Yes they can. Maybe another ther 5-10 degrees. Even though they're angled I wouldn't put them much further than 10 feet away from the listening position. That's for my application which is a 5.1 home theatre. These for the R&L, center channel at head height below the TV and Monoprice Alpha 6.5 (non angled) for the rear channels. Sounds great for me and they're still warming up.
I have had these installed for roughly one week and so far so good. They are installed roughly 10ft from the listening position and I can't complain. The only negative is their sensitivity. My center channel was much louder but that can be fixed with some amp tuning. I am excited for them to "warm up" a bit as they are fairly stiff and the woofers don't move much. I have the them set at neutral attenuation and they aren't to bright for me. This helps them blend with my center channel too. Quality is great, instal was simple, great sound and overall I am happy with them.