Originally Posted by Augerhandle
It's all about the angle (taken care of by the installer), and the delay set for distance (taken care of by room correction).
? Does that mean you had someone else do it?
The helicopter will move downward when it goes between the higher speaker and the lower speaker.
No, it won't.
If you don't think having front heights at 96", top middles at 72" and rear heights at 96" won't result in that Dolby Atmos helicopter dipping downward and then climbing back up as it moves around the room, that means you've NEVER TRIED IT. I guarantee you 100% it will exactly that! This is why overheads are normally installed at the same height as each other (bed speakers too). It's also how I can do dialog height with a mixer by changing the virtual height of the dialog to move upward from bed level to mid-screen level by mixing overhead with bed level. The angle changes typically by the distance from the listener, not physically different heights, particularly near the listener (i.e. mid-room speakers near the MLP).
Normally, you'd need side heights to even have the top middle location at a different height than the rest, but a bulkhead or beam can easily force a speaker into a different height position (clearly the case here). It's quite easy to hear differences in distance even with the same overhead angles. There's a huge difference between a person talking at 10 feet away and one at 100 feet away, particularly when they're phantom imaging between speakers that are at different heights.
How do you think Atmos images things at different heights between bed level and height level? It phantoms in-between them. If you place the bed speaker higher, it can't image sounds lower. By moving the height of the speaker, you are moving the hard image with it. Phantoms only work in-between hard sources. So if the first source is 11 inches higher, the phantom image will start moving lower the moment in starts moving between the to locations and will end up right at the top middle (or whatever) speaker when the pan completes to that speaker. The sound is now coming from that speaker directly. It will sound like it's coming right from it at whatever height it's at. Thus, if a sound sound moves from one to the other, it will move in a diagonal line between the two. That means it will change height by that 11 inches by the time it gets there.
And my top middles (as side heights) were only off by 8 inches (due to a steel beam box not letting me mount that on the ceiling), not 24 inches and I could clearly hear the helicopter changing height as moved around the room. How could it not, would be the better question. By leaking some front/rear height, that arrayed the speaker and reduced the difference (in phantom height as a result) by about half, resulting in a helicopter that was no longer diving downward in the middle of the room. But with pure discrete and even larger differences, it would eventually start dive bombing in the middle.
Perhaps your installer
could verify this for you?