Room Treatment to get Soundstage, Spaciousness & Imaging?

[Cinema40]

Hello all,
I'm currently running a 5.4.2 setup (upgrading to 5.4.4) with Focal Aria 926s, Marantz Cinema 40, and quad subs optimized via Dirac ART. The bass response is flat and controlled, but I'm missing the soundstage depth, spaciousness, and instrument placement that reviewers describe. The phantom center image is solid, but instruments don't feel positioned around the room—the sound clearly comes from the speakers rather than creating an immersive sound bubble.

My room is 16.33' L × 14' W × 10.5' H with the MLP 3.5' from the back wall and centered width-wise. The speakers are 18" from the side walls and 2–4" from the front wall (core issue for my problems I believe). My RT60 measurement without DSP sits between 0.3–0.35s across 100 Hz–10 kHz, which is a good baseline. The quad subs and Dirac ART handle the bass modes effectively.

The main constraint is that I can't move the speakers forward due to door placement, but the renovation gives me freedom for acoustic treatments. I've attached room renderings (of the current setup) and measurements taken with mains only and no room correction (curtains both open and closed). I'm looking for advice on targeted acoustic treatment to maximise the 2-channel listening experience within these constraints.

 

[Cinema40]

I am just adding the response I get with Dirac ART enabled and limiting the correction to 300hz below. The measurement given below is an average of the center three seats of the room.

 

[Beave]

I'm guessing that's an AI rendering of the room and not a real pic? Otherwise those Focals have some funky drivers!

What center speaker are you using?

Is your complaint with 2 channel stereo music?

To me, your L & R might be too far apart and too close to the side walls. Maybe put the subs in the corners and move the speakers in their place (roughly).

 

[Keith_W]

Take a look at my signature. Follow the link, and it will take you to my Google Drive folder. In it, you will find a few documents. You want these two:

1. Acoustic Targets for Listening Rooms, by Nyal Mellor.
2. REW Full eBook, written by myself.

The first document tells you what to aim for. The second tells you how to take measurements to check if your room complies with the acoustic targets.

There is also a powerpoint presentation in there called "MAC Talk Treble" which is a talk I gave at the local audio club about measurement targets for upper frequencies, along with a discussion about room treatment.

 

[Cinema40]

I'm guessing that's an AI rendering of the room and not a real pic? Otherwise those Focals have some funky drivers!

What center speaker are you using?

Is your complaint with 2 channel stereo music?

To me, your L & R might be too far apart and too close to the side walls. Maybe put the subs in the corners and move the speakers in their place (roughly).

Yes I chose to share an AI render since the room is currently under going some work and this showed the constraints quite clearly.

Center speaker is a Focal CC900. Complaint is with 2 channel music only.

The wall is 168 inches wide and the screen is 108 inches wide. 30 inches of space on both sides. I have placed the subs under the projector screen at 1/4 and 3/4 points of the front wall and rear wall as it gives me the most even bass response.

 

[SigbergAudio]

I'd contradict the previous poster, you want your speakers as wide as possible. Have you tried moving the listening position forwards, so closer to the speakers, so they're relatively speaking even wider?

To some extent it may be the speakers as well, but I don't know them personally. The decay time of your room is already low and relatively even, so I'm not convinced further treatment will improve this.

Your untreated response doesn't look very good (assuming you're measuring correctly).

I'd also say your subwoofers are at least 5dB too hot (loud), especially for music. Maybe even 7-8dB.

 

[Cinema40]

I'd contradict the previous poster, you want your speakers as wide as possible. Have you tried moving the listening position forwards, so closer to the speakers, so they're relatively speaking even wider?

To some extent it may be the speakers as well, but I don't know them personally. The decay time of your room is already low and relatively even, so I'm not convinced further treatment will improve this.

Your untreated response doesn't look very good (assuming you're measuring correctly).

I'd also say your subwoofers are at least 5dB too hot (loud), especially for music. Maybe even 7-8dB.

