On September 8, 2019 at 11:21, Brad Humphrey said...
70V or 100V (25V is also an options with some systems) makes no difference on sound quality. The different voltages allow for different configurations of a system. Which by the way; at 100V the tap settings on those speakers is 15w not 7.5w anymore. So you can NOT run 9 of those speakers at 100V setup, without eventually burning that amp up. You have to use the 70V configuration, so the minimum tap is 7.5 watt.
For the moment, ignore the man behind the curtain and just assume some wizard is running things.
You know what wiring changes you have to make to convert a 70 volt system to a 100 volt system? NONE. Sorry, but I feel that at this point in your education it's not worth trying to explain. A reason that there's a single output point labeled "70/100 Volt" is that the wiring is the same but the concept varies slightly from one to the other. Just be sure you're ALWAYS looking at the 70 volt numbers when you're wiring a 70 volt system. Ignore the 100 volt numbers.
Regular stranded speaker wire is all you need, with the appropriate UL listing. Meaning use plenum rated for plenum spaces, riser rated for between floors, etc.
Do NOT use solid wire. Why would you do that? It would work but you are causing yourself and anyone else that has to work on it grief.
I see zero grief caused by using solid wire. What about solid wire would cause anyone grief?
You could use shielded wire if you want to but there really is no need. 99.9% of the time, shielding isn't going to do anything for you on speaker wiring. That last .1% is because there is always some weird installation waiting out there - neon tubes laying parallel to speaker wire or something.
Something not mentioned anywhere is this thread so far - 70V volume controls!
This is a restaurant. Inevitably you are going to need to have the ability to adjust volume in different areas of the restaurant. Even shut volume off completely in a section. Installing some 70V volume controls is a simple & cheap way to accomplish this on a simple system like this.
Simple, yes, cheap, not necessarily. A properly done 70 volt system can be a daisy chain of wires out from the amp. If you then decide you want to lower the volume of a certain set of speakers, you have to modify the original wiring, which might require adding one or more home runs from a distance from the amp. It all depends on where you want to add the controls. It is BY FAR best to think through whether you'll need to trim the volume of any speaker(s) and run separate home runs for each such group of speakers.
Just need a volume control for each area. So if there are 5 speakers up front in the main area and 4 speakers in a back area, you might only need to get 2 volume controls. If you have 4 divided areas, then 4 volume controls.
This is totally correct.
Wiring will become a little more complicated if you are not familiar. You need to either home run from each volume control location, or wire your loop thru each volume control location. A separate loop wires out from each volume control location to the speakers.
I like home running as much as possible. It uses more wire and more time to install but is easier to troubleshoot and make changes in the future.
Absolutely true.
Never state that you're wiring speakers in phase because you're ALWAYS wiring speakers in phase (unless you make a wiring error). There is zero reason to wire any speakers out of phase with the others, so you're just bringing up subjects worthy of no discussion at all. Saying you're wiring speakers in phase is like pointing out that you're going to hold your breath when you swim under water: of course you are, everybody does, and you'll get in trouble if you don't. The only difference is that wiring speakers out of phase won't be fatal, while breathing under water will be.
