Pros and Cons of Sealed Listening Rooms
- Thread starter Ron Resnick
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PeterA: Maybe I focus on vocals because I am highly "evolved."
Good one Ron
, indeed you are. I'm glad to be reading this first thing in the morning. I love vocals and am increasingly enjoying choral music. Favorites include Johnny Hartman, Shirley Horn, Carla White, Ella Fitzgerald and Louis Armstrong, Peter Schreiber, Fischer-Dieskau, Leonie Rysanek, Anne Wilson, Ian Gillan. So many...and then the voices of my two daughters waking up their father years ago.Voices fall in a very sensitive range for us, and I think that is why I like the cello and French horn so much.
You gotta be kidding me (it's spectacular), this is your system?
https://systems.audiogon.com/systems/729
Looks like from the link you have plenty of room treatments.
So it's just the glass, and it's behind your head?
5 of the Best Sound Proof Curtains You Can Buy
Soundproof Curtains, Acoustic Treatment & Myths You Need to Know
https://apathappears.org/soundproof-curtains-acoustic-treatment-myths-you-need-to-know/
https://systems.audiogon.com/systems/729
All I can suggest is moving your speakers away from the corners and out from the front wall because the room boundaries are going to reinforce bass too much - in my opinion. And move them speakers closer together, verify sweetspot by providing a floor plan layout drawn on grid paper with each square equally a foot.
I also like some absorption mixed with diffusion in between the speakers at ear level, cable hung from ceiling holding thinner panel covered with art would do the trick - would hate to affix to that wood. This is to reinforce your phantom center stage, which may be nonexistent at this point.
Are those sliding wood panels hiding a TV? I've see that done before.
Again, your room is all so beautiful, but also breaks far too many acoustic rules.
EDIT:
https://systems.audiogon.com/systems/729
The Swarm didn't fix the main speakers poor location?
Are they hung from the ceiling in a 1/4 room placement pattern?
https://www.gikacoustics.com/room-setup-speaker-placement-201-part-two-subwoofers/
http://www.linkwitzlab.com/rooms.htm
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After reading this thread, I have done some listening experiments. I have a small room, 15' X 16' X 7.5'. Speakers are on the slightly longer wall, with tweeters about 5' out into the room because of a protruding fireplace. Tweeters are 51" in from each side wall, and speakers are pointing straight ahead, zero toe-in. I have wood louvered blinds over the windows and have recently removed all acoustic room treatmens except for a 2' X 2' absorption panel 12" on the wall behind the listening seat. Construction is very heavy plaster/lathe over post and beam construction in a house built in the 1790s.
I listened again with two 12" X 48" ASC absorptive panels at the two first reflection points, determined with a mirror. The panels increase sense of focus very slightly, but it comes at the expense of liveliness and energy in the room. Going back and forth a few times, I hear and appreciate the tradeoffs and now prefer slightly, the more energized acoustic without the panels in the room. The music simply comes alive more. I can live with slightly less definition and focus. If not concentrating and switching back and forth a few times while listening to a variety of music, I probably would not even notice the difference. The room certainly looks better without the panels.
The other experiment I did was listening with the door open. The door is located in the rear right corner when facing the speakers. Again, the sound is very similar both ways, but the room is slightly more energized with the door closed and the music is less loud in the rest of the small house which is better for my wife in the evenings.
The room is symmetrical along the listening axis and openings are shut. However, the room certainly leaks because it is so old. It is not what I would describe as "sealed", like the Magico listening room I heard during a tour of those facilities. The door does not fit tightly, there are gaps in the floor. There is the open fireplace which has a chimney top damper.
Given the small dimensions and reflections and speaker position, there are a lot of reflections, but the music sounds very natural to me, and it is very clean, clear and dynamic. Images can be localized quite easily, and there is lots of layering and distinct recording venue information that comes across. These last few attributes were difficult to achieve or realize because of the reflective nature of the space without all of the former room treatments. It took a long time to find the proper speaker locations, much more so than when the speakers were toed-in.
I appreciate that we are discussing some general principles about room acoustics, treatments, and dimensions. However, I have found that there are instances where rooms can seem to break the conventional rules. Mine might be one of them. I also think some of this depends on one's preferences. I have traded some definition and what I think of as "hifi" attributes for a more organic, energized, or natural sound.
I think I hear slightly less direct sound, and slightly more reflected sound, than some others might prefer. It is certainly not a sound for everyone as some visitors have remarked, but I thought I would share the specifics of my room to give hope to those with small multi-purpose rooms with low ceilings in which lots of acoustic treatments may not be wanted for aesthetic reasons. I can say that I have never felt more engaged by the music in this challenged room.