Thanks for your response.

My listening position can be moved backwards and not forwards into the room due to some space constraints. I would hope that the speakers have good soundstage as I only bought them after reading numerous reviews from owners on ASR only.

I have attached better measurements of the Untreated room below. The MIC position may have been causing an issue with the tweeter's response.

 

[SigbergAudio]

Thanks for your response.

My listening position can be moved backwards and not forwards into the room due to some space constraints. I would hope that the speakers have good soundstage as I only bought them after reading numerous reviews from owners on ASR only.

I have attached better measurements of the Untreated room below. The MIC position may have been causing an issue with the tweeter's response.

View attachment 547867View attachment 547868

Thank you. The measurements don't directly show us how well the system will perform with regards to soundstage and imaging I'm afraid.

Have you heard systems that do this well, so that you know what you are trying to achieve? And do you know that the recordings you are testing have good imaging/soundstage?

You said you feel like the sound comes from the speakers, that typically shouldn't be the case for almost any source material assuming things are set up correctly. Have you tried disabling the room correction alltogether? Does the imaging/soundstage get better or worse?

 

[ppataki]

In my experience, you will not get real soundstage depth and holographic presentation unless you pull your front speakers forward from the front wall by at least 150cm
I know you cannot do this due to room constraints in the long run but just give it a try temporarily to hear the (huge) difference

 

[SigbergAudio]

In my experience, you will not get real soundstage depth and holographic presentation unless you pull your front speakers forward from the front wall by at least 150cm
I know you cannot do this due to room constraints in the long run but just give it a try temporarily to hear the (huge) difference

This isn't necessarily true, and he should at least still get soundstage width + proper imaging.

 

[ppataki]

Width, yes but no depth

 

[Cinema40]

Thank you. The measurements don't directly show us how well the system will perform with regards to soundstage and imaging I'm afraid.

Have you heard systems that do this well, so that you know what you are trying to achieve? And do you know that the recordings you are testing have good imaging/soundstage?

You said you feel like the sound comes from the speakers, that typically shouldn't be the case for almost any source material assuming things are set up correctly. Have you tried disabling the room correction alltogether? Does the imaging/soundstage get better or worse?

If i may explain what I'm hearing better and how I'm hearing it -
Source: Apple Music on Apple TV (Lossless Audio)
Artists typically listened to: Fleetwood Mac, Pink Floyd, Dire Straits, The Strokes and Daft Punk.
Imaging and Soundstage: Imaging improves with Room Correction, No changes in soundstage.
Speaker Toe In: Assuming that Speaker pointed at MLP means that its on axis, speakers are toed out by 5-10degrees.

In most recordings (if visualised) the singer is in the dead center of the room and the phantom centre image is solid. There is instrument separation and I can tell when an instrument moves from the left speaker to the right but there is no depth or music coming from beyond the speaker boundaries. I have made an illustration to better explain the situation.
Areas in Green is where instruments and singers can be pin pointed to. Areas in orange have a hazy placement of instruments and singers. I get no sensation of sound from anywhere in the areas in red.

 

[SigbergAudio]

Width, yes but no depth

Since we make speakers that are explicitly designed to be placed close to the wall, while still providing a 3D soundstage, I will agree to disagree. May not be possible with all speakers, but definitely possible.

 

[SigbergAudio]

If i may explain what I'm hearing better and how I'm hearing it -
Source: Apple Music on Apple TV (Lossless Audio)
Artists typically listened to: Fleetwood Mac, Pink Floyd, Dire Straits, The Strokes and Daft Punk.
Imaging and Soundstage: Imaging improves with Room Correction, No changes in soundstage.
Speaker Toe In: Assuming that Speaker pointed at MLP means that its on axis, speakers are toed out by 5-10degrees.

