The perfect room
- Thread starter Emlin
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Rodney gold
Im just me...
There is no perfect room...
James
Lord of the Erg\o/s
I used Louden ratios when I designed and built my current house.
The resulting room had a ceiling height of 2.7m, depth of 4.05m and width of 5.8m, which yields a dimensional ratio of 1.5:1:2.15. My loudspeakers are backed against a windowless, double skinned (drywall) and acoustically insulated wall (5.8m wide) and my kit and media are to the right on a short wall. It also helps to have a concrete (and carpeted) floor.
DANOFDANGER
pfm Member
The best room would be one where resonances are kept low to prevent constructive or non-constructive interference. Also adds the right amount of reverberation, early reflections are preffered to late relections.
Small rooms require more treatment as wall proximity has more issues with standing waves and resonances. Larger rooms reduce this problem but as the room size is increased you start introducing late reflection issues such as reverberation and echoes. Which would also require room treatment.
I would think there would be a happy medium where the room is large enough to limit room resonance but small enough for ideal reverberation. I would like to see some reading on that.
Then there is also room dimensions, which goes beyond my scope. Would likely require some knowledge in fluid dynamics to understand. James touches this a bit with room ratios. But then you also have room shapes. For example, a slanted ceiling provides more appealing reflections than a flat one. Perhaps round rooms or other shapes have better acoustics. Beyond me.
Love to hear more on this.
Small rooms require more treatment as wall proximity has more issues with standing waves and resonances. Larger rooms reduce this problem but as the room size is increased you start introducing late reflection issues such as reverberation and echoes. Which would also require room treatment.
I would think there would be a happy medium where the room is large enough to limit room resonance but small enough for ideal reverberation. I would like to see some reading on that.
Then there is also room dimensions, which goes beyond my scope. Would likely require some knowledge in fluid dynamics to understand. James touches this a bit with room ratios. But then you also have room shapes. For example, a slanted ceiling provides more appealing reflections than a flat one. Perhaps round rooms or other shapes have better acoustics. Beyond me.
Love to hear more on this.
Dougunn
pfm Member
Agreed, but it is possible to design a room with as few compromises as possible.
Dimensions and shape would seem to be the obvious starting point, then construction materials. Get these right and any system will be head and shoulders above the same setup in less forgiving surroundings.
This is an area that has always fascinated me. I feel that whenever I hear a system it's the impact of the room that strikes me first.
On a sound per pound basis, spending on the room is, to my mind, the most overlooked (and misunderstood) aspect of getting good sound.
James, I would love to hear more about your purpose built room. Do you have any pictures?
Doug
DANOFDANGER
pfm Member
This is quite true, the fact that a room can make or break a system depending on how it synergizes together shows how impacting it is. Linear speaker systems can sound harsh and boomy in small untreated rooms but in larger treated rooms it can behave more closely to its natural response (linear). To the ametuer enthusiast he would blame the speaker first before the room. Unbeknown to him, he could be disregarding a perfectly sounding system if he or she addressed the area of concern.
zippy
pfm Member
EXCEPT most of us live in 'ordinary' houses and the listening room has to be a living room too. Hence the range of options available to create a perfect room are limited to simple things like carpet/rug/curtain/etc.
darrenyeats
pfm Member
I think this is interesting: http://www.cardas.com/room_setup_golden_trapagon.php.
darrenyeats
pfm Member
Reverberant field isn't bad per se, as long as it's relatively incoherent. Most rooms have enough in them to provide diffusion.
IMV one of the worst things is close specular first reflections from side walls and floor. The speakers should be kept at least 1 meter from side walls (and if not then at least first reflections should be treated) and the floor's first reflection point shouldn't be a hard surface.
Echoes are bad, but IME are not down to larger rooms - culprit would be reflective (e.g. plasterboard), bare, parallel opposite walls in any size of room.
Purité Audio
Trade: Purite Audio
You can treat any room, passively and or actively , speakers which have a cardioid response make a huge difference more direct and less reflected sound.
Keith
Keith
DANOFDANGER
pfm Member
Yes but the lack of recognition is what i am talking about, sure enough what you say is the case for most. But people will quickly blame the speakers before their room.
IMO some reverberance is needed, because we are accustomed to it. But there is a point where more reverb (longer delays) smears the sound.
Wouldnt the priority of treatment and effects be dependent on the dimensions of the room and placement of speakers. So where the area of most concern is, is highly variable depending on these aspects ?.
