# Com systems

#### u_dakka

##### Member
im an absolute newboy to this whole world but i have dreams - some of them about the theatre! Our school is currently doing a production of 'On the Razzle' which isnt that complex i know but it would be really cool to have a com system we did Les Mis last year but we borrowed coms for that. we have about 6 PMR446 walkie talkies already but i just want to know your guys opinions on:
1) whether we should stick to walkie talkies
2) costs of XLR com systems (btw im in the UK so please try to avoid $) 3) whether we could build our own 4) whether its worth going wireless your thoughts are much appreciated techies rule!! #### Nephilim ##### Active Member I would suggest to moving to professional communications gear ASAP. The biggest problem with standard two-way radios is that they are half-duplex - only one person can talk at a time. Professional intercom systems, whether wired or not, are full-duplex, and when your deck is chatting about the hot guy in B2 and you need to deliver a cue, full duplex is very necessary. I would have no clue what the cost of complete installation of a wired intercom system would be, especially not in pounds. Perhaps someone European or with a better feel for pricing can help with that one. There's another thread around here on building your own intercom, it's possible, it's a matter of how far you want to go with it. For retro-fitting, wireless is awesome - no cable to run or holes to drill, etc. However, it is more expensive than wired intercom gear. #### u_dakka ##### Member soz im being very short sighted - i cant actually see where it is that the other topic is on building your own. our school has got itself all wired up with XLR points all round the hall would that mean that itd be better to be go XLR. anyone know of a website that would help in the actual building and wiring of the coms? #### cruiser ##### Active Member The mic points around your all could quite possibly be inputs, so you can use microphones in any part of the hall. These points would not be suitable to run cans off, as you need to send the singnal back down the line. On shows I have done, where I need to get the comms down to the backstage area, is generally to put the main comm box with the sound desk and use one of the returns on the multicore to send it down to backstage, then i can generally loop a few comms of the one backstage, and also loop off the main box too lighting, sound and spot. #### The_Terg ##### Active Member Assuming that a wireless is too much money, you would need a 4 or 5 pin cable to run headset audio preferably. It seems like if you are REALLY strapped for cash, the best bet would be a 'live phone' setup like as is displayed here: http://groups.google.com/groups?hl=...6&[email protected]&rnum=1 If you have a little bit more money, then you would want something like this: http://207.212.7.216/portacom.lasso All of this was taken from the other com system thread here: http://www.controlbooth.com/postt525.html Which you could read to get a little bit more info from. #### BenFranske ##### Member You don't need a 4 or 5 pin cable if you're using a ClearCom type system, these use standard XLR mic lines to communicate so you can run them over the wiring already in place... #### soundman ##### Well-Known Member Figure this for wiring one point SL, SR, FOH 2 in the booth but thats where the box should be so no prob then one by each spot. If you have clear com you can daisy chain packs so one point could hook up multiple people but im not sure about others. Also not everyone on the deck needs coms even though they might want to hear chances are they dont need to. All that really need coms are the stage manager, spots, fly, FOH, and the orchistra to start he show. Also any speaicel things like pyro or video need them too. #### miniwyo ##### Member Clear Com is great for stationary places but if you have a clear com system it would probably get some compatible wireless headsets. RJ Rock Springs Wy #### ship ##### Senior Team Emeritus Premium Member Were I running Clear Com in a perminant install, actually doing a 5 pin DMX run of it might be useful if not a double run of it to individual jacks. Two channel Clear Com uses the 6-pin Switchcraft Standard arrangement of plug, but does not use the center pin or if it does, it's not using pin 5. Don't remember anymore which one is not used. In any case a two pair shielded DMX run to the clear com station would work well for this dual channel system in having one channel for the follow spots, and another for the rest of the crew. A second run of it would be useful should there be a problem in one cable you can go to the second run of it. To some extent you might even be able to send both cables to the same outlet as long as you used a multi-pole switch to switch between the two main and backup runs. Than you only need one outlet and the switching would only be necessary to be done where the base station plugs into the house system. Definately go with the 6-pin outlets however, this way there is no chance of plugging a mic or DMX line into your com system unless you are using ETC Link gear. This is given a two channel system. Even if you cannot afford such a system at this point, if doing wiring you might as well wire the place up for it so when and if you do upgrade to dual channel you won't either be locked into one channel in some places, or have to re-run the com system. Adaptors are easy to make between a single and dual channel system. While running cable you might also want to run a line or two of 3-pin digital, 5-pin DMX and what the heck, Cat-5 cable in one to two lines of it also. Might not need any of the flexibility yet but once you do the work is done. Especially since Cat 5 is cheap and can be used for DMX signals, I would at least pull a run or two of it at the same time as the Com system. #### RonaldBeal ##### Well-Known Member #### emanueltech ##### Member in our theatre we have an old system there are many XLR jack ins around the backstage area some at the front and two in the box THESE ARE NOT MIC INS as there is a seperate Stage Box for that , and i found loads of xlr headsets but i cant get the buggars to work Tom Clements Technical Director E.S.S.D +00447946582074 #### ship ##### Senior Team Emeritus Premium Member Given headset, belt pack and base station, I would tend to check the wiring both at the XLR connector and inside the headset for broken wires. Very often someone will move away from the wall of drop their headset which in addition to destroying mic elements and ear speakers will pull the cheap cord to the headset's wires out from their terminals. If you find a lot of problems with this, given most headsets use a four wire, switching it to a 22ga two pair DMX cable with the shield soldered to the frame lug of the terminal should offer greater strength against pulling the wires out of either terminal. This given the new wire will fit within the headset's strain relief. Anyway, back in the days before I found someone else to repair such things, non-working headsets were most commonly a wire or some that pulled out of a terminal. #### ee61re ##### Member try these: http://www.rcrowley.com/comclone/ A knowledgable friend of mine has taken that design, and made a few minor alterations, we are putting together a component shopping list at the moment. We think the price per beltpack will be less than £50. Headsets will be the expensive bit, although you can just use a 'normal' computer type headset - it depends on what kind of environment you use them in. Computer headsets would be fine for our purposes in the control room, but something a little more hardwearing would be better for people on stage. Rob #### zac850 ##### Well-Known Member OK, I just built a wired intercom system for my school (well, bought the pieces, waiting for them to be delivered). There are 4 things you need. They are: 1) A power supply. Clearly, the system needs power, you get a power supply. 2) Boxes. These are boxes that clip on your waist. They have 2 buttons usually, a PTT (push to talk) and a call button. The PTT button makes it so that your microphone is live and you can talk. The call button lights up a light on everyone else's belt back, and (maybe) they will put on their headset when they see it and you can talk to them. 3) headsets. There are many styles of these. They go on your head and have either 1 or 2 earphones and a boom microphone. you listen and talk. This plugs into the box on your hip. One headset per beltpack, one belt pack per person. The headset and the belt packs can be switched around, but one is useless without the other 4) XLR cable. Any modern wired system that you would buy off the shelf runs on 3 pin XLR cable. Make sure to have enough to pass around for everyone. Notes: I thought about going to a wireless system. While working as run crew in my local theater, I have often wished for a wireless clear-com system. However, it is not worth$6,000 to me to get 6 wireless clear-com belt-packs. So I went with a wired system.

