Building a house


In the design phase and planning on a dedicated listening room. Any advice on its construction, lessons learned?
neuroop
About the only thing I would do is make sure you have plenty of outlets. Things change over time so installing anything in the wall limits future choices.
Thanks, plan to have a bunch with dedicated outlets for the mono amps. Of course will be doing professional sound treatment after the room is built. Have used vicoustics in my current room. Any other suggestions?
+1 to Russ' comment.

Separate electrical circuits. Ethernet of course. Look into "Rockwool" or similar sound insulation techniques and see if that is of interest.
--10g dedicated line with quality outlets. (Unfortunately some codes require crap safety outlets so you may need to swap these after inspection)  
--if using led lighting, place on a separate line.  Carefully consider lighting options. Ceiling cans are nice for task lighting but I do not like them for when I listen to music.  Have some nice accent lighting options.
--carefully research room dimensions and where you anticipate speaker and listening chair placement.  Can be hard to predict but clearly some dimensions will have fewer standing wave problems than others.
--do you want windows?  I opted out as they are not nice acoustically and I wanted to achieve acoustic symmetry as best I could.
--suggest double dry wall with a layer of "green glue" adhesive
--Crown molding in acoustically your friend.
--Use a solid, heavy door to the room and a seal on the bottom is suggested as well.
1. Double wall construction with staggered studs (one wall's studs DO NOT touch the other, greatly reduces vibration transmission.
2. Line inside of walls with sheet vinyl. 
3. Double sheet rock on inner walls.
4. Electrical outlets close to ceiling to allow for wireless speakers. The more the better.
5. take steps to make heating/cooling as quiet as possible.
All I've got...
good advice given here... only thing i would add is to add a large storage closet to have room for extra stuff, and don't forget how you will do wall hangings, curtains and such for proper room treatment
Don’t hit your thumb, it hurts.. I rebuilt my house and doubled the size, added shops and a basement.. I did it all by hand, by reading books and my family’s collective skills. Something about driving 99% of the nails by hand and fixing most of my mistakes.. No nail guns I couldn't afford them. They were actually not used by Union folks back then. Even the weight of the hammer. The more strike it takes to drive a nail the tighter the bind..
I used dipped galvanised nails. Harder to drive!! Won’t back out.

The electrical was easy for me. Every room outside the main structure including the attic and basement received 220-40 sub panels. I wired from there. Much safer and wiser way to distribute power too. Two separate, 120 legs add breakers as needed. I used 2 50s and added two more 100s per shop... Understand it is a collective load as per code.
I had a 200 amp main. I did some finagling with the inspector to get him happy.. (hid my wire feed) and covered a milling machine and lythe in a shed. ;-)

I recommend you put your hands on every piece of your new house. Look at it, understand what folks are doing, and NOT DOING..

DON’T settle, do it right. DON’T get sold a lot of shi$ you don’t need either.. Remember everything requires maintenance. EVERYTHING...

Here is the key to building your home.. ENJOY IT... Don’t let it happen make sure it happens.. You’ll love it...

Regards
Great responses already provided.Additionally details on points already covered, because these are very important besides other stuff and people need to pay more attention:
1. Size of the room and ratio of length, width and height is important. A ceiling height of at least 9 feet would be great.
2. As much symmetry in the room as possible - consider locations for speaker placement, chair placement and entry door. If you need to have windows, make sure that left and right side windows are symmetric, so that you can treat them equally.
3. If you can make the room sound proof, late night listening can be phenomenal.
Hope you post some pics once the room is done. Good luck!
Professional room treatment begins with design. It is almost silly to give advice however because costs escalate so quickly. Just the advice to have plenty of outlets, which seems solid enough, but every hole in the wall is a sound portal you need to handle. It is not just an outlet, and everything is like that. The door is not just a door, it is a sound portal or acoustic surface. Windows? Gosh I hope you don't have windows but if you do- sound portal, acoustic treatment. On and on.