Well the difference between echo and reverb is the time delay difference. Where that crossover is exactly i think would depend on the length of the sound. But generally the larger the distance between reflections the more it shifts from reverb to echo.
Mike Reed
pfm Member
Since buying my first house in '75, where I gutted the downstairs accommodation, I have always made sure that subsequent properties had potential for an elongated room; preferably with crooks and nannies to break up the rectangle. This has meant knocking down walls and re-shaping the living room, but I've yet to encounter any acoustic problems with dozens of speakers ranging from Isobariks to rear-ported ProAcs to ESLs.
For me, the larger the room the better, within reason. Much easier to fill it than create the space. Back to the wall speakers are fine, but proper imaging/soundstaging comes from having speakers in free space, i.m.o.
For me, the larger the room the better, within reason. Much easier to fill it than create the space. Back to the wall speakers are fine, but proper imaging/soundstaging comes from having speakers in free space, i.m.o.
DANOFDANGER
pfm Member
I do believe you ment nooks and crannies haha ^.^
If not then that would be a tough find with a house lol. I do wonder how that would help acoustically though.
darrenyeats
pfm Member
Agreed, my comments are about exactly these things.
Echoes occur with repeated specular reflections from opposing parallel surfaces. As long as the surfaces have some diffusive features, the reflections become incoherent and there's no recognisable echo. It's not really about time delay, it's about coherent images caused by specular reflection, versus incoherent reverberant field from diffuse reflection. (Or you can make one or both surfaces more absorptive to reduce echo.)
IMV coherent images are disturbing if they are close in time to the direct speaker sound (as in first close specular reflection, as from side walls) - or as you wrote if they repeat (echo).
Mike Reed
pfm Member
DANOFDANGER
pfm Member
Oh that makes sense, thanks.
demotivated
pfm Member
The root of the problem. The system of flat walls, cuboid box and an empty space in the middle of the room is triple balls. The way to make a 'perfect' room is to either:
Have mega absorbent walls to kill reflections. You then either listen to the reflections in the recording and processed multitrack recordings may sound weird [certainly the room would sound creepy. I have been in an anechoic chamber and it's horrible], or you add back synthesised reverb, which studios use routinely.
The best solution is to fill the middle of the room with clutter. Not large flat tables that bounce the sound at your head, but genuine random absorbing objects. This is how Brüel & Kjær designed a test chamber. Of course this is true hardcore bachelor/inverse metrosexual decor. Think moving into new house with everything piled in one room.
Rodney gold
Im just me...
Well, I have a dedicated and fully treated existing room but not built from ground up.. 8 x 6 x 2.5 (m)
My first consideration was to make it a quiet room .. from within and without..I play loudish and above
I built a room within a room for that . all walls panelled with slotted and pierced wood , on battens with rockwool in the air gap..some absorption , some diffusion
I replaced all glass with glass bricks for symmetry , laid acoustic floor , ceiling treatment , power smoothing , soundproof doors , diffusion on the ceiling , tube and flat bass traps in corners etc..
My speakers are well out into the rooms , listening seat is optimised as is listening position and speaker placement and so on
I STILL have to use programs like DIRAC or other DRC software to wring the best out of what is already a good room
At the end of it all there is no universal truth as to what will make a good room as its all taste based.. you work to target curves that please you
My first consideration was to make it a quiet room .. from within and without..I play loudish and above
I built a room within a room for that . all walls panelled with slotted and pierced wood , on battens with rockwool in the air gap..some absorption , some diffusion
I replaced all glass with glass bricks for symmetry , laid acoustic floor , ceiling treatment , power smoothing , soundproof doors , diffusion on the ceiling , tube and flat bass traps in corners etc..
My speakers are well out into the rooms , listening seat is optimised as is listening position and speaker placement and so on
I STILL have to use programs like DIRAC or other DRC software to wring the best out of what is already a good room
At the end of it all there is no universal truth as to what will make a good room as its all taste based.. you work to target curves that please you
tuga
Legal Alien
Round is worst, next comes cube then square plan.
FireMoon
pfm Member
The best room I have ever worked in for mixing was the control room at Strawberry in Stockport. The monitors were recess mounted in the one wall which was curved and "broken up" by consisting of large irregular lumps of rock. The back wall was also non parallel as were either side wall. It's the only room I have ever worked in that had no, to the ear, stand out nodes and you could really whack it up and the sound just grew in size.