In several months of spotlighting the problem-solving corps in Shure's Applications Engineering Group, we have finally identified one of the very few who isn't an after-hours sound engineer or bassman.

In fact, Doug Totel's passions run more to HAM radio. A background in broadcast engineering and telecommunications put him in a very good place four years ago when he joined Shure. He can probably answer just about any audio question you might lob his way, but his real area of expertise encompasses wireless, telecom (for instance, Shure's conferencing systems) and networking issues.

"Interacting with people from all over the country to solve technical issues offers the opportunity to share information and ideas as well as learn lots of new things. It is a rare day that something new is not learned, and the folks who call us with questions keep us on our toes to find the answers to their questions."



We asked Doug to talk about one of his favorite topics – wireless systems.

A frequently asked question is how many wireless microphone transmitters can be linked to or supported by one receiver.

Potential users often want to simplify the wireless systems, and using a single receiver could save money as well as simplify the audio connection to their mixer/amplifier sound system.

But alas, each wireless microphone system used simultaneously must operate on its own unique frequency to avoid serious interference. Consequently, there must be a dedicated receiver tuned to the specific frequency of each wireless microphone. Each wireless microphone is then connected to an input on an audio mixer, which provides the individual volume control for each microphone.

There are some products that feature multiple receivers in a single chassis, (such as the Shure UHF-R® series which has an available dual receiver). But in the end, there is a still a specific frequency and a dedicated receiver for each wireless microphone channel.

We assist customers on a daily basis with frequency coordination for all combinations of wireless microphone and personal monitor systems. Especially for larger wireless installations, careful frequency selection is important for high quality audio and interference-free transmission.

When selecting frequencies, there are three primary criteria to consider:

1) choose a frequency that is not coincident with a local TV broadcast station

2) observe the recommended minimum spacing between channels, and

3) select frequencies that are compatible with each other to avoid intermodulation interference.

What's intermodulation? That's where signals from multiple wireless microphones can mix and create interference to other operational wireless microphones. For a detailed discussion of wireless microphone frequency selection, Shure Notes readers can download our "Selection and Operation of Wireless Microphone Systems" educational guide, available for free.

We often recommend that customers consider using the Shure "Wireless Workbench®" (WWB) software, also available for download free from the Shure website. The WWB software features a frequency compatibility module that is easy to use and can quickly calculate compatible frequencies. When setting up new wireless microphone systems or re-coordinating existing systems, Wireless Workbench can be a real time saver.

Have a question?
Need to connect with the Shure Applications Engineering Group?
Call them at 847 600 8440, e-mail or visit the FAQ section of the Shure website.