The digital age has been integrated into our personal and professional lives. More and more, we use GPS instead of map books, exchange contact information on mobile phones instead of writing them down, and use Google at home to start research projects instead of library card catalogs. Audio is no exception, none of this will go backwards.
70 years ago, AlecReeves' pulse code modulation patent was born, which helped the invention of the transistor in 1947. This makes the sampling frequency bandwidth of the entire human auditory audio possible. It wasn't until 1970 that audio producers released the first digital recording system.
Among the digital audio equipment that have entered the market in the past 30 years, professional wireless microphones and guitar systems have only recently come out. So, why choose a digital wireless system?
1. Excellent sound quality
The digital wireless system provides high-quality transparent audio. This is largely because digital wireless systems do not have a "compressor", which is a circuit used in all analog wireless microphone systems to reduce noise and maximize dynamic range. The audio signal is first compressed by the transmitter to adapt to the limited dynamic range during FM transmission, and then expanded in the receiver.
Although the compression and expansion process is relatively small in most good analog systems, there will still be some artificial audible sounds (like the gasp effect) that will make the sound of a wireless microphone slightly different from that of a wired microphone. Since the use of digital wireless microphones, the transmission of audio signals no longer requires compression and expansion, and the received signal restores the precise characteristics of the original audio.
2. Compressor (variable)
A digital wireless system can reach the entire audible audio range with a flat frequency response curve.
Digital wireless systems modulate the radio carrier in several steps to convert analog audio into digital signals. The digital audio signal reaches the receiver without being affected by electromagnetic noise. Any RF noise below the critical value will not affect the audio quality. The receiver simply ignores anything that is not 1 or 0. All others are discarded. Only digital signals will be discerned.
3. Longer battery life
Generally, electronic wireless microphone systems have 30%-40% longer battery life than the same analog system. Here is a Shure example: the digital signal transmitter ULX-D can run for 11 hours with two AA alkaline batteries, and for more than 12 hours with Shure SB900 lithium-ion rechargeable batteries.
4. Better spectrum efficiency
By allowing tighter channel spacing, digital wireless wireless systems can simultaneously use more effective compatible frequency points in a certain frequency band. This feature is particularly important in the increasingly crowded UHF television band where many wireless microphones operate. Depending on the manufacturer and model, a digital wireless system can usually deliver twice the frequency that can be used by the same analog system wireless system.
There are more things you need to consider when choosing a digital wireless system:
Compared to analog systems, digital systems may require 10%-20% more budget. Even so: Digital wireless systems can provide features that analog systems cannot provide, including advanced battery technology, extended operating time, more wireless broadcast frequencies, encryption technology, and external interference detection.
Delay is the time it takes for a signal to reach the output port after entering the input port of a digital device. In analog devices, audio signals are transmitted at the speed of light, and the underlying factors are not critical; however, in digital devices, the upcoming analog audio signals need to be converted into digital signals. Then the signal is converted back to an analog signal.
A large number of delay values can cause problems. Most high-quality digital systems produce a delay of less than 5 milliseconds, which is generally acceptable to most listeners.