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

Tangband

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there will be no reflections, the wall the speaker is mounted on becomes the baffle.
You are absolutely right about that the whole wall becomes the baffle. And it will reflect sound at all frequencys, early reflections sounds really bad if its in the midrange and tweeter area.
Thats the main reason why conventional loudspeakers always gain clarity in midrange and tweeter area if they are moved from the wall.
The SBIR is ofcourse something thats unavoidable with such a loudspeaker, but the problem area with SBIR is in 100- 250 Hz , not in the midrange and treble area where its much more problematic.
 
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Tangband

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I'm not too sure about this? Pulling speakers out from the wall can actually make SBIR worse unless they are pulled out so far as to make it impractical in a real space. In a high fidelity system(subs, bass managed, eq), keeping speakers closer to the wall can lessen the effects of SBIR, and in wall eliminates the issue from the enclosure wall.

As far as early reflections, doesn't this include side wall, ceiling, and floor in a potentially beneficial way, whereas the reflection off the back wall is more harmful(SBIR)? You'd still get all those reflections from in walls speakers, other than the more harmful SBIR.

.6 meters will cause a cancellation at 143 Hz(not better sound)

Early reflections within about 2-3 ms sounds really bad in the midrange and tweeter area if you make the whole wall as a baffle. The sidewalls, ceiling and the floor are almost always more that 2 ms ( more than 70 cm ) away from the tweeter with freestanding loudspeakers, making the sound more clear.

The SBIR cancellation at 143 Hz ( witch is correct ) is much less disturbing when listening to music because its below the schröeder frequency in a normal room.

As I wrote before- you can have the cake and eat it at the same time- with damping material on the whole wall where you have the inwall speakers, minimizing early reflections in the midrange and tweeter area, and gain the benefit of nonexistant SBIR at the same time. Thats the way they do it in good studios. Live end, dead end.
For easy experiment, you can put a 1 inch thick felt-mat on the wall around each inwall loudspeaker, each about 1*1 meter .
85B6EAF1-6353-45AB-B91E-8309126501E6.jpeg
 
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abdo123

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You are absolutely right about that the whole wall becomes the baffle. And it will reflect sound at all frequencys, early reflections sounds really bad if its in the midrange and tweeter area.
Thats the main reason why conventional loudspeakers always gain clarity in midrange and tweeter area if they are moved from the wall.
The SBIR is ofcourse something thats unavoidable with such a loudspeaker, but the problem area with SBIR is in 100- 250 Hz , not in the midrange and treble area where its much more problematic.

I don’t understand how the baffle becomes a source for reflections when sound is coming outside (or moving away from) the baffle.
 

abdo123

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Howdy, you are the one who said "absence of SBIR", which is not true - so I wanted readership to be aware of that.
The other reflections are in effect, in wall installions remove the boundary/interference effect of the one wall they are mounted in.
As far as the "captain obvious", comment why be disrespectful? What is the point? Especially when you are not actually correct in your statements?

what’s the point of your mansplaining?

Everyone who knows what SBIR is understands that each wall/boundary produces it.
 

redshift

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what’s the point of your mansplaining?

Everyone who knows what SBIR is understands that each wall/boundary produces it.

It’s nothing wrong with sound bouncing around in the room? That’s what makes far-field listening more pleasant compared with, say, headphones or near-field monitors.

I think room reflections generally are quite unappreciated and combatted for no apparent reason.

Let the room resonate with the actuators.

1626095177985.jpeg


:cool:
 

nathan

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Early reflections within about 2-3 ms sounds really bad in the midrange and tweeter area if you make the whole wall as a baffle.

Based on the spinorama and other measurement data, it looks like a good waveguide can significantly reduce such issues and Harman, Genelec and a few others have achieved it in the past decade.

The thing they haven't solved is the visual bias of seeing a speaker in a wall and thinking it won't have air, openness and clarity in the treble, but their blind listening tests have at least shown us these are sighted biases and not measurable or audible problems.

Or at least I cannot find any measurements or double blinds tests that say otherwise, yet.
 

redshift

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Based on the spinorama and other measurement data, it looks like a good waveguide can significantly reduce such issues and Harman, Genelec and a few others have achieved it in the past decade.

The thing they haven't solved is the visual bias of seeing a speaker in a wall and thinking it won't have air, openness and clarity in the treble, but their blind listening tests have at least shown us these are sighted biases and not measurable or audible problems.

Or at least I cannot find any measurements or double blinds tests that say otherwise, yet.

The speaker could be designed for taking advantage of early reflections, such as Larsen speakers and oldie Sonabs/Carlssons.

I think this field is ripe for further exploration with excellent measurement tools and competent algorithms.
 

ROOSKIE

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what’s the point of your mansplaining?

Everyone who knows what SBIR is understands that each wall/boundary produces it.
Friend throw out all the derogatory and distracting zingers you want, I am not mansplaining, additionally I highly doubt that every reader here understands SBIR just because they have heard of it or know what it "is".
This is a fairly technical topic and ought to be fairly explained. In any case your original statement was simply not correct and may have confused some people about false advantages of in wall designs. Move on and if need be use the ignore member option like I am about to.
 
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Chromatischism

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It’s nothing wrong with sound bouncing around in the room? That’s what makes far-field listening more pleasant compared with, say, headphones or near-field monitors.

I think room reflections generally are quite unappreciated and combatted for no apparent reason.

Let the room resonate with the actuators.

View attachment 140676

:cool:
I tend to like the clarity of my IEM's, and my neutral desktop setup and midfield theater setup. I tend to notice a reduction in satisfaction when the room gets echoey.
 

redshift

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I tend to like the clarity of my IEM's, and my neutral desktop setup and midfield theater setup. I tend to notice a reduction in satisfaction when the room gets echoey.