Before:
After:
I listened again with two 12" X 48" ASC absorptive panels at the two first reflection points, determined with a mirror. The panels increase sense of focus very slightly, but it comes at the expense of liveliness and energy in the room. Going back and forth a few times, I hear and appreciate the tradeoffs and now prefer slightly, the more energized acoustic without the panels in the room. The music simply comes alive more. I can live with slightly less definition and focus. If not concentrating and switching back and forth a few times while listening to a variety of music, I probably would not even notice the difference. The room certainly looks better without the panels.
The other experiment I did was listening with the door open. The door is located in the rear right corner when facing the speakers. Again, the sound is very similar both ways, but the room is slightly more energized with the door closed and the music is less loud in the rest of the small house which is better for my wife in the evenings.
The room is symmetrical along the listening axis and openings are shut. However, the room certainly leaks because it is so old. It is not what I would describe as "sealed", like the Magico listening room I heard during a tour of those facilities. The door does not fit tightly, there are gaps in the floor. There is the open fireplace which has a chimney top damper.
Given the small dimensions and reflections and speaker position, there are a lot of reflections, but the music sounds very natural to me, and it is very clean, clear and dynamic. Images can be localized quite easily, and there is lots of layering and distinct recording venue information that comes across. These last few attributes were difficult to achieve or realize because of the reflective nature of the space without all of the former room treatments. It took a long time to find the proper speaker locations, much more so than when the speakers were toed-in.
I appreciate that we are discussing some general principles about room acoustics, treatments, and dimensions. However, I have found that there are instances where rooms can seem to break the conventional rules. Mine might be one of them. I also think some of this depends on one's preferences. I have traded some definition and what I think of as "hifi" attributes for a more organic, energized, or natural sound.
I think I hear slightly less direct sound, and slightly more reflected sound, than some others might prefer. It is certainly not a sound for everyone as some visitors have remarked, but I thought I would share the specifics of my room to give hope to those with small multi-purpose rooms with low ceilings in which lots of acoustic treatments may not be wanted for aesthetic reasons. I can say that I have never felt more engaged by the music in this challenged room.
Before:
After:
Ceiling height is typically the shortest dimension in a listening room, profoundly impacting the distribution and density of (undesirable) nodal modes in the bass frequencies. Room treatment should therefore address (among other things) alleviation of bass buildup; maximum bass pressure typically develops at closest boundaries as well as between parallel surfaces - on the front wall (behind the speakers), as well as on the floor/ceiling (directly above the bass drivers/ports). In my ten-foot ceiling height listening room, I have mounted on a grid of steel beam girders, twenty 30” x 30” acoustic modules collectively weighing ~1,000 kgs, an assortment of diaphragmatic bass absorbers tuned to 30-50Hz (five in a row placed horizontally, directly above the speakers), 50-200Hz (in the next row, closer to the listening area) and quadratic diffusers (two rows of five, placed around the first ceiling reflection point, halfway between the speakers and the listening position).
On the subject of room nodes (relative to ceiling height), this video from Acoustic Fields explains it well:
On the subject of room nodes (relative to ceiling height), this video from Acoustic Fields explains it well:
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Yes, that's my system. Thank you for the compliments.
What you don't see there is:
1. a concrete 8' ceiling that goes half way to the listening position and then opens to a 16' ceiling.
2. the left wall is floor-to-ceiling windows.
3. there is no right wall as the room opens to a kitchen
4. the wall behind the listening position is concrete.
The Swarn helped a lot. It's one of the best things I've ever purchased in the hobby.
Yes, the TV is behind a few sliding panels.
If I move the speakers out that block access to the living room -- it puts the right speaker in a sort of passage way between the kitchen and living room (see new photo). If I keep speakers along that wall they can only be a foot or two away from the red wall.
If I go to a near-field listening set-up I'm thinking of putting the speakers along the window wall. I think I could pull them 3' or 4' out from the windows.
1. Some speakers are less prone to room boundaries or intended to be wall mounted.
Have you considered horns or on the wall Martin Logan's?
2. Can you install a floating cloud to maintain the 8-foot ceiling?
3. Just read that toe-in and pulling or pushing one of the front speakers out of alignment with the other flanking speaker can somewhat make up for one sided room openings. Have you tried this?
You are in a pickle for any serious listening, have you considered an addition?
Either a new room for your stereo or new master bedroom and turn the master bedroom into dedicated listening room.
Advantage of the second option is the wife gets something out of it and is more likely to be on board.
1. Some speakers are less prone to room boundaries or intended to be wall mounted.
Have you considered horns or on the wall Martin Logan's?
