[dthoms]

I read all these things about correcting a rooms sound.  What is the perfect listening space...

Should I setup my system in the middle of my backyard?  No reflections, standing waves, etc...

I am not trying to imply that I would do this, but as a newbie to room treatments, I am trying to understand the physical characteristics I am trying to achieve.

[Ethan Winer]

What is the perfect listening space...

The perfect listening space will be totally anechoic at bass frequencies, and less so at mid and high frequencies. The goal is for a perfectly flat response across the entire audible range, at all locations in the room, with no ringing or flutter echo.

Now, as for what's actually practical, that's another story.

Not sure how deep you want to get into this, but my Acoustics FAQ explains pretty much everything you need though it's a lot to read. If that's too much effort, sit back and watch the videos on the RealTraps Videos page. The video How to Set Up and Treat a Room is a good one to start with.

--Ethan

[Kevin Haskins]

There isn't one.   It is like finding the perfect wife.   She doesn't exist.   

There is also some disagreement in even the acoustic treatment industry.   I'd agree with Ethan that the goal down low is anechoic @ bass frequencies but I think most people wouldn't like the results of it.    Most of us are used to listening in rooms and we have become used to the sound.    Speakers are designed around that environment too.    If you operate them in an anechoic environment, you loose much of the perceived output.    In other words, you would have to have a way to design the loudspeaker in the new environment in order to get the correct balance.

We have an anechoic chamber in Northern Seattle that is anechoic down to about 25Hz.   It is great for distortion measurements, but I'd never want to listen to a loudspeaker in it.   

Here is what I'd do if I was designing a room for myself.   

I'd build it separate from the main house on it's own concrete slab.   I'd use 2x6 construction with double layers of drywall.   I'd make it a rectangle, at least 15' wide and I'd probably pick golden ratio dimensions even though it isn't all that important.    High ceilings are a good thing so I'd aim for 10-12' ceilings.     I'd have only one door and it would be a one-man door.   I'd have no windows.    I'd use absorbers (like Ethan makes) across the front wall behind the speakers and in the front corners.   I'd design the rest of the area including the listening seats, and other room furniture before doing anything else.   I'd do whatever cosmetic/living things desired then I'd get good acoustical measurements before going further.    I'd plan on using multiple low frequency devices as put forth by Harmon (Toole) and Gedees.   I'd get the low frequency part worked out first, then I'd work see where the room was in terms of balancing overall reflected energy vs. direct energy from the loudspeakers.    You really have to have that measured data before you can do much more.   

There isn't any one magic device that is going to do it all.   You need to read and learn in order to make good choices.   Even then, you get people with different perspectives.   I'd probably prefer more reflected midrange content than Ethan would advocate.    I don't like too many panels in a room.   

[*Scotty*]

I have an observation to make. I have seen many pictures of AC members listening rooms and it seems that when ever a man cave is involved it usually has the system and something to sit on in the room and very little else. There appears to be a correlation between these mostly empty rooms except for the stereos and complaints about the sound of the owners systems
ranging from boomy bass to harsh highs or brightness. What is the problem with these man caves and is it related to them being a dedicated space compared to an ordinary living room or family room?
Scotty

[Ethan Winer]

Great post Kevin!

I'd agree with Ethan that the goal down low is anechoic @ bass frequencies but I think most people wouldn't like the results of it. Most of us are used to listening in rooms and we have become used to the sound.

Yes, a well-treated room can be an acquired taste. Sometimes it's a shock to people the first time they hear a room with absorbers at the reflection points because they miss the sound of the room. A very large room can get away with less absorption proportionally, but smaller rooms, say 25 by 16 and smaller, need more absorption IMO. To me the issue is that small rooms sound small because all of the reflection boundaries are so close to the listener. In other words, small room ambience is lousy sounding, but larger room ambience is not as damaging. But again, in my experience, once a small room is well treated and you get used to the much clearer and more focused sound, you can never go back.

--Ethan

[Ethan Winer]

There appears to be a correlation between these mostly empty rooms except for the stereos and complaints about the sound of the owners systems ranging from boomy bass to harsh highs or brightness.

It seems to me many "audiophile" rooms are empty simply due to not understanding the importance of room treatment. Magazines have been harping on "gear" for so long, and ignoring treatment, that people just don't know any better. I deal with this all the time, and almost every day someone will tell me their long history of gear purchases, with high hopes, but never achieving the clarity they know is possible because they heard the same speakers elsewhere like a dealer show room. So after trying everything else they finally see the light and come to me.

is it related to them being a dedicated space compared to an ordinary living room or family room?

