I built a new house a few years ago and had real fun doing a dedicated audio room.
Dimensions are 20w x 30l and 15ft ceiling. Lots of places can give you 'ideal' dimensions for any size room.
Best thing I did was put the room on the ground floor with a poured concrete floor and radiant heating (no sound of heat system, no baseboard etc.) under carpet. I did not put in a baffling system for the air conditioner; on the other hand I don't spend a lot of time indoors with the system in the heat of summer. When the ac is on in summer I do have some increased background noise. Oh well.
I also used 3/4" wall board. I used standard spacing 16" on the frame but have since heard from folks who used a 12" spacing claiming better results.
I did not put in sound proof windows. My builder felt I might not need them and I think he was correct. I do have one window near my a/c compressors which might benefit but I doubt I'll do it (never say never)
I also put in a dedicated a/c panel, hubble outlets and lines. I did not use any fancy in wall wiring (budget consideration). Lighting is all separate from audio. This was a very good idea. System is dead quiet, no hum, no hiss, no line noise... you get the idea.
As you are a carpenter you might think about integrating room treatment into your design. This is one thing I will do the next time I build a house. :)
You might want to contact Rives Audio (www.rivesaudio.com) for assistance. Consulting with a sound engineering firm like this is another thing I think I would do differently.
Live and learn.
One final thing: the doorway between your audio room and house is a critical choice. I lucked out finding a huge double door at a salvage sale. A poor choice here will be heard! (pun intended)
hints for ceiling, floor and wall treatments - Auralex.com.
Also - search the archives. There's lots on this subject.
Using the "golden ratio" for room dimensions seems quite popular and I feel it has merit. It is 1 : 1.618. Also, I want to add that IMO it shouldn't be a very large room. A large room looks nice and impresses friends but it eats up a ton of power and requires big speakers, both of which limit your equipment options substantially. My future room will be 14x22 and no more.
A local hifi friend of mine has experimented a HUGE amount with room treatments and he has settled on DIY Corning 703 absorbers. You can buy it for about $10/lbs direct from a Corning distributor (check you yellow pages) and it does seem to work very well. I am going to make some bass traps for my system soon this way. Good luck! Arthur
Look at "The Complete Guide to High-end Audio" by Robert Harley. This book has a simplified formula to the science of acoustics. A far superior source is "Sound Studio Construction on a Budget" by F. Alton Everest. This is a terrific source to learn how acoustics work and how our systems work with the room to produce what we here.
Arthur has good intentions with the Golden Ratio, but it has nothing to do with acoustics or audio. I understand there are products being sold using the "Golden Ratio" as the science behind it. This is hype, the "Golden Ratio" is a description of how our body's relate to scale and space. Our body is the "golden Ratio" (Height to width) and in architectural design it tends to be most pleasing. That however has nothing to do with wire or acoustics. Sorry.
Lastly if you do not actually want to learn, find "Rives" on Audiogon. He designs acoustic space for a living and has a huge depth of knowledge.
I second Andy's comments....make sure the room dimensions are not a multiple of the ceiling height.
Wooden frame is good as it will leak the bass out ...producing less reverberation or room modes. If you are going to such trouble you may also consider soffit mouting the speakers, as I have done. It means you need to renovate when (if) you change speakers, however, in theory and in practice this gives the most accurate sound by removing all the comb filtering that you get from bass reflections off the rear wall. An examination of facilities at most high end professional studios will show you that more than 50% use soffit mounted speakers for mains....so don't simply take my word for it.
Also check out Ethan Winner's website on how you might build walls that absorb LF energy....the rear wall behind your listening position and the ceilings usually require the most absorption treatments.
Good luck. Projects can be fun and perhaps you can share photos of your progress (I did)
thanks everyone , ill keep you posted willie
Ethan's site, realtraps.com, is a great place to start reading. Also audiocircle.com has an acoustics circle. This is the most important part of your systems sound next to your speakers. Therefore it will have quite an effect.
You may even want to buy some panels from Ethan, his prices are very good btw. This way you can get some expert advice on your room.
One mistake you want to avoid is to build a room which the dimensions are multiples of one another. I noticed an above poster has a 20'x30' room with a 15' ceiling. This will amplify the peaks and dips in a room. It's pure physics. Being as you have the option on dimensions make sure you don't have the same or a multiple of a dimension, I said that twice on purpose as it's extremely important.
