Library
An Introduction to Electromagnetic Compatibility (EMC) and Electromagnetic Interference (EMI) for Audio Systems Designers
This paper, intially published in 1989, was recently presented again to the Audio Engineering Society (AES) and continues to serve as an authoritative source of information on the subject.
Electromagnetic compatibility and electromagnetic interference engineering are well-developed field. This paper reviews many of the concepts and techniques used by professionals in this discipline, to help audio system designers understand why many of the techniques used in audio engineering exist. It will also put them in a better position to make further use of these techniques in difficult situations and new designs.
Audio for Committee Rooms – Canada’s House of Commons
by Jeff Bamford
To properly implement a long-term solution for integrating technology into committee rooms, a prototype committee room was built. This unique opportunity allowed many facets of the room to be tested and configured. This was especially important for determining the accommodation requirements for multimedia devices in the room, such as television cameras and large-screen projection.
This paper reviews the approach to providing audio services for Canada’s House of Commons Committee Rooms. See also the description of the House of Commons Master Control project.
Taking Down the Walls of Distance Education
by Alan Hardiman
An extraordinarily innovative high definition video conferencing system linking 19 sites at Dalhousie University, the University of New Brunswick and four hospitals uses large amounts of custom software, microphone queuing across multiple sites with associated camera control, and a high speed network to offer all students a comparable learning experience, regardless of their location hundreds of kilometres apart.
See also the description of the Dalhousie University, Faculty of Medicine project.
Crestron DigitalMedia™ Brings High-Definition Content to Dalhousie Medicine New Brunswick Program
Engineering Harmonics worked closely with Crestron while developing custom control software for Dalhousie to permit extensive routing from a variety of digital video sources to various combinations of displays throughout the network. Crestron DigitalMedia™ was installed as the single-platform solution to manage, control and distribute multimedia technology throughout the facilities on two campuses in different provinces.
See also the description of the Dalhousie University, Faculty of Medicine project.
Sharing the World Stage with Gehry at Bard College
by Alan Hardiman
World-class knowledge and home-town service, two unlikely bedfellows, played no small role in the successful completion of one of the foremost performance spaces in the world. Designed by acclaimed architect Frank Gehry, the Richard B. Fisher Center for the Performing Arts at Bard College in upper New York State has garnered rave reviews.
See also the description of the Bard College project.
SkyDome (now Rogers Centre) Acoustical Model
by Jeff Bamford
In 1996, Engineering Harmonics was retained to investigate, test and re-tune the sound system for Toronto’s SkyDome (now Rogers Centre). On the basis of this work and insight into the sound system, SkyDome retained Engineering Harmonics to prepare cost estimates and a plan to upgrade the systems. Engineering Harmonics subsequently implemented a project to upgrade, replace and improve the system. The project involved the replacement and addition of loudspeakers, replacement of amplifiers and implementation of a digital audio transportation and DSP system.
This paper discusses the EASE computer model used to model the new loudspeakers for the lower two tiers of seating. See also the description of the Skydome (now Rogers Centre) project.
Timeless Classics
Grounding Systems and Their Implementation
by Philip Giddings and Charles Atkinson
The isolated star ground system is the most popular implementation of technical grounding for the purposes of grounding sensitive electronic equipment. This approach has been in practice for many years, and while it is not a perfect solution, it is the solution that presents the least compromises.
This paper documents the current approach as implemented in a number of large installations and is part of an on-going AES effort to document appropriate practices with regard to the control of noise in audio systems.
Power and Ground Update
This article provides some ideas and developments that affect electrical noise in audio and other technical systems. Anyone planning a new facility or a renovation will want to consider how these can best be used to maximize and protect their investment.
Noise Reduction Systems
Noise reduction techniques are not new, however they take on new importance in an
increasingly demanding and educated market place.
This article discusses a number of established, well known single-ended noise reduction
products. (Single-ended products are only used during playback and this differentiates them
from double ended or encode/decode devices used in both recording and playback.)
A New and Important Audio Equipment Evaluation Criteria
This paper outlines a simple but seemingly overlooked source of noise in systems, referred to as the Pin 1 Problem.
(Hint: check the equipment grounding.)
