[Desertpilot]

I'm starting this thread to gather Spatial dipole owners' thoughts on how they are using room treatments (acoustic absorption and/or diffusion panels).  Are you using room treatments at all?  Do you hear a difference?  Are you taking measurements and adjusting room treatments accordingly?  Clayton has said in a few of his interviews that the beauty of dipole speakers is reducing or even eliminating "room interaction" with his speakers.  The design cancels side wall and ceiling interaction.  If so, why use room treatments at all?  Of course, with dipoles, distance from front or side walls is critical.  But, absorption and/or diffusion?  Maybe not so much.

I've watched way too many videos discussing "proper" room treatments as the path to audio nirvana.  Alternatively, many experts oppose room treatments.  What's an audiophile to do?

Paul McGowan of PS Audio agrees that diffusion on the front wall may help.  But, he personally prefers to leave the front wall alone.  https://www.youtube.com/watch?v=5raaq5Gqalc

The Audioholics team recently tackled the topic, "What is the ideal listening room".  Matt argues that minimal treatment might just be perfectly fine.  Carpet, curtains, sofas, etc. might get the job done.  https://www.youtube.com/watch?v=urfvhXcb43w&t=1s.  They recently ran a multi part series on room treatments.  Good information but way overkill for most consumers.

I have GIK absorption/diffusors on my front wall.  I thought it was important.  But, I recently took them down as I am having work done in my listening room.  You know what?  I can't hear much difference.  So what is your experience?  Do dipole speakers need acoustic treatment panels?

Marcus

[ric]

I really like the Acoustic Fields videos on YT--he's a no nonsense guy with straight talk about what to do, what not to do. One of their bass traps use activated charcoal and weigh 200lbs!
       I have done very minor experimentation with bass using 2'x4'x6" rock wool type insulation and it helps a little with boomy bass response, but I found that if I use it in the corners it messes with the soundfield in a negative way, but overall having them tends to smooth out the sound.
       I still am a big fan of DIY Shakti Hallographs which I toe in or out (or straight) depending on the recording. if you are ever listening to a string quartet or piano concerto and the ambience/soundstage doesn't sound right, for me, these do the trick (usually).
Since you are new to your speakers I would suggest slowing down a bit and get to know them for weeks or a few months. Adjust positioning as needed. I wouldn't jump to room treatment unless you are hearing something (usually bass) really wrong, and have looked at amp, cables etc, in the process.

[abomwell]

I don't have my X5's yet but I've owned three sets of dipoles for a number of years. My understanding is that the speakers need to be out from the front wall far enough for the reflected back wave to be delayed at least 6ms in order for the ear/ brain to distinguish the direct sound from the reflected sound. That translates to at least 3' away from the front wall.

There is a school of thought, and I know Clayton strongly agrees with this, that the reflections need to be a full spectrum of the direct sound and have the same sonic signature (frequency response). This allows the brain to perceptually ignore the reflections.  Otherwise the reflections become distractions
resulting in a number of perceptual issues and listener fatigue.
So the bottom line is pull the speakers out from the front wall at least 3' and leave the front wall behind the speakers alone or diffuse it, don't use absorption.

Al

[FlowerButcher]

This might help someone out go to you tube video.
https://www.youtube.com/watch?v=Su41Ivt7VbA
and go to the 1hr 57 min mark.

[Desertpilot]

Thanks Ric and Al.  All good advice.  Yes, I've watched every Acoustic Fields videos.  Lots of great information.  Spoke with him a couple years ago.  Can't afford his room treatments.

Yesterday, as I said, I pulled out my 3 front wall GIK diffusor panels out to allow some electrical work (not audio related) to be done.  Later in the day, my wife asked me where they were.  I always thought she didn't like having them.  Instead, she said they need to go back because they cut the sound down in the Master Bedroom (backside of the front wall).  Married 20 years and I still learn new stuff about us.

Over on the REW forum at AV Nirvana, a couple experts answered my question about dipole speakers and REW.  They said REW works just fine for dipoles.  Speaker position is the first critical step.  Speaker distance from the front wall is the most critical (they referenced the CARDAS website, http://www.cardas.com/room_setup_calculators.php).  They have a calculator for both box speakers and dipole speakers.  Cardas recommends a little over 7 feet from the front wall (in my situation).  I'm at 4.5 feet which is about as far as I can go.

