New Construction Acoustic Design & Consulting

I need a professional consultant to work with my architect to help build as perfect a listening room over my garage as possible. RIVES is one possibility but I don't want to spend 10K just for the consulting work. I would like to build in as much sound isolation and room treatment as possible like that done for this person:

Could I use ASC as a primary consultant and RIVES for after the room is built to do the final touch ups and room treatment? They only charge $100 for the engineer to help render sketches and make suggestions for the contractor.

I would need detailed plans so that the architect would know how to impliment the built-in bass traps etc. I would need help with the specifics of window and door selection (materials) and placement, room dimensions, ceiling slope, floating floor, isolation etc... Please also see the list of ideas below. RIVES charges a fortune to render drawings based on a computer modeling system. I am not sure all of that makes sense until after the room is built, furnished and then tested, but certainly it is advantageous to build in as much acoustic isolation and treatment as possible from an aesthetic and cost perspective. Please comment on some of the suggestions below:

Room sizes

13X21X8 Feet
14 X18X8 Feet

windows o.k.
According to Dave Wilson

1. pitch ceiling height lower over speakers, higher over listener
2. Build bass traps into the wall
3. Corner loaded bass traps
4. Bass trap all four vertical corners and the ceiling perimeter corner with a soffit bass trap
5. Room dimensions:
Must over-size room by minimum of 6 inches walls, floor, and ceiling to allow for buildouts for acoustic treatments and sound isolation
A. 13-15 feet wide by 15-23 feet long
B. Room height 7-9 feet
must account for additional height of "floating floor"
C. Wall/stud resonance treatment and constrained layer damping: 1. Sandwich two layers of sheetrock. ? Gyproc Soundbloc 1.5 soundproofing plasterboard 2. Suspend sheetrock off studs by screwing into resilient metal fir strips called "z-metal" or "RC-1" 2. Visco damping material {1/16 " thick double sided adhesive visco-elastic sheet} is applied between the z-metal and the first sheet rock layer and a second visco-elastic sheet between the first and second layers. In place
of double sided adhesive visco-elastic sheet, can 100% glue to both sides a layer of sound board {firtex or celotex}. ? Staggered studs. The ceiling must be treated the same way.
D. Locate entry door behind the listner but on a SIDE WALL {nowhere near the speakers since the door will raddle} NOT ON A BACK WALL AND not flush to the corner and at least 2 feet from the corner. Door cannot rattle? Heavy acoustic door/frame?
E. Windows are very tympanic and should be avoided. Tall narrow windows are best.
Must not use standard thermal type instead use 2 layers of thick laminated glass [like that used for glass shelving in stores] separated by at least 4 inches of air space. The air space must be vented into the wall cavity. Set the glass into a bed of visco-elastic damping material. The glass sheets should be of different thicknesses.
F. Lighting should be subdued, indirect, and dimmable. Do not use standard wall dimmers since they will often hum or buzz. Use a variable voltage transformer. Consider low voltage lighting. Do not use ceiling cans, they rattle. The best light has a ceiling bezel and lens of thick rounded glass. Consider creating a false ceiling to hide projector, cabling, HVAC
ventilation big problem if room needs to be airtight to insure adequate sound isolation and room damping from the rest of the house
G. Address side wall, rear wall, and ceiling reflections which are determined by speaker placement. Room dimensions must account for acoustic panels
My thought is that with the amount of $ you are going to spend on the construction of this room, and the kind of equipment I would guess you would go for, the $1K fee is dirt cheap, esp. if it can help you avoid ONE mistake.
I would prefer the 13 x 21 x 8 ft dimensions.

A lot of the points you mention above are good and definitively should be considered in the new room.

Assuming that the room is built well with all the basic elements(many of which you already mention), you may not need any special acoustic treatments.

I say that because based on my experience, speaker placement plays a far, far more significant role that room acoustics and treatments. In fact, I think it was Robert Harley of TAS who said a few months ago that proper speaker placement provides far greater benefit than any room acoustics. Or something like that.