Many rooms can be set up to sound good. There's nothing wrong with furnishings, but it must be symmetrical and not in the way of the reflection points. So a fabulous room does not need to be empty, but you don't want a fireplace on one side of you and an opening to a hallway on the other, for example. Just yesterday, for fun, I looked through the gallery at Stereophile's web site, and almost without exception the rooms were totally wrong. And this includes many of their reviewers and columnists!

--Ethan

[nyc_paramedic]

Many rooms can be set up to sound good. There's nothing wrong with furnishings, but it must be symmetrical and not in the way of the reflection points. So a fabulous room does not need to be empty, but you don't want a fireplace on one side of you and an opening to a hallway on the other, for example. Just yesterday, for fun, I looked through the gallery at Stereophile's web site, and almost without exception the rooms were totally wrong. And this includes many of their reviewers and columnists!

--Ethan

Ethan,

My smallish(?), 12'7" by 16'7", dedicated apartment listening room has one room entrance that is open. There used to be a door their before I moved in, but the door was not replaced when the apartment was renovated with new sheet rock. The opening to the room is in the corner along the same wall where the listening seat is, i.e., the speakers are setup along the long-wall with the couch against the back wall.

Would installing a door make a positive difference in sound?

[Ethan Winer]

Would installing a door make a positive difference in sound?

An opening is generally a Good Thing. But rotating your setup so the speakers fire the longer way down the room will help a lot. Sitting right in front of a reflecting wall is not a good idea, because that's where the peaks and nulls are worst at all frequencies. More here:

How to set up a room

--Ethan

[JLM]

The perfect room starts with geometry (right size/shape).  The right size and shape is based on physics and individual tastes.  I followed the Cardias prescribed room and setup ratios and am well pleased.  Practically its very difficult to have too big of room.  And typically ceiling heights limit obtaining anything close to the ideal shape of room.  That's why so many of the audio mancaves you find are 8 ft x 13 ft x 22 ft (or there abouts).

The next step is providing full sound isolation.  Even in a freestanding building you could have wind/traffic noise, so the perfect room would be built as a room within a separately enclosed structure.  Insulated staggered double stud walls are a slightly cheaper more practical alternative.  Ventilation noise is another consideration.  Simply using insulated/flexible ductwork takes care of nearly all of that.  Obviously windows and all but one door would be excluded.  An insulated exterior fiberglass door with weather seals provides close to the ideal solution for little additional cost.

Next, clean electrical power is needed.  An underground service with separate transformer, all new appliances (if the service must also serve the house), all new wiring, dedicated audio circuits on their own separate ground, and cryo'd hospital grade receptacles would be almost perfection.  

Next would be room treatments and finally room equalization to provide any finishing touches that take furnishings into account.  My guess about furnishings is that most guys take those pictures when those dedicated audio rooms are new and the clutter hasn't "shown up" yet.  Plus audio is a lonely pursuit, so you only need a single chair if listening is all you're going to do.

The above practical points describes my audio mancave that we built 3 years when we built a new house (the EQ hopefully will happen this year).  Since it was built with the house, the total additional cost to take the space from a simple room to audio mancave was minimal.  It took a bit to get used to the isolation, but that is the real value of the room (to be able to listen to what, when, and how loud I want).  Lack of background noise (and the ability to turn it down and still hear as much) is huge.  BTW my furnishings are nearly all in the opposite end of the room with six GIK 244 panels in the "business" end of the room.  

IMO most audiophiles overspend on amps/speakers compared to the rooms they use.

Scotty, I've noticed a slight improvement in depth of bass with the door open.  But then the furnace kicks on.  

[woodsyi]

I have spent hours and hours and $$$ to make my room sound the way I like, which is the sound of a "lively" acoustic venue.  I like the sound of a room where I can discern different wood tones from instruments.  You have to work at it but you can get there. 

Or for one evening, this will make your room sound perfect for you. 

[nyc_paramedic]

Would installing a door make a positive difference in sound?

An opening is generally a Good Thing. But rotating your setup so the speakers fire the longer way down the room will help a lot. Sitting right in front of a reflecting wall is not a good idea, because that's where the peaks and nulls are worst at all frequencies. More here:

How to set up a room

--Ethan

We spoke about this, on the phone, when I initially ordered some traps. I know your not fond of the long wall setup, but I have been getting some wonderful results this way.

