Digital audio workstation

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Originated in the early 1980s, the term digital audio workstation (DAW) originally referred to a tape-less, computer-based system such as New England Digital's Synclavier and Fairlight that used hard drives for media storage. Early DAWs were not only designed to play back sampled and/or synthesized sounds, but also to record, edit and play back digital audio tracks. They were also quite expensive. A key feature of DAWs was the ability to freely manipulate and play back recorded sounds. The user interfaces of each system were extremely different since the designers had no previous examples to refer to. This made the user learning curve quite intense especially for serious production or audio for picture applications. Today, most DAWs, especially computer-based DAWs, have MIDI recording, editing, and playback capabilities.

With the extinction and replacement of the early DAWs with much cheaper keyboard "workstations" the term "DAW" has evolved and now refers to a "virtual studio" software program, generally consisting of a combination of audio multitrack and MIDI software, host computer and audio interface hardware — the latter including an audio converter unit for analog-to-digital (ADC) and/or digital-to-analog (DAC) signal conversion, and sometimes a DSP system for processing digital audio externally from the host computer's own processing.

While most home computers with multitrack and editing software can function somewhat as a DAW, the term generally refers to computer systems which have professional audio software and high-quality external ADC-DAC hardware, usually with several discrete audio inputs and outputs. These professional quality audio interfaces offer sonic or functional advantages when compared to consumer soundcards, most notably by usually having lower latency (i.e. time between input of a sound and hearing it played back by the DAW). Besides having high-end sound cards, most DAWs also require a large amount of RAM, fast CPU(s) and sufficient free hard drive space. Some modern DAWs, in order to keep residual/background noise levels to a minimum in an audio monitoring environment, also feature a fanless power supply, a noise-suppressing hard disk enclosure and very quiet or passive CPU and system coolers.

Varieties

DAWs generally come in two varieties: computer-based and integrated.

Computer-based

A computer-based DAW has three components: a computer, an ADC-DAC, and digital audio editor software. The computer acts as a host for the sound card and software and provides processing power for audio editing. The sound card acts as an audio interface, typically converting analog audio signals into digital form, and may also assist in processing audio, and for playback converting digital to analog audio. The software controls the two hardware components and provides a user interface to allow for recording, editing, and playback. Most computer-based DAWs have extensive MIDI recording, editing, and playback capabilities. Some even have minor video-related features.

Integrated

An integrated DAW consists of a mixing console, control surface, audio converter, and data storage in one device. Integrated DAWs were more popular before personal computers became powerful enough to run DAW software. As computer power increased and price decreased, the popularity of the costly integrated systems dropped. However, systems such as the Orban Audicy once flourished in the radio and television markets. Today, some systems still offer computerless arranging and recording features with a full graphical user interface, such as the Roland VS series and MV-8000/MV-8800 and recent Mackie HDR-series hard disk recorders.

Common functionality

As software systems, DAWs could be designed with any user interface, but generally they are based on a multitrack tape recorder metaphor, making it easier for recording engineers and musicians already familiar with using tape recorders to become familiar with the new systems. Therefore, computer-based DAWs tend to have a standard layout which includes transport controls (play, rewind, record, etc.), track controls and/or a mixer, and a waveform display. In single-track DAWs, only one (mono or stereo form) sound is displayed at a time.

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.

DAWs are capable of many of the same functions as a traditional tape-based studio setup, and in recent years have almost completely replaced them. Modern advanced recording studios may have multiple types of DAWs in them and it is not uncommon for a sound engineer and/or musician to travel with a portable laptop-based DAW.

Perhaps the most significant feature available from a DAW that is not available in analogue recording is the ability to 'undo' a previous action. Undo makes it much easier to avoid accidentally permanently erasing or recording over a previous recording. If a mistake is made, the undo command is used to conveniently revert the changed data to a previous state. Cut, Copy, Paste, and Undo are familiar and common computer commands. As DAWs of all types involve specialised computer "engines" to run, they usually have these common computer commands too.

Commonly DAWs feature some form of automation, often performed through "envelopes". Envelopes are procedural line segment-based or curve-based interactive graphs. The lines and curves of the automation graph are joined by or comprise adjustable points. 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). Automation data may also be directly derived from human gestures recorded by a control surface or controller. MIDI is a common data protocol used for transferring such gestures to the DAW.

MIDI recording, editing, and playback is increasingly incorporated into modern DAWs of all types, as is Synchronization with other audio and/or video tools.

Early history

The earliest attempts at creating digital audio workstations in the 1970s and 80s were limited by factors such as the high price of storage, vastly smaller slower processing and disk speeds available. However by the late 1980s, a number of consumer level computers such as the Apple Macintosh and Atari ST began to have enough power to handle the task of digital audio editing.

Macromedia's Soundedit, with Microdeal's Replay Professional and Digidesign's "Sound Tools" and "Sound Designer" were used to edit audio samples for sampling keyboards like the E-mu Emulator II and the Akai S900, and soon went on to be used for simple two track audio editing and CD mastering purposes. In 1994, a company in California called OSC produced a 4 track editing-recorder application called DECK that ran on Digidesign's hardware system, and which was employed in the production of The Residents' "Freakshow" LP; this combination of audio software and hardware was one of the earliest examples of what we today would call a DAW.

Many major recording studios finally "went digital" after Digidesign introduced its Pro Tools software, modelled 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 (e.g. Pro Tools, Studer Dyaxis, Sonic Solutions). Around 1992, the first Windows based DAWs started to emerge from companies such as Soundscape Digital Technology (which was later acquired by Mackie then by SSL), SADiE, and Spectral Synthesis. All the systems at this point utilized dedicated hardware for their audio processing.

The first Windows based software-only product, introduced in 1993, was Samplitude Studio (which already existed in 1992 as an audio editor for the Commodore Amiga).

In 1996, German company Steinberg introduced Cubase VST, which could record and play back up to 32 tracks of digital audio on an Apple Macintosh without need of any external DSP hardware. Cubase not only modelled a tape-like interface for recording and editing, but also modelled the entire mixing desk and effects rack common in analog studios. This revolutionised the DAW world, both in features and price tag, and was quickly imitated by most of the other modern DAW systems we know today.Free and open source software

Audacity screenshot

There are many free and open-source software 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 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, previously 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.

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.
Macaw is a public domain source code music program that runs on Microsoft Windows. It features a large number of built in instrument synthesizers and effects, and it can load and play SoundFonts.
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 (LAD) mailing list is a major driving force in developing standards, such as the LADSPA plugin architecture, for free and open systems. The Virtual Studio Technology (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.

External links

Introduction to DAW by Mitch Gallagher at Sweetwater Sound.
"Workstation Blues", an article about DAW systems (circa 1990) by Roger Nichols
WikiRecording's Guide to Digital Audio Workstations (DAWs)
A list of software DAWs, Sequencers, Hosts, etc.

jfn home recording & guitar

June 2, 2010

About Digital audio workstations