When it comes to the ideal amount of treatment that can be a grey area. In my room I went LEDE (live end dead end) with bass traps in each corner. This has worked out incredibly well. I've had a few speakers in this room besides my Vmps Rm 40's and they all sound better in here. Also it's quiet which helps. Many people think that LEDE is not the way to go and may over damp your room. If it hurt anything I don't know what it is as my dynamics are killer good, I mean the dynamics literally startle you. Imaging is so good I've had newbies ask a few times "where's the sound coming from?".
In the end getting what's considered good acoustics will help the sound of your system and allow it to perform as it should. Regarding room dimensions, did I say to make SURE you don't use the same dimension or a multiple of it?
Another thing I did in my basement room had been to isolate the sound substantially. The living room is directly above my listening room and I like to listen loudly at times. I put in a ceiling starting with soundboard(a layer of drywall I guess is as good), then resilient channel installed asymmetrically, then drywall and then acoustic tiles.
There is drywall that's far better than standard rock and is designed for sound isolation. I just read about it and don't know it's cost. If you're a carpenter then you may already be familiar with resilient channel. There are as good or better methods than what I used available. The result however works great. Only a bit of bass is heard in the living room directly above me.
Best wishes to you for your new room. I love having a dedicated listening room.
Warnerwh, you are right of course. 15ft was a typo. It's actually 12ft - the other dimensions are 33l and 21w to be exact!
What I wanted to say, and others have already done, is that there is a lot of good free help out there to assist in the constructions of a dedicated sound room. But had I to do it all over again, I would have allotted 10-15% of the total cost to a consultant (Rives as the example).
Chsmithmd: I'm glad to hear that your dimensions aren't the ones posted earlier. I had to tell this person how important dimensions are and an idea of dimension ratios but at the same time it appeared an insult to your room. It had left me feeling with somewhat mixed feelings.
If I had it to do over again I'd buy traps from Ethan and send him pics and call him to discuss it. I don't make that much money to afford a consultant to come out but having Rives help I'm sure is worth the investment.
Overall my acoustics are outstanding, at least I've not heard a better sounding system. I'd love to hear another system in a well done room, but done differently than my own. After doing this room and learning how much improvement can be made I'm sold. It's not like you have to "try" to hear the improvement.
In my other house I added a bit of treatment, that helped, so I added more and more. My living room looked horrible but had decent acoustics(I was single). When I fired up my same system in this room it took a while to sink in how incredible the sound was. For the money I consider room treatment a bargain.
Fortunately in my case I had to build a room in the basement of my new house but the dimensions worked out to 12'2"W x17'1"L x 7'2"H. These are decent dimensions. Good thing as I didn't have alot of latitude.
thanks for all the help, I was away for a few days , hence delay.I contacted Rives but their preprinted form is for someone that has a room and not for a new room, I filled it in as best i could but it looked ridiculous so I threw it in the bin. Maybe an email to Ethan is the best. Im stuck with about 300 sq ft max and a height of 8 ft or a little more, so what I want is a suggestion as to the best golden dimension and some ideas on what to build in to the construction. I read acoustic 101 , but there is a lot of really really detailed stuff, which is beyond my grasp. willie
In my experience, your room should be about 16' wide. Mine is appx. 14.5' and seems a little narrow. Double sheetrock and a weatherstripped solid wood door is invaluable. For the ceiling I would opt for the more expensive specialty drywall that is available. There is also a barrier that you can use between the layers of sheetrock that will increase the wall mass without the bulk but I forget what that product is. A nice troweled-on layer of silicone between the sheetrock layers should also help. A length of about 21' should suffice for most applications. If you build your bass traps into the corners from the start it will save you money on treatments. An effective way is to kind of round the room corners with sheetrock and if you can get insulation into that void space created helps tremendously. Just a few thoughts.
Willsandbills, Rives also designs new rooms. You mentioned that your ceiling height may be 8 feet. If so, you do not want a 16' width as Twc recommended. When a dimension is a multiple of another, your standing wave problems generally increase. Since you have an opportunity to build a listening room from scratch, why not maximize the acoustics by consulting an expert.
I am now in correspondence with Ethan and hopefully he will design the room and supply the various bits that he has designed.thanks all,
Don't forget the ceiling measurements with the golden ratio! The ceiling is usually the limiting factor and equally important. For example if the ceiling is 8 feet high, then the length and width of the room must be 13 by 21 feet. If the ceiling is 9 feet, then the other measurements must be 14.5 by 23.5, etc.