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Audix Performance 40 and 60 Series:Analog UHF system, tunable or with 207 pre-coordinated frequencies, switchable transmitter power, single- or dual-channel receivers.
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CAD Audio 3000 Series: Analog UHF system with scanning, switchable transmitter power, and up to 15 simultaneous channels.
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Electro-Voice R300: Analog UHF system with 32 pre-coordinated frequencies and ClearScan scanning.
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Shure ULX-D: Digital UHF system offers several 64-MHz bandwidths, with one- to four-channel receivers, switchable transmitter power, manual/auto channel selection, analog and digital outputs, encryption, network-capable.
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Sennheiser Digital 6000: Digital UHF two-channel system—receiver tunable over 244 MHz and transmitters available in three bands, with analog and digital outputs, encryption, internal multicoupler, network-capable.
Well, the FCC’s 600-MHz Incentive Auction is over, and at least we have certainty on one point. The 84-MHz block of frequencies between 614-698 MHz will no longer be permissible for wireless microphone use once the 39-month grace period, with the clock already ticking, is over. However, there are a variety of details that will still need to be addressed.
What’s changed?
First, within that cleared bandwidth, 70 MHz (in paired blocks of 5 MHz each) will be used by the companies that purchased the spectrum—including T-Mobile, Dish and Comcast. Their use of the spectrum will likely be rolled out market-by-market over the next three-plus years. The remaining 14 MHz, which consists of 2-MHz bottom and top interference guard bands and a clear 10-MHz band smack in the middle between 653-663 MHz, will be available for use by competing white space devices (WSD) and wireless mics.
AKG DMS800: Digital UHF two-channel system tunable over 150 MHz, with wide audio bandwidth, EQ and dbx compressor/limiter, encryption, switchable transmitter power, analog and digital outputs, network-capable.
Second, the television stations that agreed to sell their spectrum will be moved to lower spectrum within the 500-MHz band, either with a dedicated new channel or sharing spectrum with an existing channel. This “repacking” will begin to happen over the next year or two, and will be different for each region. So the remaining bandwidth will become somewhat more crowded, although even the most densely packed market areas should have at least one TV channel of clear spectrum for your wireless mics.
Third, the rollout of mobile broadband and 5G services in the cleared 600-MHz band will happen in phases and with different timing depending on the particular market. If new services begin to be rolled out in your region first, you may have to cease using any existing 600-MHz wireless microphones that interfere with those occupied frequencies earlier than the mandated 39-month grace period.
Audio-Technica 6000-Series High Density Wireless:Specialty system for licensed users offers up to 31 simultaneous channels in 946 – 950 MHz; also 2.4 GHz, digital dual-channel System 10 Pro, with remotable receivers.
And finally, Channel 37, the band reserved for radio astronomy, spans 608-614 MHz, and has never been open for wireless microphone use. So your remaining spectrum for unlicensed wireless microphones and related devices is the UHF spectrum between 470-608 MHz, the VHF band between 169-172 MHz and 174-216 MHz, the 902-928 MHz ISM band, and the 2.4 MHz WiFi band. Wireless microphone use in each of these blocks of spectrum has its own benefits, limitations, and competing devices vying for those frequencies.
The next steps
Perhaps you have existing systems that operate in the 600-MHz band, and will need to transition. Or you have a handful of wireless systems and have a need to replace, upgrade, or add more channels. Given the variety of wireless microphone systems available operating within these frequency bands—priced from entry-level units at perhaps $100 per channel, to reliable workhorse units for several hundred dollars, to touring-quality, networkable systems costing thousands per channel—how do you make your decision? If your long-term requirements for wireless are a headset for the minister and a mic or two for other purposes, and your church is in an area with little potential for interfering signals from television, broadband services, or WSDs, an entry-level wireless system could be all you need. When you are looking at more than a handful of wireless mics, consider a higher quality wireless system that is frequency-agile over at least several television channels and/or self-coordinating, and with detachable antennas and perhaps antenna combining—giving you the flexibility to work around interference and more effectively expand the system.
