Question: How many wireless systems can I use at the same time in the same room?
Answer: As with most things in the audio world, the answer to this is “It depends.” That’s the short (and, perhaps, not very satisfactory) answer. But in order to understand why it depends, we need to review a few issues common to traditional FM (analog) wireless microphone systems. (Digital wireless is a slightly different story, and we’ll address that at the end of this post.)
The first thing to understand is that most wireless microphone systems operate in the same frequency spectrum as broadcast TV channels. For example, the “D band” of our 3000 Series operates in frequencies 655.500 MHz through 680.375 MHz, which is also where TV channels 44 through 49 reside. However, it would be extremely rare to encounter TV stations broadcasting on all of these channels in any given area, so at least some of these frequencies will remain open. And the open ones are free to be used by wireless microphone systems.
To use multiple systems you must also choose frequencies that are compatible with each other. Each of our wireless system models is preconfigured with a certain number of frequency combinations that will “play well together.” For example, if the user is in an area completely free of TV channels, our 3000 Series will provide nine different frequency groups, each with 16 frequencies that are compatible with one another. The user need only stay within one of these groups to use 16 systems simultaneously.
But the user must also be aware of the presence of other wireless systems in the immediate area, as well as that of digital devices such as digital effects units, CD players, A/D converters, computers and so on. These devices are known to interfere with wireless systems.
One last consideration is the location of the recievers. Will they be rack mounted? Will the receivers be placed in a different room than the transmitters? How large is the space you need to cover? Depending on the number and location of the systems, it may be advisable – or even necessary – to use an antenna distribution system and remote antenna.
So, as we come back to our original question (“How many wireless systems can I use at the same time in the same room?”) hopefully you can see that it really does depend on a number of variables. Before purchasing your wireless systems, we highly recommend that you contact the Audio Solutions Team and discuss your needs with us. We have tools to determine what TV channels are operating in your area and will be able to create a custom frequency plan for you. This plan will also help you in placing your systems and determining your antenna distribution needs.
As we mentioned at the start, our new digital wireless products – namely the System 10 line and SpectraPulse® UWB wireless system – offer additional options. These digital systems operate outside the TV spectrum and do not require frequency coordination, making them quite adaptable and easy to use. Again, talking with the Audio Solutions Team is a great way to determine whether traditional FM wireless or one of the digital systems is best for your particular needs.
We hope this post has been informative. Be sure to check back next Wednesday for another “Question of Week”!