April Meeting Notice

 

April 2007 Meeting Notice

Subject:

Dolby Lake Processor

Speaker(s):

David McGrath

Place:

Dolby Labs, San Francisco

Time and Date:

April 24th, 7:30 PM (refreshments at 7:00 PM)

Description

After the final mix is produced at the output of a mixing console, a significant amount of processing is applied before the audio is fed to the power-amplifiers and speakers in a large-scale sound system. In the past, the speaker controllers used for a typical large PA were kept simple, because the topology of the sound-system did not require excessive controllability. When required for more advanced systems, the speaker controllers were augmented with equalizers and delay lines to allow for higher levels of control. Recent advances in technology (particularly line-array spaaker systems), and higher expectations from the audience, have led to an ever-growing requirement for more advanced control of the sound system.

The talk will cover the typical requirements of such a sound system, and describe how the development of the Dolby Lake Processor has atempted to address these requirements. The Dolby Lake Processor's design will be described, including the analog interfaces, multi-channel hardware-based sample-rate conversion, a new equalizer methodology, linear-phase crossover structures, and the innovative network-based control interface.


About the Speaker

David McGrath graduated from the University of Sydney in 1986, with a Bachelor of Science and a Bachelor of Electrical Engineering degree. He was an integrated circuit designer for 5 years, and then went on to be a
founder of Lake DSP in 1991. At Lake, David was part of a team that built the Huron Digital Audio Workstation, which became a standard piece of equipment for researchers in acoustics, virtual reality, car acoustics, and many other esoteric fields. In 1997, David joined with Clair Brothers and live sound legend Bruce Jackson, to develop a new speaker controller for live PA systems. Lake was acquired in 2004 by Dolby Laboratories, and David is now part of the Research group at Dolby Australia. The live-sound group at Dolby Australia continues to operate
under the leadership of Bruce Jackson, and David continues to be involved in the development of new live sound products.

Address:
Dolby Laboratories
100 Potrero Avenue
San Francisco, CA 94103-4813
415-558-0200

Directions

 http://www.dolby.com/company/directions_sf.html

From Peninsula/S.F. Airport/Silicon Valley (Hwy. 101 North) Take Vermont Street Exit. Make immediate left onto Vermont Street. Go 5 blocks and turn left onto Alameda Street. Three blocks up is Potrero Avenue. Dolby is the large, red, 3-story brick building on the corner of Potrero and Alameda.

From Bay Bridge (Hwy. 80 West) Take 9th Street/Civic Center exit. Go to the south onto Harrison Street. Follow Harrison to 10th Street. Turn left onto 10th Street and proceed under freeway overpass onto Potrero Avenue. Dolby is the large, red, 3-story brick building on the corner of Potrero and Alameda.

From Golden Gate Bridge (Hwy. 101 South) Cross Golden Gate Bridge, take the Lombard Street (Hwy. 101) Exit. Follow Hwy. 101 signs up Lombard to Van Ness Avenue. Turn right. Proceed on Van Ness to Fell Street and turn left. Proceed on Fell until it crosses Market Street and becomes 10th Street. Continue on 10th under freeway overpass and bear right onto Potrero Avenue. Dolby is the large, red, 3-story brick building on the corner of Potrero and Alameda.