Some to many say room acoustics makes up about 80% of the sound you hear. I'd guess it's probably more like 20% with the room/speaker interaction making up perhaps 50% of the ultimate sound you hear. I'm guessing but I'll bet it's a lot more accurate than the 80% rule.

One thing I would consider adding to your list is a beamed ceiling where the beams are spaced perhaps no more than 3 or 4 ft apart starting at the front (behind the speakers) and then perhaps every 3ft going toward the rear of the room.

Oh yeah, when it comes to furnishing you might consider heavy clothe/cushioned listening chairs or sofas, leaving the leather furniture, tables, floor lamps, etc. for another room. If you need a coffee table of sorts, you might consider a larger cushioned ottoman instead.

I agree on the $1k fee, yes i know you said $10k. I just used Richard on a 12 x 17 room and the $900 he charged was a very "sound" value. If you want him to be able to charge less do some work for him. Fill out his form YOU get from his web site and list all the material you plan on using. The architect you are already paying should tell you that. Draw out the room and specify a level one job. Show each revision from Rives to your architect for the ok and then send it back to Richard. If you want to save you gotta work!
Rives Audio knows what it's doing and doesn't have a vested interest in any specific product. If you were to go to ASC, RPG, PMI, Echo Busters and etc there is an inherent conflict between selling a product and selling a design. There are many good products to use but you need a plan first. I use ASC often for instance but I can't use it all the time. I see too many people throw too much money and ineffective material into the room (I'm not referring to ASC).

I would suggest dividing the problem into sections:

Noise control-mostly lower frequencies

Do you need it. If not then don't make the walls exotic but simple sheetrock, studs and fiberglass. You can do it better but simple walls work quite well.

If you do need it put more massive isolation walls on the outside walls. Sound isolation works regardless of which side of the wall your on.

If you must put the isolating stuff on the inside of the room it gets complicated and you need a consultant. The room sill needs to "breath", "be diaphramatic" or damped.

Small rooms have very distinct bass modes. Speaker and seating positions are very important. Bass traps are a very long story I can't share in one response. I'm already long winded.

Sound Performance-mid to high frequncies

Almost every room needs some form of absorption to make the reverberant energy in the room decay but you need to have a broad band absorption and some diffision. Furniture (soft), bookcases (not completly full), some carpet or a rug or two. Fortunately, smaller rooms need absorptin than big ones. There's a formula you can easily find to estimate the decay time (RT60) for your room. It's always wrong for small rooms but it gives you an idea of how much other soft absorptive stuff you need in the room. Just don't put lots of thin big fiberglass of foam in your room. It's the best way to waste your money.

Lower frequencies<~250Hz

You need to know about the rooms behavior either form testing or modeling. Try CARA CAD. It's a great modeling tool and cheap or buy ETF and test the room or hire a consultant to at least take a look at just this part. Bass behavior is a hard subject.

Last word: Good small room consultants are worth every penny and Rives is one of the better ones.

"there is an inherent conflict between selling a product and selling a design."

What? ...a little knowledge can be dangerous Dbk.

The best and only advice IS to get a good consultant, Bob Hodas or Chris Huston are two of the very best and work for reasonable rates considering there tremendous resumes.

I use Bob Hodas and the people at RPG for all the backup I will ever need to take care of the slightly complicated issues that can occasionally arrive. Clearly taking my own advice at having a relationship with qualified highly experienced people.

The 2nd big hurdle is communicating with your construction contractor to make sure they understand that nothing is arbitrary that the details matter. Look for fear in their eyes, if its there you want to carefully evaluate if these are the guys you want building your room. I am lucky to have a contractor that I have built almost 20 rooms with. The first 5 were very painstaking to work out the specifics of the details and getting the right materials and fixtures. Now we know :) its a little easier.

For the level you imply you wish to achieve you need a real consultant involved with a competent (dealer, acoustician) go between to smooth some minor bumps not just a plan.
I couldn't agree more although there are other competent consulants that maybe be near the site location.
Or you can use a little common sense.

There are no guarantees whatsover that hiring a professional consultant will do a better job than you.