2. Can you install a floating cloud to maintain the 8-foot ceiling?
3. Just read that toe-in and pulling or pushing one of the front speakers out of aliment with the other flanking speaker can somewhat make up for one sided room openings. Have you tried this?
You are in a pickle for any serious listening, have you considered an addition?
Either a new room for your stereo or new master bedroom and turn the master bedroom into dedicated listening room.
Advantage of the second option is the wife gets something out of it and is more likely to be on board.
I have not only considered horns, I have a pair on order! Odeon No. 33.
I live in a condo so I'm stuck with this room unless I move.
The human mind is your best weapon as it is highly adaptive and has the power to make you see what you want to see and hear what you want to hear.
The power of the illusionists over a crowd is one such example.
In other words, sometimes you get used to a situation because your subconscious mind compensates for it, which is why many of us like our own stereo systems and rooms verses what we experience in a new venue like a friends house or stereo shop.
At least that's my theory of the day.
Peter, I used the dimensions you gave and assumed your ear is about 2' from the rear wall to calculate the time delay of the first reflection from the side wall. It would arrive 5.2ms after the direct sound. You are just outside the 5ms window. It is when that first reflection is less than 5ms that it is really bad. I do know exactly what you are talking about as I have done the same experiments in different rooms/settings. If you can get away without the sidewall damping then the soundstage is bigger and more open sounding and I think most people would prefer this sound. (Toole's book points this out that people actually preferred an untreated sidewall) Your definitely right about the room looking better without the panels.
The following photo (taken with the iPhone Pro’s super-wide lens from the floor between the speakers, pointing up) shows my ceiling module array. The inside dimension of the white “box” (between the perimeter lights) is 14+ feet.
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Yes, I love going to magic shows and think the analogy is quite apt. Aren't we all trying to produce an illusion of the real thing with our systems and creating some kind of magic? I've heard some pretty convincing systems over the years. My subconscious mind must be compensating for all sorts of things.
Thank you sbnx. This is excellent information to have. My ears are actually about 15' from the back wall, so even a bit further from the speakers and first reflection points, but it is good to believe that those reflections are greater than 5ms. It makes sense based on what I am hearing. I nice confirmation or correlation between measurements and experience, assuming they are fairly accurate.
I suspect the surfaces and radiation patterns are also important. One think not yet discussed is whether or not it is better to have a live front of the room and dampened rear of the room, or visa versa, or more even, or something else. I notice that most halls have live fronts with wood floors and walls and that the audience area is much more absorptive with fabric seats and audience members. It is surprising how much the sound can change once the audience comes in and sits down.
What is a good approach for a home listening room? My friends have a real mix of hard reflective surfaces in the front and absorption in the back and visa versa.
My understanding is that there is a tradeoff which accompanies the increased spaciousness and greater apparent source width (wider image) which arise from that early sidewall reflection: It is early enough and strong enough to degrade the image precision (ime including soundstage depth), and it can be a source of coloration.
Earl Geddes on the subject:
"The earlier and the greater in level the first room reflections are, the worse they are. This aspect of sound perception is controversial. Some believe that all reflections are good because they increase the listener's feeling of space – they increase the spaciousness of the sound. While it is certainly true that all reflections add to spaciousness, the very early ones (< 10 ms.) do so at the sake of imaging and coloration."
Absorbing that early sidewall reflection presents its own set of issues: Absorption is usually going to be more effective at short wavelengths (high frequencies) than at long ones, so there will still be a reflection but it will be devoid of the higher frequencies (the specifics of course depending on the characteristics of the absorbing material). So now we have a reflection whose spectral balance is very significantly different from that of the first-arrival sound, which can be detrimental to perceived timbre, and we also have less reverberant energy surviving to become beneficial late-arriving reflections.
Geddes on spaciousness:
"To achieve good spaciousness in a room requires a multiplicity of lateral reflections (vertical reflections don’t really contribute much) arriving from many directions, i.e. a diffuse sound field. To get the feeling of spaciousness in a small room it must be live, which presents a problem. How does one minimize the early reflections, damp the low frequencies and still allow for a “multiplicity” of later reflections and reverberation? These seem to be completely contradictory requirements. However, with proper loudspeaker and room design and loudspeaker placement this can happen."
One possible solution to the sidewall situation is to use angled reflectors on the side walls to redirect that first reflection so that it misses the primary listening position. Diffusion is another option, as strong and distinct ("specular") reflections are the worst offenders, and diffusion (like re-directed reflection) preserves the spectral content of that energy. And unlike absorption these approaches do not remove reverberant energy, so it is still around to contribute to spaciousness and timbre.
