Due to the fact that most signals are already recorded or automatically generated into a digital representation and stored in a machine-readable way, the use of hardware devices for speech analysis and measurement has more and more receded into the background. The most wide-spread tools are
The use of hardware devices is in many cases motivated by mobile use of long-period and on-line sound measurements.
A wide selection of software tools is available in the field of signal processing, some of which are specially equipped with functions for speech processing. Included among these functions are algorithms for spectral analysis , formant analysis, F0 determination, speech coding and digital filtering up to complete packages for speech synthesis or speech recognition . The functionality, efficiency and cost of these tools differ widely, depending on the family of applied computers and operation systems. Many tools are general purpose, and constitute a complete speech processing toolkit. Most of the more elaborate systems include acoustic playback , graphical data representation, data import and export functions, history tracking, and programming interfaces with ready-to-use function libraries.
Some software packages need the support of special hardware like digital signal processors , but there exist also cheap and easy-to-use programs running on standard Windows-PCs (like ``CoolEdit'', a shareware tool that can be obtained via the Internet). Speech processing packages include ESPS/waves+, matlab, SLM and RESAM .