How to Choose a Wireless Lavalier Microphone?
Four Things to Consider When Purchasing a Wireless Lavalier Microphone
1. Frequency
Generally speaking, there are three main frequencies.
UHF (400 MHz and above) has been the standard for many years and generally offers the strongest and best performance. In recent years, the operating frequencies of these microphones have become restricted. This has led to the emergence of newer 2.4 GHz wireless microphones.
These microphones operate in the 2.4 GHz band. Keep in mind that the 2.4 GHz band, similar to your Wi-Fi, is already occupied by a large number of unauthorized consumer products (such as smartphones, computers, and personal media players).
This means they may be subject to interference from these devices, which can cause signal dropouts. They also have a shorter operating range. These wireless microphones are only suitable for use in smaller rooms with clear obstructions between the transmitter and receiver antennas.
Another frequency band frequently used by professional wireless recording microphones is 902-928 MHz. This is a widely accepted alternative for those needing to replace older, outdated 600-700 MHz cordless microphones. Some manufacturers also offer the Very High Frequency (VHF) band between 169 and 216 MHz. With the advent of new digital technology, this may be another viable option.
In addition to the types mentioned above, there are other wireless microphones for mobile video recording. Read the article “Understanding Wireless Microphones for Mobile Video Recording: 2.4 GHz vs. Bluetooth” to learn more about the differences.
- Transmission Range
Different systems have different transmission ranges, ranging from short distances to hundreds of feet. A practical approach to selecting the right product is to consider your distance from the sound recordist and then double that distance to ensure safety.
Furthermore, it’s generally believed that short-range recording wireless microphones don’t transmit well through small obstructions like tables, doors, and soundproof rooms. This is something to consider when considering 2.4 GHz and VHF systems, as they generally don’t have the same range as UHF systems.
- Sound Quality
Digital wireless microphones and analog wireless systems often compete with each other when it comes to recording. There seem to be many reasons to choose the former over the latter, such as battery life (approximately 40% longer) and spectral efficiency (more components can be used within a given frequency range). The biggest improvement, however, is sound quality.
Analog systems compress the audio signal, which covers the entire dynamic range of a vocal or instrument, into a narrow frequency range before outputting it. Digital systems easily accomplish this without companding, resulting in a more natural sound.
Digital wireless microphone systems have become increasingly affordable, making them practically accessible. However, modern analog systems have improved companding efficiency in an effort to narrow the gap in sound quality.
- Latency
Latency refers to the time it takes for a signal to be transmitted as audible sound. It significantly impacts performers. Musicians sometimes complain that they struggle to stay in tune and rhythm on stage because the sound they hear is muffled.
In fact, latency is another key factor in the debate between analog and digital wireless microphone systems. Analog systems offer virtually zero latency because they can directly process high-speed signals. In contrast, digital modules convert the analog signal into digital form before processing it by a microcontroller. Continuous innovations in companding technology have significantly improved sound quality, and advanced engineering now enables high-quality digital wireless microphone systems with latency below 5 milliseconds.
Generally speaking, for conferences and seminars where minimal latency is tolerated, a wireless recording microphone with a latency of up to 15 milliseconds is sufficient. If your production is more artistic, such as a theatrical performance, you’ll want to invest in high-quality wireless microphones with the lowest possible latency.