I *did* make it a mission to play with the short wall setup on one of my days off. It sounded just plain awful. Using the Cardas method and many variations of your %38 rule/guideline I could not get decent sound. The base sounded bloated and muddy, so much so that my downstairs neighbor started banging on his ceiling when I was playing tracks at my normal listing levels, and this was at two in the afternoon!! The short wall setup made everything sound very ill defined. This is a living room dedicated to 2 channel listening, so there are no furnishing issues to deal with.

With the B&W Matrix 804's on the long wall, the bass is tight. Sitting on the back wall and with the speakers almost eight feet apart I have a huge, well defined sound stage that stretches from wall (treated with Micro Traps) to wall. And with a near field long wall setup I can listen at lower volumes for longer periods of time without fatigue to my ears or my neighbors.

Compromises, compromises...

[JackD201]

My background is in control room and recording space acoustics so while acoustic principles remain the same my personal approach in designing a room from the ground up differs from the domestic rectangular room paradigm. Having worked in the rooms using Live End - Dead End configurations. I've found I prefer RFZ (Reflection Free Zone) models as I can get closer to the recorded material. More often than not rooms must be fairly large. Deep enough to have sufficient depth from the speaker plane to the rear wall in the order of 6 to 10 feet and wide enough so the loudspeakers can be at least 8 feet apart with enough distance from side walls to have no first reflections from these boundaries aimed squarely at the listening position. To make sure of this I splay the side walls at a rate of at least 2" for every 10 feet. This makes for a trapezoidal room with angles less than 90 degrees where the side walls meet the rear wall. This isn't a good thing so I would use membrane traps from floor to ceiling in these rear corners. Similarly I would deflect ceiling reflections with angled clouds or better yet splay the ceiling as well towards the rear wall with rear ceiling height 10.6 or more high. With this configuration secondary reflection points would be squarely on the rear wall. I could do two things at this point. A room that is too damped is uncomfortable so I would use diffusion predominantly but also leave some absorptive surfaces. So the room would have a ceiling height of at least 10 feet a front wall width of about 25 feet, depth about 30 feet or more avoiding multiples. Using ray tracing I would then use broadband absorption on the now much weaker tertiary reflection regions and probably stop there to leave ample room reinforcement. This geometry has no parallel surfaces so say we can pretty much say standing waves, comb filtering and flutter echo will be much less of an issue. Aesthetically however this room would probably resemble the bridge of the Star Trek Enterprise and wouldn't be too pretty.

I wish I could say I came up with this but if you happen to pick up a copy of MIX magazine you'd find that in the here and now RFZ has pretty much become the new standard. Rectangular rooms have been supplanted by the irregular but symmetrical geometry. From experience I find that this arrangement  yields flat response, great degrees of intelligibility, and if done properly a sense of having no boundaries allowing ambient information from the loudspeakers to determine the size of the recorded venue. In other words your walls will disappear along with your loudspeakers and leave you with a stable and enveloping soundscape.

The world isn't perfect though and not many people will ever really get a chance to build their rooms from scratch. Fortunately there is an array of weapons we normal folks can use to help us deal with the problems inherent in with the space challenged parallel surfaced rooms we're stuck with.

[youngho]

With the B&W Matrix 804's on the long wall, the bass is tight. Sitting on the back wall and with the speakers almost eight feet apart I have a huge, well defined sound stage that stretches from wall (treated with Micro Traps) to wall. And with a near field long wall setup I can listen at lower volumes for longer periods of time without fatigue to my ears or my neighbors.

I wonder whether this is similar to the speaker placement formerly popularized by Audio Physic, which is briefly discussed halfway down the page at http://www.linkwitzlab.com/links.htm. Joachim Gerhard used to be the designer for AP. I believe that the setup entailed setting up the speakers along the long axis, with the listener positioned extremely close to the rear wall. The speakers usually ended up pulled way forward into the room, like halfway or even slightly more, but very wide. This was supposed to minimize the sidewall reflections, the rear wall reflection was supposed to be psychoacoustically integrated into the direct signal through the precedence effect, and I suppose that the odd-order standing waves corresponding to the short axis of the room would not be excited because of the near-nodal placement of the speakers, although the even-order ones would seem to be a big problem. In any case, the boundary gain resulting from the listening position itself would help avoid neighbor annoyance. I'm curious whether you put any absorption directly behind the listening position?

[Ethan Winer]

With the B&W Matrix 804's on the long wall, the bass is tight. Sitting on the back wall and with the speakers almost eight feet apart I have a huge, well defined sound stage that stretches from wall (treated with Micro Traps) to wall.

