07/10/2024
Shared from another group....
I've got some work to do.
Ten Commandments of Wireless
(I) Thou Shalt Have a Wired Backup --- Don’t just have it with you, have it in place and ready to go. In other words, there should be a cable on the floor that you can be plug into your guitar at one end and your amp at the other in mid song if needed. True, the wireless units out there today are far better than in the past, but they can still fail. There is nothing like standing onstage in front of an audience, futilely trying to get sound out of a dead wireless connection.
(2) Thou Shalt Do Thy Frequency Homework --- Know what frequency you are transmitting on and know how to change it if you need to. You never know until you get there what the wireless-spectrum situation is at a venue. There are venues where so much wireless is already being used that plugging yours in requires a presidential decree. If you know what range you can transmit in, it will make your job and the sound guy’s much easier if you encounter interference.
(3) Thou Shalt Not Insist On Using Thine Own Wireless. --- This is a companion concept to the idea that no matter what mic you prefer or carry with you, be prepared to use the standard-issue dynamic that the venue provides. Plugging your ‘‘alien’’ instrument into their ‘‘finely tuned’’ system could cause a problem. This is more an issue with wireless mics and personal monitors than with guitar units, but if you have specified wireless PMs and mics, and the house has a unit of the same model or similar to what you usually use, use theirs.
(4) Thou Shalt Have Diversity. --- Diversity means more than one signal. At first, that meant two receivers with two antennae and a microprocessor that monitored the input to each receiver and then chose the strongest one to send to the output. Building two units into the receiver was not cheap, so diversity was reserved for high-end pro gear. Then, someone figured out that they could accomplish the same thing by using two antennae with the processor picking the strongest signal and sending it on to a single receiver. This led to the terms true diversity (the receiver kind) and just diversity, which usually means antenna diversity. Technology changes quickly, and for a brief period in time this made a real difference, but, as processing power has increased exponentially and antenna technology has advanced, the ubiquitous antenna diversity we see today is at least as good as the true diversity of days gone by. The bottom line is that if you don’t see two antennae, there is no diversity, so consider carefully whether it is a good investment. Note that this does not apply to wireless personal monitor units because they are ‘‘backwards’’ from other performance wireless. That is, the receiver, not the transmitter, is what is in your beltpack. I only know of one diversity PM system on the market right now.
(5 ) Thou Shalt Not Commit the Sin of Parallel Antennae. --- If you have a diversity receiver of any kind, and you set it up with the two antennae on a parallel plane, you are all but negating any advantage of that diversity. Two antennae positioned close together and parallel to each other will—with almost total certainty—pick up the exact same signal. But if you put the two antennae at any kind of angle to each other, you vastly increase the possibility that one will pick up stronger signal than the other. The farther apart the antennae are, the less difference this makes. But, because most MI (musical instrument)–grade wireless receivers are housed in half-rack units, the antennae are no more than eight inches apart, and in this case, eight inches isn’t a lot. . . .
(6) Thou Shalt Understand Companding. -- To properly transmit any musical performance requires a fairly large signal in terms of bandwidth. The problem is that the bandwidth used by performance wireless devices is fairly narrow. ( most performance wireless devices operate in the space between stations in the VHF and UHF television bands—a space that is crowded and getting more so by the day.) To use the least amount of bandwidth, the signal is compressed before it is transmitted and then expanded on the receiver end. This process of compressing and expanding is called companding. Why is this important? Because the better high-end pro wireless units now available do their companding so transparently that only the most golden of ears can really hear it. The downside is that those units are outside the budget of the typical entry-level shopper. Less expensive and older wireless units use companding that you can hear. Generally, a companded signal has less dynamic range than one sent over a standard cable, so many performers have adapted the use of that compressed dynamic range as part of their sound. This is especially true of guitar players, who use that wireless compression to add to the sustain of their solo sounds. (Some digital wireless units just hitting the market that do not require companding including the Line 6 X2 units.)
(7) Thou Shalt Take Care When Mixing Systems. --- A frequency is a frequency, and systems of different ‘‘flavors’’ should work together just fine. In the real world, however, (barring any endorsement deals) you will almost always find that all the wireless in a rack is made by the same company. There is good reason for this. Most companies—especially at the pro end—make software tools that make setting up multiple wireless systems much less of a chore. They also allow the engineer to monitor things such as RF, audio level, and even battery condition from the front of house or monitor position. It can save the show if the engineer can tell you that your battery is dangerously low so you can change it between songs before it dies
(😎 Thou Shalt Practice Proper Transmitter/Receiver Placement. --- To avoid interfering with things such as TV stations, wireless units are very low power. This makes locating the transmitter and receiver in a direct ‘‘line of sight’’ very important. Beware of anything that can block the wireless signal, including your own body. Consider placing the receiver on the floor in front of you, rather than in a rack behind you, if possible.
(9 ) Thou Shalt Not Lose Track of the Mute Button. --- This applies primarily to vocalists who insist on taking their wireless mics out into the audience (by definition, in front of the PA speakers). Unless the system has been thoroughly rung out to allow for such expeditions, this opens the door for big-time feedback. If you need to take the mic out into the audience, know how to mute that mic the second it starts to feed back.
(10 ) Thou Shalt Carry Extra Batteries. --- This goes without saying, but I’m saying it anyway. Have spares where you can readily access them and be able to change them out in the dark. While we’re on the obvious, discard your old batteries ASAP (unless they’re rechargeable), because they have this sneaky manner of finding their way back into your gig bag. D’oh!