In fact, if your would-be consultant can not demonstrate for you a real system/room combination that s/he designed that absolutely bowls you over with it's sonic presentation across the frequency spectrum, you are probably better off to keep looking for another or perhaps consider taking on this project yourself.

As with some to many things in life, designing a truly superior system and associated room is perhaps more art than science. And "for the level you imply" ultimately, this generally can be accomplished only over a long period of time.

Stehno please, do you really believe that?

"As with some to many things in life, designing a truly superior system and associated room is perhaps more art than science. And "for the level you imply" ultimately, this generally can be accomplished only over a long period of time."

There is no "art" except in the interior design and color selection. Your preference to feel around in the dark and figure stuff out the hard way certainly should be mentioned as a qualifier for your opinion.

Shocking how people with a very high level of investment in audio believe that they have "lucked" into a sound or that it would be impossible to achieve a high level in 45 minutes with the right tools and the right equipment.

This is a science the art was captured by a microphone and from there it is a science of preservation. People who call it art simply don't want to be held to a standard and are taking the intellectually easy way out by not trying to explain what is happening.

I'll tell you what the hardest thing about building a system is, its taking the time to define what you want your system to do and being honest to yourself and everyone else about it. Because if you don't know what you want how can anyone ever deliver something satisfactory?

There is no magic to building a great system, just know how or trial and error.

Cinematic, just to get an idea where you are coming from, what percentage of enthusiasts and professionals do you suppose have truly superior sounding systems?

As for the 'luck' that you flippantly impose on my supposed achievments. Save the the luck category for somebody who needs it, will ya?

As for your statement about being honest to yourself and everyone else. That kind of talk is just plain silly and without substance. But it sounds sooooo good.

A great sounding system is kinda' like an absolute truth. Something is absolutely true whether we believe it or not. I don't make it true and you don't make it false. It either is or isn't true and it stands in and of itself.

One should be able to pretty much say the same thing about a great sounding system, a fine automobile, a fine wine, etc., etc.. Regardless of personal preferences.

I'm not trying to take away anything from those professional consultants who truly know what they are doing. I was simply pointing out that there are absolutely no guarantees that one of these can do a better job.

Surely, you are not saying that all professional audio consultants know what they are doing, are you?


There are never guarantees, but this is obvious. Not getting the right people involved is a mistake in a complex multifaceted project and leaving it to an inexperienced person's common sense doesn't make sense at all.

I don't know what achievements you're discussing, but trial and error is not an efficient or inexpensive process and there is luck involved when you're grasping at straws. What process did you use to assemble your system? I am curious.

"Surely, you are not saying that all professional audio consultants know what they are doing, are you?"

I'd say that most them know 100 times more than any audiophile I know... and don't call me Shirley.
Cinematic, my experience tells me that there are far fewer professionals in this industry that really know what good sound is and how it can be achieved than even I'd care to admit. Whereas you seem to believe that the majority of 'professionals' do know.

For one thing, it is not complex as you say. It's actually rather simple, so long as one knows what they are doing. Mutifaceted? That too makes it sound 'complex'. I suppose if one were to make it seem complex and convince others of the mutifaceted complexities, then perhaps it's easier to sell a product or service.

Nevertheless, I repeat that if a professional consultant cannot demonstrate a system/room combination that s/he designed that absolutely bowls one over with it's sonic presentation, then it is perhaps best to keep looking or take on the project yourself.

Surely, you can appreciate that.

To a certain degree, your response above validates my point.

Whoa guys,

This is about helping a person make good choices for his room. It's not adequate to tell a person that they have to use a good consultant. Neither is it helpful to tell someone that only experience and experimentation is the way to go. I think we'd all like this person to have a good sounding room. To me, for a person with a limited budget, they'd probably be better off using moderation in all things.

Assuming you do it yourself.

Read everything, believe common agreements between individuals and know that no one product will fix all your rooms issues.

Low freqencies are the most dificult so I'd want the dimensions to be reasonable (no cubes or squares) and make the walls bass lossy (thin GWB and fiberglass in the interior). At least that way room modes will be damped a bit. Then experiment with speaker and seating placement.

