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Revel in-wall speaker measurements…spinorama, in room, Audysey XT32

Tangband

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When the driver is flush with the baffle (or wall), there are no concerns of early reflections from the same wall. The wall acts and approaches an infinite baffle and there will be no delays of concern. (And SIBR effects in the bass region are clearly audible, so I do not agree that they are much less disturbing.)

Speakers placed at a distance from the wall benefits from wall damping to reduce SIBR effects and reflections higher in frequency that could disturb stereo imaging.

Speakers placed far from the wall will have less problems, since the power of the reflected vs. direct sound will decrease. However, most of us do not have such large distances in rooms. Distance to wall is not related only to the 2 ms window affecting stereo imaging, but a much broader time window where the wall gives an artificial reverberation and sameness of music masking the "true" reverberation present on the recording. Some like the effect since it may give more "depth" - but again, musicians are not normally lined up two dimensions in front of a wall, but placed in three dimensions in a room.

Without multiple speakers and multi-channel recordings that may give hint of "being there", you may rely of seeing you room as a lounge with an open side against the room where the musicians are playing. Thus, the wall of the speaker, being both a friend and a foe, needs to "disappear". The Carlsson speakers are one compromise, in-wall speakers another.
Some of the things you are writing is not correct.
The high frequency reflections on the wall with inwall loudspeakers are VERY problematic for sound quality. You really have to put acoustic material on the wall, around the loudspeaker.
Thats exactly the way Carlsson oa50 and oa52 and oa61 loudspeaker works.
Without the damping material, the sound will be terrible.
B35B79A2-09A4-4042-A5F3-5CA8E2B5DF10.jpeg
 

abdo123

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Some of the things you are writing is not correct.
The high frequency reflections on the wall with inwall loudspeakers are VERY problematic for sound quality. You really have to put acoustic material on the wall, around the loudspeaker.
Thats exactly the way Carlsson oa50 and oa52 and oa61 loudspeaker works.
Without the damping material, the sound will be terrible.
View attachment 141027

how would the high frequencies hit (and reflect from) the wall if they're moving away from the wall?

Also that speaker in the picture is not an infinite baffle.
 

Thomas_A

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Some of the things you are writing is not correct.
The high frequency reflections on the wall with inwall loudspeakers are VERY problematic for sound quality. You really have to put acoustic material on the wall, around the loudspeaker.
Thats exactly the way Carlsson oa50 and oa52 and oa61 loudspeaker works.
Without the damping material, the sound will be terrible.
View attachment 141027
The Carlsson speakers are not in-wall, they are off-the wall, hence you benefit with damping.
 

redshift

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Some of the things you are writing is not correct.
The high frequency reflections on the wall with inwall loudspeakers are VERY problematic for sound quality. You really have to put acoustic material on the wall, around the loudspeaker.
Thats exactly the way Carlsson oa50 and oa52 and oa61 loudspeaker works.
Without the damping material, the sound will be terrible.
View attachment 141027

Apparently the damping panels are called “elephant ears”. Not sure why though?

1626257236924.jpeg
 

Thomas_A

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Allison speakers were also one type of speaker with ideas similar to the Carlsson.

https://www.audioholics.com/news/a-tribute-to-roy-f.-allison

I myself use near-wall DIY speakers with damping behind. In-wall speakers are just not possible in the apartment.

The Bremen speakers would be really nice "dream", but then with the three-speaker setup, center and side speaker configuration. Also not possible in my current room due to the constraints of windows and doors.

http://www.bremen.se
 

redshift

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Allison speakers were also one type of speaker with ideas similar to the Carlsson.

https://www.audioholics.com/news/a-tribute-to-roy-f.-allison

I myself use near-wall DIY speakers with damping behind. In-wall speakers are just not possible in the apartment.

The Bremen speakers would be really nice "dream", but then with the three-speaker setup, center and side speaker configuration. Also not possible in my current room due to the constraints of windows and doors.

http://www.bremen.se

Pictures of your speakers or it didn’t happen.
(Stated in jest)
:)
 

Thomas_A

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The panels are on the wall and speakers as close as possible to these. Ideally I would like larger panels, but this is what is allowed (WAF).

With respect frequency response, left speaker 20 Hz-20 kHz at 50 cm distance from speaker (green) and at LP (about 3 meter). Quite smooth sounding, laid-back. Subjectively, I like them, tweeter is tuned down by ear about 1 dB from original filter.

v%C3%A4nster.png
 
OP
Bear123

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@Bear123 - can I ask, are the speakers just sitting in the cavity with the front attached to the gyprock? What size/depth cavity space do you need?
Yes the speakers are mounted with the factory fasteners directly to the wall cavity….the wall surface is lathe and plaster. In case you aren't familiar:
Lathe and Plaster
I don't know what size is *needed*, but, I assume that the wall cavity is probably quite large compared to a typical bookshelf speaker. I assume this probably simply results in "free" low frequency efficiency. Does this help or matter with an 80 Hz crossover? Not sure.
 
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Trouble Maker

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@Bear123 did the 'tabs' to hold the speaker in work with your walls?
Ours are lathe and plaster also, and some with paneling over them. It's caused issues with some electrical 'old work' boxes not having enough range of depth on those tabs/ears for the total thickens of the late/plaster/paneling.
 
OP
Bear123

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I was not home for the holes being cut or for the speakers being installed. Haven't taken them out to check. I've taken the magnetic grilles on and off several times, and they attach quite firmly. Haven't noticed the speakers being loose anywhere when doing this. I do have a somewhat significant difference in extension between one and the other so not ruling out the possibility that one may not be sealed well. There could be other causes as well.
 

nathan

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I'd guess it is not about how well sealed they are if they both feel pretty solid. That large a difference would have to be caused by a large opening if an opening is the cause.

I would surmise there is a small possibility that the internal cavity is quite different between the two, but they seem to be designed to work consistently with "regular" stud bay dimensions that could vary from 1 to 3 cubic feet.

Some of the higher end in wall Revel's specific things like being 2/3 of the way between the top and bottom of the cavity, in order to minimize problematic internal resonances. But even those wouldn't seem to explain what you are seeing.

I would be most inclined to suspect it is the difference in boundaries around the speakers, and that using EQ to tamp down the peaks will yield excellent results. Seems like you are on that path.
 
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