Yeah, it seemed kind of outrageous to take your initial statement to the effect that "the volume needs to be controlled" and convert it to "we want something that will change the volume in response to conditions changing." You want to lead the elephant. The other suggestion is that they hire someone to follow the elephant with a pooper scooper.


As I pointed out, that 16/2 can be used for a signal to go to the volume control location, which, because of poor design and a desire for a low bottom line, can no longer just be a volume control location.


There's only one thing that makes me think 8 ohms should even be considered, and that is the remote control aspect. I totally advise against it if you're going to consider having one brute amp where the one amp is now! Look at [Link: remotecentral.com] to get an idea of the losses involved. Be sure to actually open the pdf. I think the figures in that post are for an only 25 foot long run!

But it seems others here know of 70 volt stuff that will do what's needed. Learn more about 70 volt.


...So... there's this one installation that has one amp going to eleven zones, and a different installation with 48 zones? Please give us more info, as that fact all by itself makes me think I did not understand the threar up to now.


Yeah, they go in my book!

With 1 run of 16/2 coming from the amp to the 11 VC's it doesn't make this easy.
I am assuming this was sold to the client as a set up that once they adjusted the various volumes, they would leave them and then only have to turn the system on or off. Actually playing around with the volume controls daily was not really part of the initial design. Not that uncommon in a cost effective system, the VC's are merely a way to balance the volume levels in each area.

Only thing I can think of, and this depends greatly on how and why the client wants things to run, is to find something like a controllable speaker switcher.
Take the 16/2 in, split it out to 2 or 4 "selectable" outputs which then are feeding a "group" of the VC's.
This way you will at least be able to turn a group of speakers on or off. Unfortunately, this still doesn't let you play with the volume of each "zone".
TOA SS-9001 does this and has contact closure to allow control of which zones you want to turn on and off.
I guess you could also add a 70v amp that is controllable to run this area of the system and you would then have Volume control of the zones you have turned on, based on the position the VC's were left on.

I would be afraid of doing that... Unshielded wire for an audio signal?

I will try it at the shop...

Last comment.

Use the 16-2 as a pull string for a cat 5 e wire and use baluns to send the audio signal over if it's consumer unbalanced. If it's balanced, yank a 18 2 shield and drain.

Use the cable as a pull string to pull a Cat5, but I'd use the Cat5 for Cobranet and get as many channels of audio you may need to the other end and as a bonus you get Ethernet back to the head end for control. Matter of fact, if you use Cobranet, you can tack on to their existing IP network provided they carve out a dedicated VLAN for you. You could plug the gear into the existing data drops convenient to wherever you need to be.

You would install a Biamp AudiaEXPI-4 to give you four line level balanced inputs located at the head end, into an Ethernet switch, Cobranet over Cat5 to a AudiaFlexCM with 6 PA2 amplifier cards, into two Crown XFMR8 70V transformers, feeding your 11 zones.

Surely you have room for 4RU of gear somewhere at the far end of the conduit using a vertical wall mounted rack like the Middle Atlantic SPM4.

 

I cannot imagine the Cobranet would be considered, as I think it's a pretty expensive addition to the mix. Mike, what amount of money would need to be added to do what you're thinking of?

I'd have much less than zero problem running audio on the 16 gauge wire. I'm telling you to run it as the output of a low-powered 70 volt amp. It's relatively low impedance, which itself immunizes it somewhat from inducted noise.

Cubitus, you single out lack of shielding on an audio cable as a potential problem, but an audio balun does exactly that using CAT5. Shielding is not the necessity we used to think it was. Examine how a twisted cable rejects induced noise to understand this.

The 16-2 is undoubtedly not twisted very much, so I'd be depending on the low source impedance to keep out interference.

The config I described (Frame, six amp cards, transformer rack, cobranet input device) is $6k in equipment with a good margin. The system could do anything that was mentioned in this thread, plus numerous other features that haven't been discussed. I'd sell this system without batting an eye. Add a Crestron processor and touch panel for another $1,500, about $5k-6k in labor, and for $13k all of the problems magically disappear. Far from "cost no object".