Clear-Com is the big brand, but its sort of like calling a tissue Kleenex (or an elliptical spot light a Leko). There are really 3 companies that make this type of system. Clear-com is the big one, most expensive, and the most durable and best. Telex is the middle range, cheeper prices, but less quality. Production Intercom is the third. It is cheep. I ordered my schools system from them, but have not received it yet to tell you how well it works. However, I spent a tad under \$1,500 and got a system of 6 stations (1 power supply, 6 belt packs and 6 headsets). I already have enough XLR to use, so I didn't order that.

Some power supplies come with a station in them. These are usually the SM's. Also, some systems are 2 channel, so you could put your spot lights on channel A, and your run crew on B, so one can talk without being bothered/bothering the other. The SM's console was the only one that was able to switch between the two systems, and had the option to broadcast on both at the same time. I did this last year because I had a talkative FSO, and I didn't want him bothering the rest of my crew.

I think that is enough info to set up a system, at least I hope so. I told my school to purchase from
http://northernsound.net/Sales/salesframe.html
On the left is Production Intercom, click that and look at the prices of everything.

Good luck! I hope it is within your price range.

Oh, and walkie-talkies suck. i tried to run a show off them, and it was hell. Coming from a house that had a lovely clear-com system, it was horrible. It was worth the investment. As one of my friends said when we were trying to convince the board to approve the money "its like a company trying to run its self without telephone or fax service". It is worth the investment.

#### ricc0luke

##### Active Member
Going back to the second post-

Nephilim:
Two-way radios simplex, not half-duplex. Half-duplex is a new system designed by Production Intercom. For more info, goto my posting about it in the news forum, or goto www.beltpack.com

It is my personal experience that Production Intercom has a better system than Clear-Com, but if you want full-duplex wireless headsets, Telex has the best. Keep in mind that most of these components can be mixed and matched to create the best system possible.