“My band travels around the region a lot and several members use wireless equipment (guitar, mic, or both) and it seems like almost everywhere we go at least one of the systems doesn’t work due to interference. So we’ve decided to upgrade to frequency agile systems, however, I hear conflicting reports on whether I should go with UHF or VHF units. Please advise.”
The ability to vary the operating frequency of your wireless units should dramatically increase the overall reliability of them as you travel. Whether you use UHF or VHF is of less importance, unless you use many wireless systems on stage, and by ‘many’ I mean more than 10 or 15.
Many people mistakenly think that UHF is an inherently better technology. It is not. The difference between UHF and VHF transmissions is only the frequency range or ‘band’ they are in. The technology, or principle of operation is the same. UHF frequencies are higher so the componentry used in those devices must adhere to very tight tolerances, and therefore tends to be more expensive, which helps perpetuate the myth that the technology is better.
The main advantage of UHF operation is that there is less chance of interference. One of the more common problems with wireless operation is interference between wireless systems. Since there are considerably fewer UHF wireless systems in use at present, the chances of this type of interference are reduced. However, this problem can generally be avoided in VHF systems by properly selecting operating frequencies.
If you’re show utilizes many systems it can be easier to find good frequencies for all of them to operate if they are in the UHF band. And though there is no difference in technology, interference due to spurious outputs from other radio frequency equipment is somewhat less of a problem at UHF frequencies because there are fewer transmitters operating at frequencies likely to cause problems. Interference due to electrical equipment, digital devices, computers and other electronic equipment is also generally lower at UHF frequencies. This is because noise from these sources becomes less intense as the frequency increases. Interference of all types does not travel over as great a distance as at VHF frequencies. So there are some ‘advantages,’ but they come at a cost, and depending upon your situation may not be significant.
VHF systems cost less and have a wider variety of choices and options. They also do work better than UHF systems in ‘some’ circumstances. For example, because VHF frequencies are lower they can sometimes work better when the transmitter and receiving antenna are not in sight of each other. Most UHF systems are in fact considered ‘line of sight’ systems, but they can have more range than comparable VHF systems.
Your Sweetwater Sales Engineer will be happy to weigh these and other pros and cons against your budget with you.