Originally Posted by bubbrik
Question: what is the difference between the second set of surrounds and wides?
Wides would be supported by the AVR depending on the AVR you chose. Front wide/height speakers are discreet channels that can be supported with metadata from an authored Blu-ray, UHD Blu-ray.
An extra set of side surrounds will most likely will not be supported unless the AVR specifically says that it supports it.
The 16 channel processors that I referenced will or could support the extra side channels. The 16 channel and higher processors typically offer the ability to replicate a discreet channel for assessment. In this way you can add additional surround channels and retain control over them for Atmos execution. In this case the extra channel would be discreet, receive side channel information, and be calibrated for its specific location.
The typical 9.1.4 or below AVR's will not and are not typically designed to do the reassignment for side surrounds as it's not part of the Dolby spec and at that level of hardware, it's impracticable. Some AVR's in this range will allow you to select front or rear surrounds for assignment.
If you chose to implement the extra side surrounds as other's have suggested, wiring series or parallel to the side surrounds, you will have problems with room correction implementation and the Atmos "bubble" will not be as immersive. Atmos and object-oriented audio is about discreet channels not matrixed sound. Daisy chaining side surrounds is 1980's home theater audio. But, it's your decision.
Originally Posted by bubbrik
Is it based on their location or assigning them as wides in a receiver that explicitly supports wides or both?
It's both. The wide/height and Atmos speakers are designed to work with the bed speakers (5.1/7.1) to create an immersive 360° bubble of sound around you. As I said in an earlier post this is object-oriented audio. With the correct speaker location and careful setup with room correction, Dolby Atmos has the ability to create or project a sound cues in front, behind, above, below, or anywhere inside the bubble. In other words, Atmos setup done wright can project sound on 3 axis, X,Y,andZ.
Dolby Atmos in a commercial installation can support up to 128 audio tracks/channels with 64 speakers. Dolby Atmos for home can support 24.1.10, or 35 channels. There are home theater processors that are available now that support up to 32 channels. They cost around $30,000 and you need 32 amplifiers to go with it.
You should also understand that the metadata for Atmos is mixed into the audio presentation to match the installed speaker configuration. This is also true for DTS:X and Auro-3D. Blu-ray and UHD Blu-ray discs must be encoded with the necessary metadata before you will hear the extra speakers. So if the sound engineer mixed audio to come from front wide/heights and you've mounted them on the side of the room...
Blu-ray and UHD Blu-ray discs are authored/encoded as 5.1 and 7.1. The disc's will have to be furthered authored to support Atmos, DTS:X, and Auro-3D before your AVR will support the object-based mix. In other words if Atmos is not on the disc, it's not going to be coming our of your speaker.
Your plan to go 7.1.4 is more or less a minimum for Atmos.
You might want to spend some time reading about Dolby Atmos as you can get the information from the horses mouth vs. opinions on a forum: https://www.dolby.com/us/en/guide/do...tup/index.html
You're investing some money, might as well do it correct.