In most recordings (if visualised) the singer is in the dead center of the room and the phantom centre image is solid. There is instrument separation and I can tell when an instrument moves from the left speaker to the right but there is no depth or music coming from beyond the speaker boundaries. I have made an illustration to better explain the situation.
Areas in Green is where instruments and singers can be pin pointed to. Areas in orange have a hazy placement of instruments and singers. I get no sensation of sound from anywhere in the areas in red.

View attachment 547891View attachment 547892

That is a good explanation of your experience. Do you have treatments on the side walls?

If you test this track, can you share how you experience the panning sounds in the beginning?

 

[Cinema40]

That is a good explanation of your experience. Do you have treatments on the side walls?

If you test this track, can you share how you experience the panning sounds in the beginning?

The left wall has a large glass window covered by a very thick curtain. The right side wall has 6 2ft x 4ft x 2 inch thick rockwool panels.

I will listen to the track and report back with the findings soon!

 

[SigbergAudio]

The left wall has a large glass window covered by a very thick curtain. The right side wall has 6 2ft x 4ft x 2 inch thick rockwool panels.

I will listen to the track and report back with the findings soon!

When you do, if possible,

1) Test with your current configuration, and
2) if possible also with the curtains removed and the rockwool panels temporarily moved elsewhere (for instance the front or back wall).

 

[OCA]

There appears to be a bug where ART drops support speakers during stereo playback, running subwoofers solo. This compromises the front-stage bass response and destabilizes soundstage imaging. The best fix is building a dedicated 2.1 ART calibration preset for music listening. Also, on the Marantz Cinema 40, leave the "2.0 stereo" setting on "Auto" - alternative settings produced unexpected results in my Audyssey measurements.

Regarding curtain limits: consider running ART up to 1 kHz. While the 200 Hz–400 Hz band suffers from filter transition issues (MIMO to SISO), ART’s linear phase processing remains effective up to 1 kHz (see the post ART phase graph below). Implementing a steep 300 Hz curtain with its sharp fade out will create even worse artifacts right in the fundamental frequency zone critical for precise instrument localization.

And forget about room treatment. Majority of setups will only suffer from it.

 

[SigbergAudio]

And forget about room treatment. Majority of setups will only suffer from it.

That is a very interesting statement. Care to elaborate?

 

[Cinema40]

There appears to be a bug where ART drops support speakers during stereo playback, running subwoofers solo. This compromises the front-stage bass response and destabilizes soundstage imaging. The best fix is building a dedicated 2.1 ART calibration preset for music listening. Also, on the Marantz Cinema 40, leave the "2.0 stereo" setting on "Auto"—alternative settings produced non-linear/unexpected results in my Audyssey measurements.

Regarding curtain limits: consider running ART up to 1 kHz. While the 200 Hz–400 Hz band suffers from filter transition issues (MIMO to SISO), ART’s linear phase processing remains effective up to 1 kHz (see the post ART phase graph below). Implementing a steep 300 Hz curtain with its sharp fade out will create even worse artifacts right in the fundamental frequency zone critical for precise instrument localization.

And forget about room treatment. Majority of setups will only suffer from it.

Hello OCA,
Thanks for your response. I have setup dirac ART in a way that no other speaker other than the 4 subs support the front speakers. If i added my surround and height speakers, I felt that it collapsed all imaging and it just sounded very two dimensional. The AVR is always on Auto Mode when in use, I only use the pure direct mode to make measurements as it allows me to use the distance and level trim adjustments from Dirac.

I am reading up on the book @Keith_W just shared with me and will soon understand what phase graph you've shared here

 

[whazzup]

Thanks for your response.

My listening position can be moved backwards and not forwards into the room due to some space constraints. I would hope that the speakers have good soundstage as I only bought them after reading numerous reviews from owners on ASR only.

I have attached better measurements of the Untreated room below. The MIC position may have been causing an issue with the tweeter's response.

View attachment 547867View attachment 547868

Just curious about the dip close to 200hz. Is that a sub integration issue?