Digital Audio Signal Processing, 3rd Edition

Chapter 5Audio Processing Systems

U. Zölzer and D. Ahlers

The techniques, systems, and devices for digital audio processing have substantially changed over the past decades and have now reached a status where software‐based systems have pushed hardware‐based systems almost off of the processing chain. Most of the processing can now be done on general purpose personal computers or tablet computers. All kinds of interfacing of microphones and loudspeakers to the computer world still need dedicated hardware solutions. Lately, microphones and loudspeakers have been improved by digital signal processing and such low‐power devices need specialized hardware such as digital signal processors (DSPs) or field programmable gate arrays (FPGAs). Large‐scale mixing consoles are still benefiting from hardware integration using FPGAs for interfacing and internal multiple signal processing cores. The obvious trend is toward higher integration density and smaller hardware devices integrated into audio networks.

New DSPs with extended interfaces are still used in different application areas where a computer is bulky and excessive. Newer DSPs offer a variety of interfaces to analog‐to‐digital convertors (ADCs)/digital‐to‐analog convertors (DACs), local area networks (LANs), and wireless local area networks (WLANs), which make them very attractive for innovative audio designs with low‐power consumption and low latency. An overview of processing devices is shown in Table 5.1. New software‐based ...