Phoenix Gold 8in 2-way
I don't know the impedance (4 or 8 ohms), but I might put some in series and some in parallel.

Is this reasonable? Aside from using different receivers for different zones, can I control volume of speakers individually?

Thanks for the advice!!!

 

[j_garcia]

You want an impedance matching speaker selector or you will want to use impedance matching volume controls per zone. Even with these, you are going to want decent amps/receivers to drive everything; something that is likely 4 Ohm stable to handle that many speakers at once, and I would use amps rather than receivers.

 

[Rickster71]

Just a suggestion; I wouldn't throw out the thought of a 70-volt so quickly.
Here is a link that speaks to the 'how and why' of a 70-volt speaker system.

http://www.atlassound.com/support/70voltRules.cfm

Systems like it are very common when high numbers of speakers are required. IMHO it would be cheaper than two amps, and two impedance matching speaker selectors, etc.

Also a medical office isn't going to be an audiophile listening area anyway, so it doesn't have to be pristine sound quality.

 

[markw]

Agree. this is what 70 volt systems were made for. It's only monophonic background music anyway. Trying to implement stereo would be a joke for this purpose. Plus, there are some prety nice speakers that do 70 volts nowadays.

 

[Haoleb]

A 70 volt system wouldnt be a bad idea with a setup like this. the only drawback with 70v is the bandwidth of the transformers, And in a medical office I dont think that would really be an issue.

You could also look at the idea of getting 10 or so of those sonic T amps and using splitters to hook them all up.

 

[arutzen]

I really like the idea of using the speaker selector with impedance matching and volume control. If I choose a 6 zone system designed for 12 speakers, I can connect 2 x 4 ohm speakers on each circuit in series for 8 ohms of impedance. That will give me 4 speakers per zone for a total capacity of 24 speakers. I'll use an amp with adequate wattage, and I'll bet it sounds nicer than the horrible 70-volt system I heard. It will also be much more economical!