Once the electrical work is done, I'll put the diffusor panels back and reset the speakers.  I may delay REW, as Ric suggested.  I'm getting a third X3 for center channel duties and might as well wait until it arrives (Clayton said about a month).  That will give me plenty of time to get used to my current set up.

Marcus

[abomwell]

Here is link to Linkwitz's suggested starting points for both dipole and monopoles speakers. See section D towards to bottom.
https://www.linkwitzlab.com/rooms.htm

Al

[abomwell]

One question I have regards doors in the room. I get smoother measured bass leaving the 5' french door, located in the right rear corner of my room, open when using monopole speakers. The door acts like a bass trap. But dipole woofers pressurize the room differently than do monopoles. Has anyone
heard, or measured, a difference in bass response with the door(s) open vs. closed?

Al

[Desertpilot]

I positioned my GIK 6A 2D-a absorber/diffusor panels behind my X3s.  I raised the panels up off the floor 6 inches so they are directly behind all three drivers.  I think they improve the sound, especially the AMT driver.  I had a couple GIK bass traps so I put them up front as well (between the diffusor panels).  Not sure yet if that's the best use of them.  Speakers are 5 feet from front wall so plenty of space to let reflections diminish.  I have similar GIK absorber/diffusor panels on my rear wall.  But, the rear wall is 30 feet from the front wall.  I suppose they help but 30 feet is a long distance.

I don't think there is anything more I can do.  I have thick blackout curtains all along the left sidewall to cover windows.  I'm pretty sure they attenuate reflections a sufficient amount.  Carpet and pad on the floor.  Plus several thick fabric covered recliners about 10 feet from the speakers.  No echo that I can detect.  The room is not dead either.  Ceiling is vaulted 11 to 14 feet.  I've not treated it at all.  For such a gigantic great room, I am completely out of space for any more room treatments.

I need to run REW.  But, listening is the true test.  From my point of view, I feel I am hearing everything.  I'll run REW just to prove to myself that I am indeed hearing every note.  The X3s are motivating me to get the best sound possible from them.

Marcus

[abomwell]

Great update, Marcus. Many audiophiles would kill to have a room as yours! Looking forward to seeing your REW results.

Al

[Desertpilot]

Great update, Marcus. Many audiophiles would kill to have a room as yours! Looking forward to seeing your REW results.

Al

Thanks Al.  I thought I would post a couple photos.  The old center channel speaker is disconnected.  I am only playing stereo (2.0) versions of my music.


View from the MLP.  10 feet to speakers.  15 feet to front wall.  I added the GIK bass traps because they were not being used elsewhere.




Side view.  I had a couple extra GIK diffusors so I put them to the sides.




Marcus

[abomwell]

Looks good, Marcus. Do you listen to 2.0 with the screen up?

Al

[Desertpilot]

Looks good, Marcus. Do you listen to 2.0 with the screen up?

Al

The screen is fixed to the wall.  I've thought a million times about hanging a curtain to close over the screen.  But, I think I am at my limit with modifications, especially the WAF.  The screen is above the speakers so I don't think there are a lot of reflections.  Time to become content, drink some delicious Cabernet and enjoy the system.

Marcus

[abomwell]

I always thought my system sounded better after a Manhattan
(or two)

Al

[reillyzing]

How does an opening on one side of the room (as seen in the photo above) effect the performance, if at all, of Spatial Audio speakers? I've been considering the X series and Sapphire.

[JTF]

I've found treatments, specifically bass traps essential. I had huge dips (measured with REW) at 40-50hz and between 100-200hz, due to the room. The bass wasn't living up to expectations initially. You don't need to spend a lot, I built mine for a few hundred. After gaining experience with room treatment, I'd rank it right up there, right after the speakers in order of importance to the sound of the whole system.

[Desertpilot]

How does an opening on one side of the room (as seen in the photo above) effect the performance, if at all, of Spatial Audio speakers? I've been considering the X series and Sapphire.

