High Definition Audio

Integrated Audio for Today and Tomorrow

Intel has worked with the industry to develop a new specification for integrated audio that is capable of delivering the features and high-end performance of an add-in audio card. Intel® High Definition Audio (Intel® HD Audio) is capable of playing back more channels at higher quality than previous integrated audio formats. In addition, Intel High Definition Audio has the technology needed to support the latest and greatest audio content. By enabling enhanced usage models, Intel High Definition Audio, available with the Intel® Express Chipsets, will also change how computer users interact with sound.

The Challenge to Find Better Audio

When AC‘97 was initially developed, users were typically listening to only music and movies with stereo sound. With the success of DVD movies encoded with Dolby* Digital and DTS* multi-channel audio formats, users have become accustomed to listening in full surround sound with anywhere from six to eight speakers. While AC‘97 technology has struggled to keep pace with all these advancements, Intel High Definition Audio is designed specifically for the high-quality multi-channel audio experiences. Newer audio and video encoding/decoding algorithms also enable a higher-quality listening experience. More and more consumers are moving their computers into the living room or family room so they can enjoy digital music or movies throughout the house on state-of-the-art multi-channel audio systems or big screen TVs. With better speakers connected to their computers, the limitations of current computer sound subsystems, whether integrated or add-in, can degrade the overall digital experience. Many consumers are also asking for the ability to play two different audio streams through their PC at the same time-perhaps classical music in the study and a movie in the living room. These demands cannot be met with previous audio solutions.

An Outstanding Audio Experience

Intel HD Audio delivers significant improvements over previous generation integrated audio and sound cards. Intel HD Audio hardware is capable of delivering the support and sound quality for up to eight channels at 192 kHz/32-bit quality, while the AC‘97 specification can only support six channels at 48 kHz/20-bit. In addition, Intel HD Audio is architected to prevent the occasional glitches or pops that other audio solutions can have by providing dedicated system bandwidth for critical audio functions.

Innovative Uses for the Digital Home

Dolby Laboratories* selected Intel HD Audio to bring Dolby-quality surround sound technologies to the PC, as part of their recently announced PC Logo Program. The combination of these technologies marks an important milestone in delivering quality digital audio to consumers. Intel HD Audio is able to support all the Dolby technologies, including the latest Dolby Pro Logic* IIx, which makes it possible to enjoy older stereo content in 7.1 channel surround sound. The Dolby PC Entertainment Experience is available exclusively on Intel-based PCs, including the Intel® Pentium® 4 Processor with Hyper-Threading (HT) Technology† or Intel® Pentium D Processor combined with the Intel® Express Chipset Family with Intel® High Definition Audio. The Express Chipset family includes:

Intel® 955X, 945G and 945P Express Chipsets Intel® 925XE and 925X Express Chipsets Intel® 915G, 915P, 915GV, 915GL, 915PL Express Chipsets Intel® 910GL Express Chipset

Consumers also want the ability to play back two different audio tracks, such as a CD and a DVD simultaneously, which can’t be done using current audio solutions. Intel HD Audio features multi-streaming capabilities that give users the ability to send two or more different audio streams to different locations at the same time, from the same PC. Send a DVD movie with 5.1 audio to a surround sound system in the living room, while you listen to digital music and surf the Web on the PC. Microsoft* has chosen Intel HD Audio as the main architecture for their new Unified Audio Architecture* (UAA), which provides one driver that will support all Intel HD Audio controllers and codecs. While the Microsoft driver is expected to support basic Intel HD Audio functions, codec vendors are expected to differentiate their solutions by offering enhanced Intel HD audio solutions. The result is high-quality PC based audio that delivers a seamless convergence of digital entertainment between the PC and consumer electronic devices. Enhanced Features Intel HD Audio also enables enhanced voice capture through the use of array microphones, giving users more accurate speech input. While other audio implementations have limited support for simple array microphones, Intel HD Audio supports larger array microphones. By increasing the size of the array microphone, users get incredibly clean input through better noise cancellation and beam forming. This produces higher-quality input to voice recognition, Voice over IP (VoIP), and other voice-driven activities. Intel HD Audio also provides improvements that support better jack retasking. The computer can sense when a device is plugged into an audio jack, determine what kind of device it is, and change the port function if the device has been plugged into the wrong port. For example, if a microphone is plugged into a speaker jack, the computer will recognize the error and can change the jack to function as a microphone jack. This is an important step in getting audio to a point where it ‘just works‘-users won‘t need to worry about getting the right device plugged into the right audio jack. The Solution for the Future Designed for “glitch-free” audio playback, multi-streaming, jack retasking, and UAA support, Intel HD Audio offers an audio solution for years to come. As one of the many new technologies introduced with the Intel® 955X, 925, 915, and 910 Express chipset family, and now the Intel® 945 Express chipset family, Intel HD Audio enhances the end-user experience and enables the convergence of digital entertainment for both PCs and Consumer Electronics (CE) products. † Hyper-Threading Technology requires a computer system with an Intel® Pentium® 4 processor supporting Hyper-Threading Technology and an HT Technology enabled chipset, BIOS and operating system. Performance will vary depending on the specific hardware and software you use. See http://www.intel.com/info/hyperthreading/ for more information including details on which processors support HT Technology. Some HD Audio functionality is dependent on actual implementation, controller, and codec. Intel® Pentium® and Pentium® D processors, and 955 Express chipsets may contain design defects or errors known as errata which may cause the product to deviate from published specifications. Current characterized errata are available on request.