Digital wireless systems provide high-quality clear audio. This is largely because digital wireless systems do not have a "Compander " ,which is a circuit that reduces noise and maximizes dynamic range for all analog wireless microphone systems. in the analog system, The audio signal is first compressed via the transmitter to adapt to the limited dynamic range of the FM transmission and then expand in the receiver.
The process of compression and expansion, although relatively small in most good analog systems, there are some artificially audible sounds (like Wheezing effect) that 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 compander, and the received signals restore the precise characteristics of the original audio.