Mid to high frequency absorbers are easiet to install after the walls are up so maybe wait until the furiniture is in.

If want to use a consultant:

Call dealers, search the web, call your speaker manufacturer to see what they'd like to see in your room or if they know who might help.

I agree there are way to many consultants that don't know how to create a good sounding space and I know there are a few that do. Some of them don't charge much for a phone call or a simple review of plans.
Now there's a consultant worth interviewing!!

Good points, Soundprogression.

i admit i'm biased to the path i choose regarding room design. i had spent 9 years learning and observing cause and effect in my room acoustics and other's rooms. i had read countless articles and opinions......looked at lots of products......spoken to a few different acoustical 'experts'. i had tried to 'bandaid' my own previous room.

i came to the conclusion that even though i had accumulated a good deal of 'feel' for acoustics that if i had the opportunity to start from scratch that getting someone that REALLY knew his stuff......and then allowing them the chance to 'do it all and do it right' was best for me.

consensus is not the path to acoustical truth......this is science applied to art.....get thee a designer that makes sense to you.....your ears will thank you.
In your case, a hired consultant seems to make sense, worth the investment
. You are striving for a perfect room and have a building contractor ready to do the work.
Might be a good idea to have the builder visit several different listening rooms to get an appreciation for acoustics and fine sound.

No offense, but with the amount of time and money you've obviously invested in your system and room, no matter what the end results may be, you'd look rather silly if you admitted a bias toward any other path, don't you think?

Stehno, give it a rest. Instead of criticizing why not go and learn something. Go measure rooms, if you have the aptitude, and listen. The room was engineered along with the best there is. If you doubt it without understanding what it took to obtain it or listening to the attributes of a proper sounding room then keep it to yourself. Because your "IMO" means nothing and has no contributing factors what so ever. You make the nay-sayers of the world look very optiomistic.
Stenersr, where did you fly in from? You must be the new bouncer everybody's talking about.

I made no comment whatsoever about Mike's room. In fact, I like it quite a bit and would deem it as perhaps one of the better rooms I've yet seen. But that's just my perception and ultimately I couldn't tell squat without hearing it combined with his Exquisites and surrounding system.

I don't know who you are, but surely you must know that a room is nothing without a system properly set up and perhaps most importanly, a speaker's interaction with the room thru proper placement. Which by the way, far exceeds the importance of a room's acoustics. Not to mention every part of the system first interacting with the speakers.

But all that is beside the point since I made no comment whatsoever one way or the other about the sonics of Mike's room or his system.

And I suggest that before you develop another butt rash, why don't you reread my previous post. What I said there was only meant to be taken at face value.

BTW, I'm awefully curious how you're little behind landed in this thread so quickly after my last post. Please share.

Stehno, as my article and above post spell out.....i do clearly think that if a person has a relatively 'clean sheet of paper' to start with.....getting a single comprehensive professionally created plan makes the most sense for most audiophiles.......and ultimately worth the money. one must choose the budget and construction quality one is comfortable with. the designer can go modest with treatments or exotic. in any case a cohesive plan is best.

i believe trying to assemble an ecclectic assembly of different acoustical treatments and philosphies into a project without a fundamental scientific and experiencial basis does not have a high probability for success. there are many techie audiophiles that do have the knowledge and experience to design their own room......the issue is a true understanding of acoustical cause and effect.

if i did change my mind on my particular audio path (either regarding gear or room design philosphy) i would admit it even if it might be considered silly. in fact; i have changed directions a few times as i have gone down the learning path as an audiophile......i am currently changing speakers from the very simple Kharma Exquisite to the quite complicated Von Schweikert VR9's. turns out the new room really reveals the shortcomings of the Exquisite in low bass performance. i asked the designer to design the ultimate room.....not the best room for my speakers. if the Exquisites are not up to it.....i'll move on.

in the past i've gone from solid state amps to tubes.......from active pre's to passive......from Wilson's to Kharma's.

if, after a time, i have problems with my room acoustics.....i'll change them. all the bass trapping can be closed up completely or partially and dampning can be added or subtrackted......i don't anticipate any need to do these things.....but i am not so ego-invested that i would forgo changes if that was best. i try to keep my mind and ears open.

i am enjoying my journey and hope to keep learning.
Hi, Mike. Certainly no need to explain and FWIW, your last post seems to be a very sensible position at that.

