sundance-communications.com/forum Forums General General Telephone & Systems Information Valcom speakers

I'm installing Valcom V-1420 speakers to an existing office. They have speakers on the 1st and 2nd floor. My questions are: can I tap in on the line on the 2nd floor and run a cable up to the 4th floor and add 11 more spekers(approx 350ft)? What quage wire do I need? Do I have to run it from the Page Adapter(approx 500ft)? Is there a limit for how many speakers to how many feet of cable used?

Call Valcom at 1-800-825-2661 and speak with their tech support folks. They are very helpful and will answer all your questions.The following is a cut and paste from their website and they really are the best to answer this.I hope this helps.

Emergency Troubleshooting Assistance for your on-site Field Technicians is available 365 days a year, 24/7. (Your Field Technicians should call from the jobsite equipment room with an equipment list, multi-meter, spare lineman's test set and tone generator.)

We use 24 gauge wire.tip,ring and power pair.You can extend from 2nd flr,but need to perhaps add power supply for extra 11 speakers. Extend tip/ring pr. to all 11 speakers use power pack from 4th flr to extend power to these 11 only.
-John

Renoed is right. There is a sheet on their website that gives you distances and the number of speakers per run for each gauge of wire. The power is the important part, if you don't follow the guidelines you could create problems for yourself. I have been told by my valcom rep that you can loop the audio pair from one source to all the speakers, but not the power. Valcom also makes it easy by assigning everything a power unit. So when you add a power supply it tells you how many units you are adding to the system, when you add a speaker it tells you on the box how many power units to subtract from the system. When you use all power units from one power supply, add another. Hope this helps.

power considerations are you biggest challenge.

if you run 4pr to the upper floors, double or triple up your pair and it should be ok.

I'm sure Valcom would disagree but as far as I'm concerned powered speakers are not worth the trouble for all but small installations and even then why bother. Valcom tried to reinvent the wheel with a paging/background music system product aimed at telephone installers. It uses the wiring and test equipment we are familiar with.

Now we are starting to see this progress into IP enabled powered speakers. Don't know what that is good for unless you need to address each speaker or group of speakers.

Thing is it's not rocket science to install a distributed system using conventional amps and speakers. The advantage too is that there is an almost limitless selection of equipment. The wiring requirements are simple and no power supplies or consideration for powering is required.

-Hal

I agree with Hal, they are fine for small installations, Plus they even states it should be shielded cable to stop interference. What happens when you want to expand. under normal amps and speakers systems you just up grade the amp or put in a second one with audio up link.

Good point about the shielded wire. The audio running around to those Valcom speakers is line level connected to the inputs of those little amplifiers on all of those speakers. So there is gain or amplification after the wiring and any noise will be amplified. Normally the twists of CAT3 wire should keep hum and noise pickup under control but I can see where there easily might be problems that require shielded wire.

Wiring for a constant voltage system isn't susceptible to noise pickup except under unusual circumstances. There is nothing but a passive transformer and voice coil. Matter of fact shielded wire is not recommended.

-Hal

My $0.02.

Powered speaker systems are OK for 5-10 speakers, after that, why bother? I installed 900 of them for Time & Life and when I asked the engineer who "designed" the system why he would do such a thing , it became obvious from his answers (and evasions) that powered systems were all he knew. T&L paid probably at least 10 x what they would have paid for a good constant voltage system.

Shielded cable is for inputs. Unshielded is for outputs. If you have a speaker that's on a "flip-flop" and doubles as a mike, well then it's an input device (at least some of the time) and should be fed with shielded cable. Otherwise, unshielded cable.

I got sent on a repair to a factory/warehouse/office where the newly installed PA system was playing terribly sounding music. Interestingly there was no music source. The contractor had run all the speakers with shielded wire and had not even grounded the shield at the amp.

The shields acted as an antenna and picked up the signal from a local radio station.

(We wound up putting RF chokes on the lines to eliminate the signal.)

Sam