Well, I can't argue with that! All rooms are different. One potential "advantage" of sitting in front of a long wall is the peaks and nulls that result can potentially align with problem frequencies in the room. So if a room has, for example, a boomy resonance at 100 Hz, sitting with your head 34 inches in front of that wall creates a null that counters the room peaks. This is why I always say that the only way to know for sure where is best is to measure the room response as you experiment with speaker and listener placements.

--Ethan

[Brown]

Would installing a door make a positive difference in sound?

An opening is generally a Good Thing. But rotating your setup so the speakers fire the longer way down the room will help a lot. Sitting right in front of a reflecting wall is not a good idea, because that's where the peaks and nulls are worst at all frequencies. More here:

How to set up a room

--Ethan

Well Ethan all I have to say is THANK YOU VERY MUCH. Your website helped big time. I rearranged my speakers according to your recco. and the system has NEVER sounded better. didn't think I had a bass boom until I relocated everything. Your input is FREE and your help priceless. When I get my job back your panels WILL BE IN MY ROOM. Thanks again.

[nyc_paramedic]

With the B&W Matrix 804's on the long wall, the bass is tight. Sitting on the back wall and with the speakers almost eight feet apart I have a huge, well defined sound stage that stretches from wall (treated with Micro Traps) to wall.

Well, I can't argue with that! All rooms are different. One potential "advantage" of sitting in front of a long wall is the peaks and nulls that result can potentially align with problem frequencies in the room. So if a room has, for example, a boomy resonance at 100 Hz, sitting with your head 34 inches in front of that wall creates a null that counters the room peaks. This is why I always say that the only way to know for sure where is best is to measure the room response as you experiment with speaker and listener placements.

--Ethan

I forgot to add that the bass became tighter and soundstage was wider and more transparent after the Real Traps were installed.

And yes, I still plan on measuring the room response to make sure I don't have any other serious problems. I juts nevrer measured a room before. Any one know of any guides tailored ot the neophyte? Maybe using a PC?

[JoshK]

Well I always take issues with the acoustic guy's suggestions.  The reason is simple.  I've met a lot of audiophiles, and have been to the homes of dozens of them.  I've only seen one where the room shape would qualify.  Everyone else has to do with what they have.

So while its nice to dream of such designs, I suspect for 90% of audiophiles this is just never going to be a reality.  The market is wide open, as I see it, for someone who can do something for the rest of us.

Most rooms I've seen are no where near rectangular, are very open to other spaces in the house, typically are non-symmetrical.  Most of them are also quite a bit smaller than assumptions made on acoustic treatment sites.  This is likely a function of the majority of the homes I've been to were in the greater NYC area where sqft'ge is at a very big premium.

Still I suspect the majority of audiophiles are using their primary living room and have to compromise the layout with their spouse. 

For those with the space and liberty to set their rooms up as you suggest, I am sure the layout is much more ideal.   I just don't know many who have that.  If the sample I've seen is even remotely indicative of the greater population of audiophiles, then these suggestions are just idealistic niceties and not realities.

I have a hypothesis that the lion's share of audiophiles with nice rectangular, symmetric and/or dedicated rooms are in the midwest and/or not near large cities. 

Anecdotally, one of the best rooms I've heard wouldn't fit a single criteria.

[Ethan Winer]

Any one know of any guides tailored ot the neophyte? Maybe using a PC?

I've used ETF for years, but more recently Room EQ Wizard:

ETF, $150

Room EQ Wizard, Freeware

This article explains how I use ETF, but the principles apply to all such programs.

Since you're a RealTraps customer, you're entitled to call or email us directly for more personal service and advice.

--Ethan

[JLM]

JoshK,

As I stated above: "IMO most audiophiles overspend on amps/speakers compared to the rooms they use."

If you can't listen to what you want, when you want, as loud as you want without interuption/distraction/distortion due to the room I recommend headphones for serious listening and settle for cheaper amp/speakers for "background" enjoyment.  If you can't live with the above restrictions its time for a new past time.

The room is the 2nd most important component (after speakers), period.  If you don't agree with that: 1.) You're visiting the wrong circle; and 2.) you should be listening via headphones.

[Rob S.]

Josh K,
Found your thoughts here interesting:

"I have a hypothesis that the lion's share of audiophiles with nice rectangular, symmetric and/or dedicated rooms are in the midwest and/or not near large cities. 

Anecdotally, one of the best rooms I've heard wouldn't fit a single criteria."


I have been thinking something similar just not as detailed.  Cost of living in large cities and apartments/homes may not be that conducive to dedicated rooms,  unless you really do make a ton of money.

You have to share your experience with the room you've heard "that doesn't fit a single criteria"  You've got my attention.   I appreciate your posts and experience about audio.

Rob S.