Perhaps my previous comment sounded a bit sinister and if so, I apologize. But I really did not mean for anything to be read into it other than what it said.

On another note, I was wondering when you'd be changing over to the VS speakers. I heard the Exquisites at your friend's house in Portland.

I don't care what anybody says about their performance, if I could afford them, the Exquisites are the only speaker I'd buy based on their looks alone. (Of course, I'm also quite confident I can make 'em sing like nobody's business.) But I have yet to see a picture do their aesthetics justice.

Anyway, sorry for the comment.

I know a bit about construction and it take alot of character and dedication to get thru a project like Mikes.
Nice to see someone with the money AND good taste.
A beautifully crafted room, somthing to be proud of.

IMHO After reading everything. There has been some good advise.

I just wanted to touch on few things. I would qwestion a floating floor due to lack of coupling between the sub-floor the floating floor and the speakers. Consider sloaping the walls and a coffered ceiling.

Having been a residential remodel carpenter for 5 years of this life, the contractor you choose is every bit as important as the architect or accoustical engineer IMHO. Don't let this job to just any old contractor. I would recomend contacting some accoustical engineers in your area to see which contractors they work with.

Remodel is both art and science for a carpenter find one that loves what they do.

Michael; i assume your post is directed at me. this thread was started by Dbk....who mentioned the 'floating floor'. my floor is directly glued to the concrete and is real wood venier over a composite wood base....very solid. my site is very dry and i keep my room temperature a glued floor will work.

my walls are all non-parallel although they are not sloped.....the ceiling was quite involved....including coffering and chambers.

if you read my article you know my choice of contractor was one that i had a 20 year relationship with. i have done 15 or so projects totaling over $5M with this guy. his forman is an artist and that skill was needed.

i completely agree with your advice and followed it myself.
Stehno, no need to offense taken.

you and i both agree on the 'art' factor of the Exqusites....they always brought me pleasure just looking at them...the VR9's are at best 'industrial'. to be VR9's will be in Piano Black; which should look quite a bit better than the silver at CES.

My mistake, you are correct my comments were ment for DBK.
Thanks everyone for all of your comments. A few more questions:

1. Since the "floating floor" concept seems a bit controvercial, how can I get a solid floor that is uncoupled from the walls and solid even though it is the ceiling of the garage below?

2. What is best for a ceiling design:

A) Custom diffusion panels and soffit base traps
B) "Beamed ceiling where the beams are spaced perhaps no more than 3 or 4 ft apart starting at the front (behind the speakers) and then perhaps every 3ft going toward the rear of the room."
C) Coffered ceiling design
D) Combinations of the above????
Also a few people have suggested that using the diagonal room arrangement one can increase effective room dimensions. Has anyone actually seen this done well. I am trying to image what it would look like and if it makes sense for may attic space since I am limited to a 20 /15 foot room dimension.
Although all the discussion have been interesting, the original questions and limitations you put forward were that you couldn't afford to put out lots of money on a consultant and that you had restrictions on the room dimensions.

Rather than focusing on I'd specifics first I'd ask you to identify clearly, the limitations of the space (size, windows, doors), the actual usage of the room (just you, multi-channel), cosmetic restrictions and the construction costs. After those are clearly identified then work on the practical aspects of the design.

Q. Floating floor
A. Floating floors are most often used to isolate rather than improve the interior acoustics of the room. I prefer to seperate surfaces (walls, ceiling, floors) into two things, lossy or isolating. As Mikelavigne already said he has a concrete floor (concrete is not lossy but is generally isolating) with no floating floor and it sounds great. That probably means that the lossy part is in the construction of the walls, ceiling and acoustical materials (bass absorbers).

