HAI Voice module / siren(s) wiring question

[UNDSioux]

First post.  
 
Just bought an HAI system for a new house.  I have the board, the 2 way voice module, two keypads with mic/speakers and the interior flush mounted speaker/mic.  
 
My electricians ran a 4 wire to where the interior siren is supposed to go.  I understand I only need two wires.  They told me they typically don't do exterior sirens.  Before the insulation, I pulled a 18/2 wire that I was planning to use for an exterior siren.  What was missed is the wire for the interior speaker/mic box.  Pulling it now is going to be a pain in the butt.  
 
The instructions say use 18 AWG twisted pair for the speaker and mic.  Is that necessary?  Can it be non-twisted wire?  I'm leaning toward using the 4 wire conductor that the electricians pulled for the interior sounder for the speaker/mic box and then use the wire I pulled for the exterior siren for an interior siren.  That would eliminate an exterior siren.  If I must use twisted pair for the speaker/mic box, then I will have to pull new wire regardless.  
 
Any thoughts?  Thanks.  

 

[RAL]

For the microphone, shielded twisted pair wiring is recommended.  This will be a big help to keep hum and noise out of the microphone circuit, which is a very low level signal.  You can use wire as small as 24 gauge for this.  60 cycle AC hum tends to be everywhere, and if the microphone wire runs anywhere near an AC circuit, you're likely to pick up noise if you don't use STP.
 
Twisted pair is recommended for the speaker.  Again, the twisted pair will help to reduce noise in the audio, but you may be ok without it.  Shielding isn't necessary for the speaker wiring since it is higher powered than the microphone.
 
You could always try it with what you have in place and if you find it is picking up too much noise, then pull the new wires.

 

[Desert_AIP]

Shielded wire for the mic is a MUST.

 

[Del91574]

TWA needs to be twisted.

I don't know the HAI board intimately, but if the audio output lands on the same board, you don't want to induce noise into the circuits wherever possible.

 

[UNDSioux]

Thanks.

Anybody know where to buy 16 gauge or 18 gauge twisted pair wire that is shielded for the speaker without having to buy 500 feet?

 

[RAL]

I don't think you need shielded wire for the speaker, unshielded twisted pair will be fine.   You do need shielded twisted pair for the microphone.
 
I often find odd lengths of wire on eBay.  Otherwise, buy 500 feet and resell what you don't need on eBay.

 

[pete_c]

Here many years ago ran shielded microphone cable to take line level stuff from the basement to the attic.  It works OK today for line level audio.
 
I do see a spool of 500 feet Belden #8413 cable on Ebay right now.  That is only one pair of shielded 24 guage wires.
 
That said I have tried those audio line level baluns that utilize standard catXX cables in a commercial environment. (~100 feet run)
 
The audio baluns did work for me just fine.
 

 
For zoned audio speakers I ran 2/4 16 gauge PVC jacketed cable and Cat5e for zone controllers.
 

 
Found an interesting couple of articles:

 

What’s the difference between Mic, Instrument, Line, and Speaker level signals?

In the audio world, there are 4 signal levels that we deal with: mic, instrument, line and speaker.

1 - Mic level is the lowest, or weakest, level signal of the four and requires a preamplifier to bring it up to Line level.

2 - Instrument level signals live between mic and line level signals and have the most variation. You typically see this kind of signal come from an electric guitar or bass. They also require a preamplifier to come up to line level.

3 - Line level signals are the highest level signals before amplification. This is the type of signal that typically flows through your recording system after the preamplifier stage and before the amplifier that powers your speakers. There are two types: Consumer and Professional. Consumer line level is rated around -10dBV and is what you’ll find in products like a CD player. Professional line level is rated around +4 dBu and is found in things like mixing desks and signal processing equipment. If you see that little switch on your gear that says +4 or -10, that’s what that’s for. Be careful not to send a line level signal to a preamplifier expecting a mic or instrument level signal.

4 - Speaker level signals are post amplification. After a line level signal enters an amplifier, speaker level signals are output to your speakers. These signals are much higher in voltage than line level and require speaker cables for safe signal transfer. You should never plug a speaker level signal into a source expecting anything less than a speaker level signal.

 
http://www.sweetwater.com/sweetcare/articles/whats-the-difference-between-mic-instrument-line-and-speaker-level-signals/
 

Building a new home, and planning to wire for  multi-room audio, including outdoor speakers.  Want to source from single receiver, with volume control on outdoor speakers and 3rd room.  Questions I have;

1 - Can I reliably use Cat5e wiring for my in-ceiling speakers, if so will 4 runs per speaker be sufficient?  (32 total 24AWG wires)
2 - Secondly, do I need to braid the main CAT5e runs and/or strip the shielding to expose and further braid the individual 24AWG wires?  I've seen other forums listing both ways, and I've also seen forums saying you don't need to braid at all.

 

I can't for the life of me figure out why anyone would want to do this.Even if you've got a boatload of cat 5e sitting around.

Despite the claims of some "aficionados" (whose technical reach exceeds their grasp) there is absolutely nothing to be gained by using data cable as speaker cable. Not even the most esoteric high-end application, much less in multi-room applications where the signal will be passing through passive attenuators.

Save yourself a lot of time, money and aggravation. Use speaker cable that is sized for the length of your runs and rated for in-wall use.

If you do proceed with this plan you should know that stripping the jacket off of the cable voids any in-wall, riser, or plenum rating the cable may have had. In other words, it won't pass an electrical code inspection.

 
http://community.crutchfield.com/home_theater_and_audio/f/11/home-a-v-components-speakers/t/23332/new-home-construction-speaker-wire-cat5e
 

 

[ano]

For mic audio, I second what Pete_C suggested. Even with shielded cable, you are very likely to pick up noise, especially if the distance isn't very short. Use audio baluns to convert to a "balanced audio signal" then use twisted pair wires for the leads. You might need three conductors (with the ground NOT twisted), or some use only two conductors. It doesn't hurt to shield that also, but its typically not required. (The shield can be the third ground conductor.) On the other end use the same transformer in reverse. 
 
Search for "balanced vs. unbalanced audio" and you'll find plenty. It costs a bit more for the transformers, but it should be worth it if you don't want noise.