Asymmetrical shaped rooms can create problems.  I installed a right side wall with acoustic panels in an effort to create symmetry.    It not only looked bad it didn't do anything to improve sound.  I just did not notice any difference.  So, I abandoned the effort.  Maybe it is the side cancelation of the open baffle design.  In my room, the sound is glorious even with the right side open to the great room.  I feel I have a cohesive and well defined soundstage.

Marcus

[TomS]

The right side of my room with X5's is completely open to an entry/hallway/kitchen. I do have quite a few room treatments, but haven't really found the asymmetry to be a problem for the Spatials.

[Desertpilot]

The right side of my room with X5's is completely open to an entry/hallway/kitchen. I do have quite a few room treatments, but haven't really found the asymmetry to be a problem for the Spatials.

Thank you Tom.  It's nice to know I am not alone in my assessment of the Spatials and an open floor plan.  I agree about room treatments.  I think it is time for me to run REW and find out if my hearing is correct.  More later.

Marcus

[abomwell]

Marcus, depending on what REW shows, and if you have a way of using a parametric EQ filter you might be interested in trying a psycho-acoustical  dip of -4dB centered at 3kHz with a Q of .75.
I use this for many orchestral and choral recordings. It really helps most recordings sound more natural. See below from the Linkwitz website for explanation:

Al

"Around 3 kHz our hearing is less sensitive to diffuse fields. Recording microphones, though, are usually flat in frequency response even under diffuse field conditions. When such recordings are played back over loudspeakers, there is more energy in the 3 kHz region than we would have perceived if present at the recording venue and a degree of unnaturalness is introduced.
This applies primarily to recordings of large orchestral pieces in concert halls where the microphones are much closer to the instruments than any listener. At most listening positions in the hall the sound field has strong diffuse components.
I use a dip of 4 dB (x1.gif, 2760NF) to equalize for this. The circuit consists of R, C and L in series, forming a frequency dependent ladder attenuator in conjunction with the 5.11k ohm source resistor. You may choose to make the notch filter selectable with a switch for different types of recordings.

I have found through my own head-related recordings of symphonic music that the dip adds greater realism, especially to large chorus and to soprano voice and allows for higher playback levels.   

[Desertpilot]

Marcus, depending on what REW shows, and if you have a way of using a parametric EQ filter you might be interested in trying a psycho-acoustical  dip of -4dB centered at 3kHz with a Q of .75.
I use this for many orchestral and choral recordings. It really helps most recordings sound more natural. See below from the Linkwitz website for explanation:

Al

"Around 3 kHz our hearing is less sensitive to diffuse fields. Recording microphones, though, are usually flat in frequency response even under diffuse field conditions. When such recordings are played back over loudspeakers, there is more energy in the 3 kHz region than we would have perceived if present at the recording venue and a degree of unnaturalness is introduced.
This applies primarily to recordings of large orchestral pieces in concert halls where the microphones are much closer to the instruments than any listener. At most listening positions in the hall the sound field has strong diffuse components.
I use a dip of 4 dB (x1.gif, 2760NF) to equalize for this. The circuit consists of R, C and L in series, forming a frequency dependent ladder attenuator in conjunction with the 5.11k ohm source resistor. You may choose to make the notch filter selectable with a switch for different types of recordings.

I have found through my own head-related recordings of symphonic music that the dip adds greater realism, especially to large chorus and to soprano voice and allows for higher playback levels.

Thanks Al.  JRiver Media Center does offer a parametric equalizer.  I can select a frequency and add or subtract Db.  As an aside, I could also select "Linkwitz Transform" and/or "Linkwitz-Riley".  I don't know what those selections mean but thought I would mention it.

As an aside, since I am using a DAC, all pre/pro settings are ignored and the analog signal is passed directly to my amplifier.  I asked about speaker distance/timing and was advised to set the distance in JRiver.  It is there and I am using it.  That leads me to believe the parametric equalizer must also work.  I don't know how it does it to the digital file but somehow it does.  It's all magic to me.  I know we want to minimize alterations to the file.  But, heck, it's worth a try.

Marcus