Subjective evaluations of the digital high-definition television (HDTV) Gra
nd Alliance System were performed by the Advanced Television Evaluation Lab
oratory of the Communications Research Centre in Ottawa, Ontario. The overa
ll quality of the Grand Alliance System in both interlaced and progressive
modes was examined. Additional tests were conducted to assess the ability o
f the system to co-exist with NTSC and to support scan conversion at the re
ceiver. The system met or exceeded the specified requirements.