You are not logged in. [Log In]


Forums » General Discussion » Home Theater » Thoughts on M3 in-ceiling transparency

Page 1 of 4 1 2 3 4 >
Topic Options
Rate This Topic
#432993 - 08/14/19 10:25 PM Thoughts on M3 in-ceiling transparency
rrlev Offline
veteran

Registered: 09/25/09
Posts: 198
Loc: Boston Area
In a conversation with Ian a little while back I found out that the M3 in-ceiling speakers were not totally transparent. To create a speaker flush with the ceiling required the speaker to be recessed behind the flange, and apparently, this gives enough clues for us to know where the sound is coming from. (note this is probably true for all in-ceiling speakers)

My first reaction was dismay … But thinking about it more I decided that in most cases you really should not care.

First let’s look at why anyone would care. If you are in the sweet spot of a decent stereo setup ... instruments and vocals should be coming from where the recording engineer placed them and not the obvious source (the speaker). Now with a conventional set of speakers you’d sit between them and typically somewhere around the same distance from the speakers as they are from each other to get this sound stage. Get too far left, right, close, or far and the stage will get muddied or collapse.

Now let us think for a minute about ceiling speakers. First off they are already compromised as they are … wait for it… on the ceiling. I’m really not that concerned with the sound stage coming from above as I am about not being in the same plane as the speakers are firing. Very rarely are you standing right below them. So right off the bat the speakers are not firing at you as they would if a pair was sitting on the floor. Next if one thinks about how far from the speakers our ears are … we are much closer to the ceiling than we would typically be from a stereo setup on the floor. For example if the ceiling speakers were 10’ apart and our ears were at 5’ the we’d need a 14+’ ceiling while standing directly below them to be in the middle of the sweet spot. If your ceiling is 8’ high you might be hard pressed to find a sweet spot if you were standing. So even if a ceiling speaker could image well in most cases you might not be able to take advantage of it …

Now, “does it matter?”

For background music, in your dinning room, hallway, or anywhere else your not going to be sitting consciously listening for the stage it’s not going to matter.

As a 5.1 or 7.1 surround speakers they are a poor substitute for any of the QS speakers (which give a field of sound you can not localize) but if aesthetics are an overriding factor it will probably do an ok job at giving you the surround effects. One might note that even if you could localize where it came from, while the movie is playing your concentration is elsewhere.

In an ATMOS system you’d like your speakers to image smoothly as objects fly around you but you are also limited by your ceiling height. So if you have high ceiling you might consider using the M3 in-wall or on-wall versions (which can be transparent). But for most of us with ceilings 9’ and under the in-ceilings would probably not be any worse.

The only other case I can think of is that these are your main speakers … in that case you ether don’t care about imaging or you made a very poor choice.

Bottom line ... if your creating a ATMOS theater and have 11' ceiling you might steer away from the in-ceilings. In all other cases they are probably be just fine.
Thoughts?

Top
#432994 - 08/15/19 03:44 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
nickbuol Offline
axiomite

Registered: 09/16/04
Posts: 5370
Loc: Marion, IA
I have had an Atmos (7.1.4 with dual subs) setup for 3.5 years now. I have a ceiling that is below the desired Dolby spec at just under 8 feet tall. My only real option for good sound dispersion and coverage were to ceiling mount "on-wall" M3s using Axiom FMBs so that I could get the correct angle forward and back and be able to point the speakers towards the listening area. Works amazingly well and I've be in a good number of Atmos demo rooms at CEDIA since 2014 when Atmos was announced for home use.

Now, in-ceiling M3s have an aimable tweeter that helps to get better overhead imaging, but for really low ceilings, you still need the sound to be able to hit all of the seats, so to speak.

So in actuality, the further away the speaker, the more dispersion that it creates by the time it hits the listening area. The closer, then the less dispersion.

If in-ceiling speakers have a lower dispersion than regular or "surface mounted" like my on-walls, then you would actually want to only use them in high ceiling applications (ok, higher than my 7ft 10in ceiling, lol) as they would have enough sound dispersion at a lower ceiling distance.

Keep in mind that Atmos speakers are often referred to as "overhead speakers" when they should never truly be "overhead." They should be 35 - 50 degrees in front or behind the main listening area. That is why you wouldn't want something that is a tad more "laser focused" at those angles on a lower ceiling.


With all of that said, I have no idea as to the sound dispersion capabilities of Axiom in-ceiling speakers. If they are wide enough, the math may work out in one "lower ceiling" room vs another. For me, I had 2 reasons for going on-wall but mounted to my ceiling... 1) I have a lot of soundproofing technology in my room construction (and acoustical treatments, but those are movable). I would never be able to find locations for in-ceiling speakers that wouldn't hit a ceiling joist or hat channel or both that would fall within Dolby spec, even if I did, retro-fitting in-ceiling speakers would massively compromise my soundproofing. Additionally, I wanted the best Atmos sound I could get with Axiom speakers, so I needed a no-compromise approach with the speaker type and installation, that meant on-walls angled towards the MLP.

