Home Theatre Speaker Install Question

[SomeGeoffGuy]

So a buddy of mine is designing a home theater room above his garage. It is a 3 stall garage, so the room is pretty big - but the end of the garaged has a sloped roof. The room ends up being about 23 x 17 with a 7.5 foot ceiling. The end with the sloped roof is being walled off and it will have a triangular crawl behind it for HVAC and some built shelves and things.

The question is - can you build speaker alcoves for the front three speakers without messing up your sound? He wants towers with a large center up front as well as one or two Rel HT subs. (the four surround and four Atmos will most likely be architectural built-in speakers). He was originally looking at Paradigm speakers, but they have rear ports and I told him they might sounds funny in a 5 sided wood alcove. There are a couple brands (Focal, Elac) with front ports and of course Magico is fully sealed (Only $14k for A1's and a center channel!), so I pointed him that way for now.

I was just wondering if anyone could share some thoughts and experiences with speaker alcoves. Will front port solve the issue?

Thank you.

-Geoff