Help with rear speaker positioning with the Samsung Q990B.

Altecice · April 11, 2023

So the room I plan to use for my cinema is reasonably narrow so I am struggling to find the best placement for the rear speakers. I have the Samsung Q990B and the rear speakers have forward, sideways and up firing speakers built in.

I don't have the room to place the speakers behind the seating position very much (if at all). So my plan I guess would to be have them at 90'ish degrees from the central seating position or slightly behind the seating position -- check the image link below and feel free to offer advice. My main questions are as follows...

Is this the recommended way to place ATMOS rear speakers without space behind the couch?
What is the best rotation for the rears in this case? (facing forward towards my TV or tilted inwards to the central seating position, so that the main rear speaker faces the user, side speakers can bounce somewhat off the wall and the up firing can do their thing - as shown in my picture.)

*Any other advice about speaker or sub placement is welcome!

Many thanks!

https://imgur.com/a/r0H7mfb

edit: I might put the sub on the other side as that will allow the bass port maximum free air.

The lines coming from the rear speakers in my diagram show the direction of the front and side facing speaker.

tikker · April 11, 2023

I'd say position looks rather fine to me given your constraints. I'm not 100% sure if they recommend different positioning for these kind of sound bars, but speaking from "normal" surround setups the surrounds are usually more to the side of you than behind you. The rears are closer to behind you. For example, this is the Dolby spec for 5.1.4:

compared to 7.1.4 that includes rears:

4 hours ago, Altecice said:

Is this the recommended way to place ATMOS rear speakers without space behind the couch?

It's not like you have much other choice right? The Atmos aspect is more the upfiring parts and positional audio rather than the specific placement of speakers as you can see above. The non-Atmos versions of the setup would look the same, because the Atmos aspect (usually) doesn't come in until you start including upfiring or height/(in)ceiling speakers.

4 hours ago, Altecice said:

What is the best rotation for the rears in this case? (facing forward towards my TV or tilted inwards to the central seating position, so that the main rear speaker faces the user, side speakers can bounce somewhat off the wall and the up firing can do their thing - as shown in my picture.)

Position-wise I'd keep them where they are. As you can see from the drawings above, they should point towards the main listening position. I have no experience with these kind of things that fire from multiple sides, but I would experiment with just pointing the sides you have towards the centre of the room pointed at your orange dot in the middle of the couch and see how that sounds. At the end of the day it is about what sounds the best to you and gives you the most enjoyment.

Omon_Ra · April 12, 2023

8 hours ago, tikker said:

Position-wise I'd keep them where they are. As you can see from the drawings above, they should point towards the main listening position. I have no experience with these kind of things that fire from multiple sides, but I would experiment with just pointing the sides you have towards the centre of the room pointed at your orange dot in the middle of the couch and see how that sounds. At the end of the day it is about what sounds the best to you and gives you the most enjoyment.

Basically this. IIRC, those rears are semi-wireless, so it shouldn't be too hard to shift the position a bit to get it to sound right. Just keep in mind the surrounds will only be playing sound when there is audio being sent to that channel, so use some of the THX/Dolby audio/video tests, or parts of movies/TV shows with a lot of stuff going on in the surround channels, to see how the sound imaging is. The only thing I would be minorly concerned about is the side-firing parts of the surround speakers. If they're aimed very close to walls it could cause some strange bouncing effects off the walls which could be annoying.

As for the subwoofer, anywhere works really. Low frequencies are should be impossible to detect directionality, so anywhere you can plug it in and have it out of the way is usually sufficient. That's the nice thing with the wireless subs, you just need an outlet and you can put them wherever suits the layout of the room. Many recommend putting the sub in a corner, as the walls act as a quasi-horn, but the difference is marginal at best.

tikker · April 12, 2023

On 4/11/2023 at 3:45 PM, Altecice said:

edit: I might put the sub on the other side as that will allow the bass port maximum free air.

Forgot about the sub. I have it in a corner myself as well, but in principle you can do a sub-crawl to try and figure out optimal placement: https://www.svsound.com/blogs/subwoofer-setup-and-tuning/75365187-the-art-of-subwoofer-placement

Altecice · April 12, 2023

15 hours ago, Omon_Ra said:

Basically this. IIRC, those rears are semi-wireless, so it shouldn't be too hard to shift the position a bit to get it to sound right. Just keep in mind the surrounds will only be playing sound when there is audio being sent to that channel, so use some of the THX/Dolby audio/video tests, or parts of movies/TV shows with a lot of stuff going on in the surround channels, to see how the sound imaging is. The only thing I would be minorly concerned about is the side-firing parts of the surround speakers. If they're aimed very close to walls it could cause some strange bouncing effects off the walls which could be annoying.

As for the subwoofer, anywhere works really. Low frequencies are should be impossible to detect directionality, so anywhere you can plug it in and have it out of the way is usually sufficient. That's the nice thing with the wireless subs, you just need an outlet and you can put them wherever suits the layout of the room. Many recommend putting the sub in a corner, as the walls act as a quasi-horn, but the difference is marginal at best.

Yeah the side speaker close to the wall is a bit concerning but I can't exactly do much about it. I'm hoping the "spacefit sound+" feature may be able to compensate somewhat after bouncing test tones around and learning the layout of the room.

Thanks for your input, all.