The term "DAW" simply refers to a general combination of audio multitrack software and high-quality audio hardware — the latter being a specialized audio converter unit which performs some variety of analog-to-digital (ADC) and/or digital-to-analog (DAC) signal conversion. For example, a workstation could have eight discrete audio inputs, and two or more audio outputs for playback monitoring or routing signal to other devices. Systems can have as few as two mono inputs and outputs — the discrete audio inputs and outputs provide for simultaneous multitracking dual mono sources or stereo recording. A professional DAC performs the same function as a common sound card, but is generally of higher quality and offers sonic or functional advantages when compared with its consumer cousin.
While almost any home computer with multitrack and editing software can function somewhat as a DAW, the term generally refers to computer systems which have high-quality external ADC-DAC hardware, and some form of audio software; some of which is commercial proprietary software such as Cubase, Nuendo, Logic Pro, Pro Tools, Adobe Audition, SADiE 5, Sony Sound Forge, Samplitude, Soundscape, SONAR, ACID Pro, FL Studio (formerly Fruityloops), Ableton Live, Tracktion or Digital Performer, some of which is free software such as Audacity and Ardour. Besides having high-end sound cards most DAWs also require a large amount of RAM, fast CPU(s) and sufficient free hard drive space.
DAWs generally come in two varieties:
Audio on the system was stored on disk pack drives, with the audio transferred onto the drives from Soundstream's proprietary digital audio tape recorders using a Unibus tape-to-disk interface also of the company's own design. Soundstream also developed a digital-to-analog interface for this system for interfacing to conventional analog tape recorders as well.
In 1981, recording engineer Roger Nichols built a digital audio workstation of his own design, using a S-100 bus-based computer with a Micropolis 8" form factor 32 MB hard disk used for storage of digital audio data. It interfaced digitally to a 3M multi-track digital audio tape recorder in his studio, and was used to edit audio from the recorder. Nichols' system was used during the recording and production of Donald Fagen's 1982 album, The Nightfly.
At the late 1980s, consumer level computers such as the Apple Macintosh or the Commodore Amiga started to have enough power to handle the task of digital audio editing. Macromedia's Soundedit was the first audio editing software to appear for the Macintosh in 1986, but the concept was made popular by a company called Digidesign, who in 1987 introduced one of the first hardware & software packages for the Apple personal computer for editing audio. The software was originally called Sound Tools and it was later renamed to Pro Tools I. This was the predecessor to the now-industry standard Pro Tools system. Many major recording studios finally "went digital" because Digidesign had modelled its Pro Tools software after the traditional method and signal flow present in almost all analog recording devices. At this time most of the DAWs were Apple Mac based (Pro Tools, Studer Dyaxis, Sonic Solutions Around 1992, the first Windows based DAWs started to emerge from companies such as Soundscape Digital Technology later acquired by Mackie then by SSL, SADiE and Spectral Synthesis. All the systems at this point utilised dedicated hardware for their audio processing.
In 1994 a company called OSC along with Digidesign technicians launched a 4 track editing-recorder software called DECK II, (only $399,95), employed in The Residents' "Freakshow" LP. The first Windows based software-only product was Software Audio Workshop (SAW) from IQS and it was able to record, edit and mix 4 tracks of audio. It became heavily used throughout US radio stations.
Multitrack DAWs support operations on multiple tracks at once. Like a mixing console, each track typically has controls that allow the user to adjust the overall volume and stereo balance (pan) of the sound on each track. In a traditional recording studio additional processing is physically plugged in to the audio signal path, a DAW, however, uses software plugins to process the sound on a track.
While DAWs are capable of mimicking the functions of a traditional recording studio, there are areas where they excel, and in some cases they can do things that are impossible without a DAW.
Perhaps the most significant feature available on a DAW that is not available in analogue recording (some other forms of digital recording do have this) is the ability to 'undo' a previous action, which makes it much easier to avoid accidentally erasing or recording over a previous recording.
Commonly DAWs feature some form of automation, commonly performed through "envelope points." Each dot represents one envelope point. By creating and adjusting multiple points along a waveform or control events, the user can specify parameters of the output over time (e.g., volume or pan).
Consolidation and compatibility within commercial spaces, along with the early adaptation by many major recording studios has bolstered the user base and reputation of Digidesign's Pro Tools for recording and editing audio. Also Apple Computer's Logic Pro, MOTU's Digital Performer, Steinberg's Cubase, Cakewalk Sonar, FL Studio, and Ableton Live are all common choices for music production.
Detailed information of commercially available programs are available in other articles.
Other professional DAWs that use a combination of hardware and software include;
There are many free and open-source programs that can facilitate a DAW. These are often designed to run on a variety of operating systems and are usually developed non-commercially. The LADSPA plugin architecture, the JACK API and the ALSA soundcard driver represent the 'cutting-edge' in free and open source DAW development for professional audio production.
The development of digital audio for Linux and BSD fostered technologies such as ALSA, which drives audio hardware, and JACK or aRts (analog Real-time synthesizer). JACK allows any JACK-aware audio software to connect to any other audio software running on the system, such as connecting an ALSA or OSS driven soundcard to a mixing and editing front-end, like Audacity or Rosegarden. In this way, JACK acts as a virtual audio patch bay, and it can be configured to use a computer's resources in real time, with dedicated memory, and with various options that minimize the DAW's latency. This kind of abstraction and configuration allows DJs to use multiple programs for editing and synthesizing audio streams, or multitasking and duplexing, without the need for analogue conversion, or asynchronous saving and reloading files, and ensures a high level of audio fidelity. Linux and BSD also support the aRts platform, distributed with the K desktop environment, KDE. The aRts system is a modular software synthesizer and soundserver that handles system sounds, recording, playback, and other audio tasks within KDE. aRts modules may be assembled in custom configurations using aRts Builder and used in audio production. A comparable proprietary product is ReWire.
There are several non-commercial and open-source front-end programs that can facilitate a DAW. Audacity is a free and open-source digital audio editor that can run on Mac OS X, Microsoft Windows, and Linux; it is particularly popular in the podcast community, and also has a large following among the visually-impaired due to its keyboard interface. Rosegarden is a multi-featured audio application designed for KDE that includes audio mixing plugins, a notation editor, and MIDI matrix editor. The MusE Sequencer is a similarly featured audio application that includes an audio mixer, MIDI sequencer, and soundserver that has been developed for Linux systems not running the K Desktop Environment. Other open-source programs include virtual synthesizers and MIDI controllers, such as those provided by FluidSynth and TiMidity. Both can load Soundfonts to expand the voices and instruments available for synthesis and expand the ports and channels available to synthesizers. Such virtualization allows users to expand the traditional limitations of ADC-DAC hardware.
The Linux Audio Development mailing list, LAD, is a major driving force in developing standards, such as the LADSPA plugin architecture, for free and open systems. The VST plugin standard is supported as an option by some such programs but is generally implemented as a separate plugin, not a built-in option, due to Steinberg's licensing scheme. Among others, the creators of Audacity provide an optional, somewhat minimalist, VST-to-LADSPA bridge plugin for their software, but it is a separate download.