Intel High Definition Audio
Encyclopedia
Intel High Definition Audio (also called HD Audio or Azalia) refers to the specification released by Intel in 2004 for delivering high-definition audio that is capable of playing back more channels at higher quality than previous integrated audio codecs like AC'97. During development it had the codename Azalia.
Hardware based on Intel HD Audio specifications is capable of delivering 192-kHz 32-bit quality for two channels, and 96-kHz 32-bit for up to eight channels. However, , most audio hardware manufacturers do not implement the full high-end specification, especially 32-bit sampling resolution.
Microsoft
Windows XP
SP3 and later Windows versions include a Universal Audio Architecture
(UAA) class driver which supports audio devices built to the HD Audio specification. There are UAA drivers for Windows 2000
and Windows XP SP2 as well. Mac OS X
has full support with its AppleHDA driver. Linux
also supports Intel HDA controllers, as do the OpenSolaris
, FreeBSD
, NetBSD
and OpenBSD
operating systems.
Like AC'97, HD Audio is a specification that defines the architecture, link frame format, and programming interfaces used by the controller on the PCI bus and by the codec on the other side of the link. Implementations of the host controller are available from at least Intel, Nvidia
, and AMD. Codecs which can be used with such controllers are available from many companies, including Realtek
, Conexant
, Analog Devices
(SoundMAX), Integrated Device Technology (IDT)
(acquired from SigmaTel
), VIA
, Wolfson Microelectronics
, and formerly C-Media
.
Hardware based on Intel HD Audio specifications is capable of delivering 192-kHz 32-bit quality for two channels, and 96-kHz 32-bit for up to eight channels. However, , most audio hardware manufacturers do not implement the full high-end specification, especially 32-bit sampling resolution.
Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
SP3 and later Windows versions include a Universal Audio Architecture
Universal Audio Architecture
Universal Audio Architecture is an initiative unveiled in 2002 by Microsoft to standardize the hardware and class driver architecture for audio devices in modern Microsoft Windows operating systems...
(UAA) class driver which supports audio devices built to the HD Audio specification. There are UAA drivers for Windows 2000
Windows 2000
Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
and Windows XP SP2 as well. Mac OS X
Mac OS X
Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
has full support with its AppleHDA driver. Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
also supports Intel HDA controllers, as do the OpenSolaris
OpenSolaris
OpenSolaris was an open source computer operating system based on Solaris created by Sun Microsystems. It was also the name of the project initiated by Sun to build a developer and user community around the software...
, FreeBSD
FreeBSD
FreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
, NetBSD
NetBSD
NetBSD is a freely available open source version of the Berkeley Software Distribution Unix operating system. It was the second open source BSD descendant to be formally released, after 386BSD, and continues to be actively developed. The NetBSD project is primarily focused on high quality design,...
and OpenBSD
OpenBSD
OpenBSD is a Unix-like computer operating system descended from Berkeley Software Distribution , a Unix derivative developed at the University of California, Berkeley. It was forked from NetBSD by project leader Theo de Raadt in late 1995...
operating systems.
Like AC'97, HD Audio is a specification that defines the architecture, link frame format, and programming interfaces used by the controller on the PCI bus and by the codec on the other side of the link. Implementations of the host controller are available from at least Intel, Nvidia
NVIDIA
Nvidia is an American global technology company based in Santa Clara, California. Nvidia is best known for its graphics processors . Nvidia and chief rival AMD Graphics Techonologies have dominated the high performance GPU market, pushing other manufacturers to smaller, niche roles...
, and AMD. Codecs which can be used with such controllers are available from many companies, including Realtek
Realtek
Realtek Semiconductor Corp. , a fabless IC design house situated in the Hsinchu Science Park, Hsinchu, Taiwan, was founded in October 1987, and subsequently approved as a listed company on the Taiwan Stock Exchange in 1998...
, Conexant
Conexant
Conexant Systems, Inc. is an American semiconductor company, formerly the semiconductor division of Rockwell International. Currently it's privately owned by Golden Gate Capital, an equity firm headquartered in San Francisco.-History:...
, Analog Devices
Analog Devices
Analog Devices, Inc. , known as ADI, is an American multinational semiconductor company specializing in data conversion and signal conditioning technology, headquartered in Norwood, Massachusetts...
(SoundMAX), Integrated Device Technology (IDT)
Integrated Device Technology
Integrated Device Technology, Inc. is a publicly traded corporation headquartered in San Jose, California, that designs, manufactures, and markets low-power, high-performance mixed-signal semiconductor solutions for the advanced communications, computing, and consumer industries. The company...
(acquired from SigmaTel
SigmaTel
SigmaTel is an electronics company located in Austin, TX, which designs mixed audio signal processors, and controller chips for multifunction peripherals. SigmaTel was Austin's largest IPO as of 2003 when it became publicly traded on NASDAQ...
), VIA
VIA Technologies
VIA Technologies is a Taiwanese manufacturer of integrated circuits, mainly motherboard chipsets, CPUs, and memory, and is part of the Formosa Plastics Group. It is the world's largest independent manufacturer of motherboard chipsets...
, Wolfson Microelectronics
Wolfson Microelectronics
Wolfson Microelectronics plc is a multinational microelectronics and fabless semiconductor company headquartered in Edinburgh, United Kingdom. It specialises in signal processing chips for the consumer electronics market and has engineering and sales offices throughout Asia-Pacific, Europe and the...
, and formerly C-Media
C-Media
C-Media Electronics, Inc. is a Taiwanese computer hardware company that manufactures processors for PC audio and USB storage, and wireless audio devices.-Products:-PCI audio:*CMI8338*CMI8738-SX*CMI8738-LX*CMI8738-MX*CMI8768...
.