So that is what I did and it is outstanding.

Here is some additional information from an actual professional about angling speakers for lower ceilings due to Atmos dispersion requirements...
DOLBY ATMOS: DISPERSION REQUIREMENTS FOR CEILING SPEAKERS
_________________________
2-M60s, VP180, 8-M3s, SVS 20-39PCi, DIY Sub, 8-Shakers, JVC RS45, Anthem MRX-1120

Top
#432995 - 08/15/19 06:27 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
Mojo Online   content
axiomite

Registered: 01/21/07
Posts: 6282
An in-ceiling M3, installed 52" above the plane of the ears, projects a pristine disc of sound from its tweeter, onto that plane, that is 5 feet in diameter. So if you're sitting right under it, the area 2.5 feet all around you is getting illuminated with linear highs.

The sound actually projects much wider than that but it becomes less linear as you move further out.

The mids and lows project even more than the highs.

The diameter of the disc grows in direct proportion to the height of the M3. With 11 foot ceilings, the diameter is 10 feet.
_________________________
A-LFR/1000-8/500v4x2 coming
1000-2,3,1500-3
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)

Top
#433009 - 08/16/19 07:44 PM Re: Thoughts on M3 in-ceiling transparency [Re: nickbuol]
rrlev Offline
veteran

Registered: 09/25/09
Posts: 198
Loc: Boston Area
Nick has an interesting point. Being able to aim your speaker when you have a low ceiling. I'm using a mix of height and top surround speakers in my setup*. The heights are M3 bookshelfs and the tops are M3 on-walls. I passed on the M3 ceiling speakers for a few reasons:

1) Wanted to be move them if needed. This included an option of being able to setup my screen on the long or short walls.
2) Didn't want to put a hole in my ceiling (like Nick ... there is a lot of expense which went into soundproofing).
3) Ability to aim the speakers (heights on a FMCB and I was not quite sure how I was mounting the tops but if Nick vouches for the FMB for the on-walls that may be the way to go).
4)Transparency was the only other reason but as my post states (I'm not sure it matters)



*The mix of heights and tops were carefully picked to work with ATMOS, DTS-X, and Auro-3D.

Top
#433012 - 08/16/19 08:17 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
rrlev Offline
veteran

Registered: 09/25/09
Posts: 198
Loc: Boston Area
On-walls, I assume use the wall to reinforce the base frequencies. So, The FMB mounting of on-walls leads to some questions ...

1) is that assumption correct
2) how far from the wall can one get before you hear a difference
3) Is the distance of an FMB ok?
4) Does tilting it in various directions change the sound ...

Top
#433014 - 08/16/19 10:25 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
Mojo Online   content
axiomite

Registered: 01/21/07
Posts: 6282
You also need to be concerned with driver center line to side wall distance, driver center to floor distance, cabinet baffle width and the dimensions of your room. Just sayin' that the response of speaker boundary interference is more complex than just the distance of the FMB.
_________________________
A-LFR/1000-8/500v4x2 coming
1000-2,3,1500-3
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)

Top
#433015 - 08/16/19 10:28 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
Mojo Online   content
axiomite

Registered: 01/21/07
Posts: 6282
Then you also have floor and ceiling bounce. LOL!
_________________________
A-LFR/1000-8/500v4x2 coming
1000-2,3,1500-3
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)

Top
#433016 - 08/16/19 10:29 PM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
Mojo Online   content
axiomite

Registered: 01/21/07
Posts: 6282
And multiple drivers to contend with in all these speakers. Time to give up and just listen.
_________________________
A-LFR/1000-8/500v4x2 coming
1000-2,3,1500-3
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)

Top
#433020 - 08/17/19 04:00 AM Re: Thoughts on M3 in-ceiling transparency [Re: Mojo]
rrlev Offline
veteran

Registered: 09/25/09
Posts: 198
Loc: Boston Area
Originally Posted By Mojo
And multiple drivers to contend with in all these speakers. Time to give up and just listen.
mojo you are confusing the issue. I’m asking at a simple question on mounting a on wall speaker. Your multiple posts are the equivalent of spam and are not helpful.

Top
#433021 - 08/17/19 07:28 AM Re: Thoughts on M3 in-ceiling transparency [Re: rrlev]
Mojo Online   content
axiomite

Registered: 01/21/07
Posts: 6282
It's not a simple question as I've pointed out. smile
_________________________
A-LFR/1000-8/500v4x2 coming
1000-2,3,1500-3
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)

Top
Page 1 of 4 1 2 3 4 >

Moderator:  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 
Forum Stats

15,347 Registered Members
16 Forums
24,213 Topics
428,457 Posts

Most users ever online:
883 @ 03/04/17 05:06 PM

Top Posters
Ken.C 18044
pmbuko 16437
SirQuack 13625
CV 11735
MarkSJohnson 11445
4 registered (Mojo, BBIBH, SRoode, SirQuack)
189 Guests and
3 Spiders online.
Key: Admin, Global Mod, Mod
Newsletter Signup