I prefer predictable spaces (flat ceiling, parallel walls, shoebox) for the basic structure constructed as a damped diaphramatic shell using sheetrock. There are several good ways to make a wall damped and lossy or damped and isolating (ASC Wall damp system as example). Low frequencies are predicitable. We know pretty close to where the speakers should be and where we should sit. You can always add bass absorbers that changes the shape of the room baised on the needs of the room.

Q. Ceiling Design?
A. As I stated above I like predictable lower frequency spaces but that doesn't mean we can't add more materials to the interior to change the shape and behavior of lower frequecies and up.

Clouds built into, on or suspended from the ceiling work great. The choice of materials is strictly dependent on the rest of the acoustical materials in the room. If you have adequate broad band absorption on the walss then the ceiling usually diffusive concentrated between you and the speakers and over your head. You can use RPG Skylines, Omni's or only the open finished cavities of the floor joists above. or, if you have now where else to put broad and absorption the ceiling is a great place to get it out of the way without usually doing much harm but much good.

Attic spaces with pitched ceilings are an excellect places to suspend a cloud over the pitch or directly attached to the ceiling.

Q. Diagonal rooms
A. Really hard to do well. You have the built in benifit of very low first reflections since the sidewalls fade away but now you have to figure where to sit. Most of the time they work well if you set up the room like a mixing room with the speakers as near field monitors with the rear walls a ways back. Those base modes want to react with the parallel walls even if you have the speakers outside a corner and the rear walls now have first reflections that wouldn't occur otherwise. So you are forever deciding which mode/reflection to treat and mode to avoid/not avoid. Have I seen any work, absolutely. Have I seen more fail, absolutely.

The room size is the room size. The axial modes take precident (LxWxH). The tangentials and oblique modes (longer wavelengths)are general down in strength 6-12dB and only could be benificial if there is a concurrance of a weak axial modes with strong "other" modes.

Please anyone chime in. I really like a discussion of the issues for a non-price no object individual. I'm always interested in technical reasonings and lesser so with anecdotal experiences but they still may be helpful.

Dbk, maybe you could clarify my ealier questions to help us (the forum) help you sharpen your focus.

Rather than focusing on I'd specifics first I'd ask you to identify clearly, the limitations of the space (size, windows, doors), the actual usage of the room (just you, multi-channel), cosmetic restrictions and the construction costs. After those are clearly identified then work on the practical aspects of the design.

Dimensions approximately 17 feet by 20 feet by 8 feet

Two medium sized windows at the front and one rear entry door

Usage essentially just myself and occasional movie viewing via no frills ceiling projector and drop down motorized screen over the windows.

Cosmetic issues...clean and uncluttered, modern space with most of the acoustic treatment built-in

Construction cost including framing, roof buildout and interior finishes (not furniture) no more than 95K
I've run the numbers several times in several ways and the room appears to be too wide to behave well at lower frequencies (<250Hz) If you reduce the width 18" a big potential hole goes away around 50Hz. I don't see any reason why you couldn't have an excellent room given the modest restrictions of the room. You also have the flexiblity of placing your seating and speakers where they will do well.

The cost of the complete build would be between you and your contractor.

I'm an industry insider when it comes to these subjects and need to avoid promoting anyone but if you're spending that kind of money you should have someone help you. I'd look up "acoustical design home theater consultants" in a google search and work your way through a few pages and call some people or just ask people on this forum to give you names. Anyone want to throw out some names? Try RPG's website and go through the residential dealer list. You can except/reject them quickly with a few well framed questions.

Also, you can limit the fee for the consultant's help by reducing his/her responsiblities for inspection and drawing details. If you allow the consultant to drop the complete detail package you should find one that you can afford (try 2-5% of the build out).

Good mid/high frequency acoustical materials are modest in cost with low frequency absorption significantly more. That's the easy part except you need to make it fit the decor. Fancy stretched fabric over acoustical materials (whole walls) costs more than exposed fabric wrapped materials.

Please keep in mind our earlier threads and try to avoid exotic solutions. I'll answer as many more specific questions I can but my available time is limited and I won't be able to follow for awhile.