The solution I embrace is to use sufficiently directional main speakers, place them wide apart, and toe them in aggressively, such that their radiation patterns do not significantly illuminate the same-side wall. Instead what happens is, the first significant sidewall reflection of the left speaker is the long, across-the-room bounce off the right-hand side wall, and vice-versa. I learned of this approach from Geddes:
"A reflected signal that arrives at the opposite ear from the direct sound is less perceptible as coloration and image shift than if both signals arrive at the same ear. This is because of head shadowing above about 500 Hz and the fact that our ears can process signals between them. When the two signals arrive at the same ear, the signals are physically merged in space even before they enter the ear and no amount of auditory processing can separate them. When these signals arrive at different ears, the auditory processing system can diminish the adverse effects of these early reflections through cognitive processing between the ears."
I think this is the right direction to go in for your situation, and the Odeons seem to me like very intelligent and competent designs.
If that concrete wall is less than about 5 feet behind your head, then the first reflections off that wall arrive less than 10 milliseconds behind the first-arrival sound. And even if you have a bit more distance than that, it still might make sense to address those first reflections, as they (and other first reflections) contribute to "small room signature", which is something you do not want to have super-imposed atop the spatial cues on the recording.
You might consider an angled reflector or two on the wall behind your head. The idea is to bounce the sound that comes straight from each speaker in a direction that misses the back of your head. It's okay if later reflections arrive from behind; we just want to re-direct the first ones from each speaker if they would otherwise arrive earlier than about 10 milliseconds behind the first-arrival sound.
Thank you sir!!
I have a rug on the wall behind my head at the listening position but I'm not sure it does much.
I think the Odeons will be good if I keep the speakers in the same location as my old ones but if I decide to go with a near-field setup I need to know if the drivers will integrate at a very short distance. I've put the question to some Odeon experts on this forum.
I'm told that the old lathe and plaster has good acoustical damping qualities, which probably helps with bass absorption in your room. I can't tell for sure from the picture but it looks like you had the high frequency reflectors pointed away from you when you had the TubeTraps installed. You don't notice any change in bass quality with the TubeTraps removed?
Having heard Peter's system with the new setting I can confirm that it works. On the other hand, in my own room I need extensive treatment (mostly ASC, with an Acoustics First panel thrown in) for it to work. I suppose guests would run out my room screaming if they would hear it with no acoustic treatment. Hey, even I would run out of my own room screaming
.It all depends on the room. There cannot be hard dogmas about this. My ceiling, for example, needed ASC diffusers, and I can still hear traces of a metallic 'zing' echo upon hand clapping, an echo that had been pretty bad before installing the diffusers. When I do the hand clapping test in Peter's room at the ceiling, it sounds completely benign.
And in my own room, the acoustic treatment does not subtract from liveliness of the sound.
Tim, I've heard the same thing about the horse-hair plaster and lathe. It is incredibly heavy. And I don't think it resonates at as high a frequency as standard sheetrock. It is also not as smooth. My guess is that it is more absorptive and less reflective.
My Tubetraps had the reflective strip pointed back into the corners. I played with them in all directions. Jim Smith liked them best facing each other on each side of the fireplace. That was with my old, smaller speakers. I preferred more absorption with the new speakers until preferred no absorption. I reached a point when I felt my room was overdamped. Bass was a bit tighter before, backgrounds were blacker, images more precise. The sound was less lively, less natural, but perhaps more impressive, if you know what I mean. Now it is freer, more open, more lively, more convincing. Bass is now more hollow with more overtones, more definition, better timbre. It is less upfront and stark or bold sounding. It is less "tight". I would say it is now more colorful and convincing.
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Having heard Peter's system with the new setting I can confirm that it works. On the other hand, in my own room I need extensive treatment (mostly ASC, with an Acoustics First panel thrown in) for it to work. I suppose guests would run out my room screaming if they would hear it with no acoustic treatment. Hey, even I would run out of my own room screaming
It all depends on the room. There cannot be hard dogmas about this. My ceiling, for example, needed ASC diffusers, and I can still hear traces of a metallic 'zing' echo upon hand clapping, an echo that had been pretty bad before installing the diffusers. When I do the hand clapping test in Peter's room at the ceiling, it sounds completely benign.
And in my own room, the acoustic treatment does not subtract from liveliness of the sound.
I agree with this Al, however, your room is more damped and mine is more lively. Your sound is extremely dynamic and does not sound overdamped or robbed of life. However, I think the sound changed quite a bit when you reduced the toe-in of your speakers and it became more lively and energetic. I would love to have your bigger room.
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