Galaxy Audio EDX Dual Channel: Analog UHF system with 16 pre-coordinated frequencies and dual-channel receiver.
Note that many wireless manufacturers offer systems at different price and performance levels. You will find reliable systems with very good audio quality, spanning sufficient spectrum, and with enough connectivity to interface effectively with your sound system for several hundred dollars per channel. It’s very useful for your system to have a scanning function that will suggest and/or set itself to the most interference-free frequencies. As you move up the product line, more robust systems with the ability to easily combine and remote antennas, rack-mount, interchange mic heads on handheld transmitters, select specific frequencies, and more are available. Also, keep in mind that first and foremost, the wireless mic is a microphone, and you want to start with a quality audio instrument. If your church regularly broadcasts services, or uses concert-level production values, the features in the top-of-the-line systems may prove valuable—the ability to network and remotely monitor each channel’s performance, Dante and/or AES EBU digital outputs, multiple channels in each 1RU chassis, remotely changing transmitter settings, and so on. Systems at all of these performance and feature levels can be found with both digital and analog technology, though more and more are making the move toward digital transmission.
Lectrosonics Venue 2: Digital-hybrid UHF system with 6-channel modular receiver, tunable over 76 MHz, with internal multicoupler, intelligent iQ filter signal tracking, variety of handheld and bodypack (including mini) transmitters, network-capable.
Digital Wireless
Digital wireless can offer a number of advantages. Digital transmission requires a lower signal-to-noise ratio in order to deliver a usable signal to the receiver, compared with analog wireless. As well, the signal is either on and with undiminished audio quality, or off and silent. “Noising up” and other audio artifacts are rare with these mics. Typically, a lower transmission power is necessary from the digital system’s transmitter compared with an analog unit to cover a similar distance. Many digital transmitters offer selectable lower and higher RF output levels depending on how far the users are from the receivers, and the congestion of the RF environment. Digital systems are more spectrally efficient, so that more channels can be used within a given amount of available spectrum. As a rule, digital wireless systems have a wider audio bandwidth, at both ends of the spectrum, than analog—although some high-end professional analog wireless boasts excellent frequency response.
Samson Concert 99:Analog UHF system with 80 available channels and scanning function.
Keeping Aware
Even with all of the capabilities inherent in newer wireless systems, users must remain aware of the wireless environment, including potential sources of interference such as DTV (digital television), broadband, other wireless equipment already in use, and so on. Learn about which RF bands in your area are currently allocated and which are open, and become aware of which spectrum has been auctioned for wireless broadband or similar uses. In larger installations, it is a good idea to do frequency coordination, and know when you’ve reached the limits of channel density for a given frequency band. A variety of RF scanning hardware and software is available to conduct local environmental scans before setting channels in cleared spectrum—or you may be able to find an expert to conduct the surveys. Complying with cases of interference will continue to be done as it is currently, on a complaint-driven basis.
Sony DWZ: Digital 2.4 GHz system supports up to six simultaneous channels, with wide audio bandwidth, EQ, and feedback reduction DSP.
Licensing
If you are one of the few churches who regularly use 50 or more channels of wireless (includes mics, in-ear monitors, intercom, and similar RF devices) for your services, you should apply for a license. Licensing will give priority to your use of wireless devices during the times of your services and other events, meaning that any interfering, unlicensed users of WSDs or other equipment are required to respect your use of those frequencies. Also, the FCC is opening a special band in the mid-900 MHz band that is only available to licensed users.
The latest offerings
Below are a variety of recent wireless offerings, with the caveat that not all manufacturers release new products each year. Both analog and digital systems (especially at the mid and higher end) are represented, operating in either the lower UHF or 2.4 GHz bands. All are frequency-agile and function across at least a few TV channels. The higher end units have features such as digital outputs and the ability to network and remotely control them, which can be useful for larger, more complex applications. With a proper choice given the requirements of your particular church, these should prove to be good sounding, reliable wireless systems.