That's not what you said. Or maybe not what the OP and myself interpreted your statement as. You said to run unbalanced line level over speaker cable, which is a bad idea.


So you're proposing to fix $100 system by providing a $100 system?


No. Just no.

That's exactly what I meant.


No, you wouldn't, because that implies that this guy who is asking all sorts of strange questions, not listening to answers, and repeating himself, would never buy it.


$13,000 is in the realm of "cost no object" for 99.99% of the people who want this stuff.


No, I didn't, and repeatedly.  I've added bold:



That said "a signal."  It did not say "a line level signal."


That's the comment you responded to.



Giving an example is not saying "do this," and I didn't say line level here either, though it's reasonable to assume that's what would go on twisted pair.


...which would be the low source impedance of a 70 volt amplifier.

Ah hah! The ultimate qualifier. Forget what you want the system to do, forget about make and model numbers, forget about schematic diagrams. It's all about the bucks.

99.99% of MY MARKET, which is corporate, hospitality, higher education, and military wouldn't bat an eye paying $13k for an 11 zone background music system. Especially one that is automated, easy to use, and cheap to maintain. Especially when I can demonstrate that the problems that they've had in the past are a direct result of not spending the extra few thousand dollars for a system that is flexible enough to keep up with changing business requirements.

I can absolutely see a small day spa or a local bar balking at that price, but then again, we don't know what we don't know (about the OP), right?

We may not know what we don't know, but from the OP, we can surmise that the client did not spend a whole lot of money on this.
11 X 70v VC's could have been only a few hundred dollars, add some basic 70v amplifier and some wire and you are not talking about much of an investment here.
To take that and hit him with 13k "to do it right" I bet would get his jaw to drop to the floor pretty quick. Keeping in mind he also has other amps connected to other areas in a similar fashion (at least that's what I think I read in another post)

Most of the folks I know, hearing that $13k would fix such a circumstance, would not drop their jaws. They'd use a variation of a common two word phrase that ends in "you." The variation would be the one that ends in "that."

Mike, your market has learned the value of simple operation. When the daily tasks are simple or nonexistent because the system has been built to do all that is needed, the initial cost is high and everybody is satisfied for years and years.

You got it right. Sorry if that part was not clear enough...

All right, some more details on this job:

I had a 2nd meeting with the owner yesterday. Finally, out of the 11 VCs, he decided that only 5 would need to be automated. The remaining 6 should stay as they are now.

This site has multi buildings, on each side of a boulevard. The music playing everywhere is coming from a web-based interface (Not sure if "web-based" is the right way of telling it, but Ernie please get me back on track if it's not. My English is not good enough in those picky situations...).

In other words, from any ethernet jack, the IT dept can provide me an "MP3 decoder" (this is how they call it) that give me a line-level audio signal from the main stream.

This way, I could "de-centralize" the patch system near the VCs area, and get the audio signal I need.

From there, it's just a matter of reorganize the existing wiring at the VC's, set up a controllable audio matrix, feed (5) 70V amps and get rid of those 5 VCs...

The quote is almost complete, a Vaux audio matrix and RTI XP-6 will be my choice of automation, combined with QSC 70V amps, and I will propose an RTI KX-7 to replace the 5 VCs on the wall so they will still have manual, on-the-fly control.

A nice little solution around $8K. Not so bad...

I will be presenting the quote on Friday morning....

if you use that vaux audio matrix make sure you get a balance to unbalenced audio piece like the ART Cleanbox for each zone.

Since your down to 5 zones just use a DBX Zonepro 1260 to do this. it gives you a very flexible system and some really nice integration with RTI. Plus it takes the unbalanced input sources and outputs balanced audio to the amps. the zone pro is an extremely powerful piece and alot of control for each zone! and drivers are already written for RTI

also to add to it, keep the RTI programing simple and use the timeclock built into the DBX to automatically control the zones volume as your client wishes todo!