Ontario Acoustic Supply (OAS) is Canada's oldest and largest single source distributor of acoustical ceilings, wall panels and grid products. Our niche strategy has given us the expertise to handle all types of projects, not only in Toronto but overseas as well.. OAS distributes Canadian Gypsum grid and ceilings and is the largest single source distributor of these products in Canada. As part of The Signature Group, OAS keeps in touch with markets not only in Canada but throughout the U.S. more... See more text