Audio Stream Input/Output (ASIO) is a computer sound card driver protocol for

digital audio Digital audio is a representation of sound recorded in, or converted into, digital form. In digital audio, the sound wave of the audio signal is typically encoded as numerical samples in a continuous sequence. For example, in CD audio, sa ...

specified by

Steinberg Steinberg Media Technologies GmbH (trading as Steinberg) is a German musical software and hardware company based in Hamburg. It develops music writing, recording, arranging, and editing software, most notably Cubase, Nuendo, and Dorico. It also ...

, providing a low- latency and high fidelity interface between a software application and a computer's

sound card A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under the control of computer programs. The term ''sound card'' is also applied to external audio i ...

. Whereas

Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...

DirectSound DirectSound is a deprecated software component of the Microsoft DirectX library for the Windows operating system, superseded by XAudio2. It provides a low-latency interface to sound card drivers written for Windows 95 through Windows XP and can h ...

is commonly used as an intermediary signal path for non-professional users, ASIO allows musicians and

sound engineer An audio engineer (also known as a sound engineer or recording engineer) helps to produce a recording or a live performance, balancing and adjusting sound sources using equalization, dynamics processing and audio effects, mixing, reproduction, ...

s to access external hardware directly.

Overview

ASIO bypasses the normal audio path from a user application through layers of intermediary Windows operating system software so that an application connects directly to the

hardware. Each layer that is bypassed means a reduction in latency (the delay between an application sending audio information and it being reproduced by the sound card, or input signals from the sound card being available to the application). In this way, ASIO offers a relatively simple way of accessing multiple audio inputs and outputs independently.

Operating systems

Interface support is normally restricted to

Microsoft Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for serv ...

. Starting with

Windows Vista Windows Vista is a major release of the Windows NT operating system developed by Microsoft. It was the direct successor to Windows XP, which was released five years before, at the time being the longest time span between successive releases of ...

KMixer This article describes audio APIs and components in Microsoft Windows which are now obsolete or deprecated. Multimedia Extensions (MME) The MME API or the Windows Multimedia API (also known as ''WinMM'') was the first universal and standardized ...

has been removed and replaced by

WASAPI Windows Vista (formerly codenamed Windows "Longhorn") has many significant new features compared with previous Microsoft Windows versions, covering most aspects of the operating system. In addition to the new user interface, security capabilities ...

and a new

WaveRT Windows Vista (formerly codenamed Windows "Longhorn") has many significant new features compared with previous Microsoft Windows versions, covering most aspects of the operating system. In addition to the new user interface, security capabilities, ...

port driver. There is also an experimental ASIO driver for

Wine Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are m ...

, WineASIO, for a Windows compatibility layer for Linux. WineASIO driver uses the

JACK Jack may refer to: Places * Jack, Alabama, US, an unincorporated community * Jack, Missouri, US, an unincorporated community * Jack County, Texas, a county in Texas, USA People and fictional characters * Jack (given name), a male given name, ...

sound server as its audio back-end and allows many ASIO-aware applications to run with low latency under WINE. Other free or open source alternatives are ASIO4All, FlexASIO, ASIO2KS, and ASIO2WASAPI. Being a proprietary protocol, it does not have any universal compatibility with Windows-based

DAW Daw or DAW may refer to: People and language * Daw (given name) * Daw (surname) * Daw, an honorific used in Burmese name#Honorifics, Burmese names * Dâw people, an indigenous people of Brazil * Dâw language, a language of Brazil * Davaoeño lang ...

and other recording software. For example, the user manual of the Audacity audio editor states: "Licensing restrictions prevent us including ASIO support in released versions of Audacity, but Audacity can be compiled with ASIO support for private, non-distributable use."

References

External links

Steinberg website
{{DEFAULTSORT:Audio Stream Input Output Application programming interfaces Audio libraries Digital audio

Overview

Operating systems

See also

References

External links