AES Section Meeting Reports

Pacific Northwest - May 26, 2009

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The May 2009 meeting of the PNW Section featured a description of the audio architecture of the Microsoft Windows 7 operating system by Jerry Smith, Senior Program Manager on the Windows 7 Sound Team. 11 AES members and 16 non-members attended, at the Microsoft Research building in Redmond, WA.

PNW Chair Steve Turnidge opened the meeting, and attendees introduced themselves. Section Vice-chair Rick Chinn mentioned the passing of local audio engineer John Ross. Meeting coordinator Ivan Tashev then introduced Jerry Smith.

Many of the audio changes in Windows 7 are not necessarily obvious to the end user, but operating system refinement and accomodation of desired new features. Thus, the discussion was perhaps more familiar to those versed in OS software development.

The Windows Universal Audio Architecture (UAA) had a major redesign for the Vista operating system including moving the audio stack from kernel mode to user mode and adding per-application volume controls. Windows 7 continues this audio evolution, now emphasizing "class driver" software instead of custom driver software for devices attached to a computer, and other features intended to accomodate current and future audio/video roles on the PC and provide a better interface for users.

To better integrate using audio devices such as personal music players, AV devices and telephony functions, Jerry described how Windows 7 improvements included better device role detection, stream switching ("my audio follows my device"), stream routing (as devices arrive/depart), improved latency, auto attenuation (ducking/reducing audio level when a higher priority signal occurs such as a phone call), HDMI (high definition multimedia interface) support, capture monitor (such as allowing your Zune to play over your PC speakers), and power management improvements (but not meant for mobile devices like phones).

The class driver situation was discussed, and the OS status at the meeting time was that the release candidate appeared in early May, and they were working with sound companies on final issues, posting white papers (for a qualified audience) and will plan to have multiple versions of Win7.

A break and prize drawing was held.

Next, PNW Committeeman Ivan Tashev outlined the upcoming PNW elections procedure and slate. Then, Jerry Smith fielded Win 7 Qs and As.

Full report at the PNW website,

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AES - Audio Engineering Society