I agree. It isn’t easy to beat good cans and near field monitors if “raw” fidelity is a priority.

I tend to prefer the sound from far fielders despite the additional “processing” from the room.

It is a miracle that the auditory system can resolve anything at all out of the chaos that is the room and speakers interacting.
 

nathan

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I find it really depends on the speakers. Those with neutral off axis response that mirrors the on axis response tend to do well in a room -- and a few decades of research match that anecdotal impression.

Cans have the advantage similar to near field placement or a very damped room whereby off axis response is killed off so if the on axis response is good, you can get something that sounds very nice.
 
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redshift

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I find it really depends on the speakers. Those with neutral off axis response that mirrors the on axis response tend to do well in a room -- and a few decades of research match that anecdotal impression.

Cans have the advantage similar to hear field placement or a very damped room whereby off axis response is killed off so if the on axis response is good, you can get something that sounds very nice.

Right.

Rooms “ruin” competent far fielders in a good way if you’re bent that way. I know I am.
 

nathan

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Well since most of what we hear is the room (I don't just mean below the transition, where it's all the room in a sense) "ruins" is a funny word and I'm glad you put quotes around it. I mean, in a sense, speakers/headphones can do nothing but alter the signal -- some just do it less than others and or in less damaging ways! ;)
 

Trouble Maker

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Thanks for doing this and taking the time to post, it's near and dear to my heart. I've been wanting to do all in walls for a while but just haven't made the jump. Or maybe I should say I haven't been convinced enough that the trade-offs are too great e.g. low performance for cost, more than I'm willing to lose to gain in walls. My latest idea was these Revel in-walls, and the more expensive ones. So to see the less expensive ones perform pretty well gives me some hope. I think I would still do W89x across the front. But being able to do less expensive ones for sides and also 4x heights I would like to do would have a significant effect on overall cost. Going 'down' to the x263 from the x563 across 6 speakers would save around $900 (retail).
 

abdo123

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Thanks for doing this and taking the time to post, it's near and dear to my heart. I've been wanting to do all in walls for a while but just haven't made the jump. Or maybe I should say I haven't been convinced enough that the trade-offs are too great e.g. low performance for cost, more than I'm willing to lose to gain in walls. My latest idea was these Revel in-walls, and the more expensive ones. So to see the less expensive ones perform pretty well gives me some hope. I think I would still do W89x across the front. But being able to do less expensive ones for sides and also 4x heights I would like to do would have a significant effect on overall cost. Going 'down' to the x263 from the x563 across 6 speakers would save around $900 (retail).

The Revel in wall speakers are really impressive, when I saw how straight forward they were I really felt jealous because in Europe walls are either concrete or bricks, we don't have the typical paper US walls where you can saw, drill and do whatever.
 

redshift

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Well since most of what we hear is the room (I don't just mean below the transition, where it's all the room in a sense) "ruins" is a funny word and I'm glad you put quotes around it. I mean, in a sense, speakers/headphones can do nothing but alter the signal -- some just do it less than others and or in less damaging ways! ;)

Yes it is intended tongue in cheek with a dash of comedy and drama. It’s all fun and silliness with audio (and forums)

I think it’s called a hobby for good reasons. BTW; an engineer is just a person that gets paid for the fun and games of audio. Luckily no manager will observe me spilling the beans.
 

redshift

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Thanks for doing this and taking the time to post, it's near and dear to my heart. I've been wanting to do all in walls for a while but just haven't made the jump. Or maybe I should say I haven't been convinced enough that the trade-offs are too great e.g. low performance for cost, more than I'm willing to lose to gain in walls. My latest idea was these Revel in-walls, and the more expensive ones. So to see the less expensive ones perform pretty well gives me some hope. I think I would still do W89x across the front. But being able to do less expensive ones for sides and also 4x heights I would like to do would have a significant effect on overall cost. Going 'down' to the x263 from the x563 across 6 speakers would save around $900 (retail).

You could try it out with some second hand Larsen’s or oldie renovated Sonab/Carlsson speakers. However, I’m not sure those are for everybody used to sweet spot listening.

They integrate quite well in the living room as they are supposed to sit flush with the back against the wall.

I’m currently sporting a pair of Carlsson OA61’s which is based on an upgraded OA51, a design from the early 80’s.

Below is a site that details upgrades to old Carlssons with better electronics and actuators. Bring your (google) translator with you.

http://www.carlssonkult.se/OA51.aspx

They seem to measure quite well and I think they sound good. Not sure if they are worth the money as newly produced OA61’s, though.
 

Thomas_A

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Early reflections within about 2-3 ms sounds really bad in the midrange and tweeter area if you make the whole wall as a baffle. The sidewalls, ceiling and the floor are almost always more that 2 ms ( more than 70 cm ) away from the tweeter with freestanding loudspeakers, making the sound more clear.

The SBIR cancellation at 143 Hz ( witch is correct ) is much less disturbing when listening to music because its below the schröeder frequency in a normal room.

As I wrote before- you can have the cake and eat it at the same time- with damping material on the whole wall where you have the inwall speakers, minimizing early reflections in the midrange and tweeter area, and gain the benefit of nonexistant SBIR at the same time. Thats the way they do it in good studios. Live end, dead end.
For easy experiment, you can put a 1 inch thick felt-mat on the wall around each inwall loudspeaker, each about 1*1 meter .
View attachment 140623

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.
 
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redshift

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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.

More technical detail about the design principles of Carlsson speakers for those who are curious (in English this time… w007!! :eek:)

http://user.faktiskt.io/schmutziger/OA51 FAQ/pdf/carlsson_ortho_design_principles.pdf

:)
 
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AudioJester

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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?
 
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