It will help to have some kind of budget, and realistic expectations. Also I know everyone says the room is so important, and it is. But never forget the room is really just one more component in a system in which every component matters. And quite honestly, they all matter about the same. Also if the room will be in a house, well then it is just another part of the house. No one even including Jay Leno would put a $5M garage on a $.5M home. Well Leno might. But no one else. And so as always, a sense of proportion will serve you well.
Had a house built and made an effort to get a first class sound room.  Lath & Plaster walls & ceiling. Soundproofing inside the walls and an exterior weight door to minimize disturbing the wife.  Dimensions not especially large (is it12'X11X8'?) but I'm a guy who prefers tone quality & soundstaging over bass & deafness. I'm mainly a classical guy. Gorgeous Eucalyptus bare floor sourced from local wood. Double-glazed windows. No acoustic treatment other than a couple thousand LPs. What can I say? I love the sound I'm getting. There's a picture (edcyn's system) in this crazy website's picture ghetto.
Check out my house of stereo system. It probably contains most of the info you are looking for.
Room is the most important piece of the audio puzzle. Go out to expert sites like Cardas, Acoustic Fields, and read Jim Smith’s get better sound book. Room dimensions are forever so get them right in the beginning.
Pull multiple 20amp dedicated circuits to the areas you will be setting up your equipment (read job m smith’s book on this too).
Use wired Ethernet for your audio equipment and make sure you have good access to 5ghz wifi to use your ipad/iPhone to control your music app like Roon or others.
Maybe  a bit more than  you need...maybe not.
And a bit of a different problem
I'm an architect doing larger scale projects, namely Educational. Often the program involves a Music Room....an instructional music class for instruments. Sometimes to listen to recorded music  as well, but not always.
This is different from a home in that has to put up with a certain level of use that you won't experience.
The construction is meant to isolate the space from other adjacent spaces. I have  done suspended and isolated floor systems, as much to isolate it from adjacent spaces but also  from  the resonant nature of the structure.  Ceilings also are a special consideration with very specific suspension methods.
At the front of all of this are the room proportions
A great way to block sound transfer in addition to the the 2" x  6" staggered studs, is to put a layer of mass loaded vinyl between layers of drywall, or at least between the studs and drywall.  And it's not that expensive. 
Decide where your gear will reside and run in wall speaker wires to other rooms so can have many places to listen and compare not just one.
Also have all the walls and floor and ceiling, as applicable, of your main room insulated ( internal too not just external walls) and install solid wood doors not hollow there so you can have some volume at night and not disturb the family.
That’s what I did. Provides a lot of flexibility for enjoying your hifi in more rooms and any time of the day
I know the guy who actually started his house construction with basement as a listening room and everything else was built on top of it just as an secondary addition... can you imagine six layers of different sound benefiting materials in the basement floor!? You could say that the guy is crazy, but the think is real. 
Open cell foam on all cavities. Dedicated outlets. Been a builder for 30yrs.  Good luck. 
If you're married have your better half sign off on absolutely everything you are going to do beforehand. My mistake was getting her to sign off on this being my room alone to do with what I wanted. Thirty years later complaints were still coming in, fortunately only sporadically.

Plan  room entrances and walkways carefully so as to not interfere with speaker placement. I messed up on this and now have to place speakers much closer to the walls than would be ideal, and had to avoid ported speakers due to the wall's proximity.

Another small issue is not to have a couch for your prime listening spot that has the crack between it's cushions exactly where you need to sit. That alone will provide a daily annoyance that can last you years on end. 
Plan the rooms decor to go with your speakers, or vice versa. That helps on the marital front too.

You've gotten a lot of good suggestions on this thread so far.. Good luck with the construction. 

Mike
In case it wasn't obvious, the electrical outlets close to ceiling are for home-theater/surround-sound wireless speakers.
HVAC guys don’t like sealed rooms. Air in needs an air out.
Like me you are really fortunate to be able to start from zero with your listening room.  I had been doing hi-fi for 50 years before my chance came.
There are already some great suggestions above, so I won't repeat any of those..

My room is in the basement.  As I've said in other posts this gives real advantage by enabling all equipment to be in hard contact with the floor/ground so it cannot move or vibrate, causing distortion of the signal and corruption of the soundstage.  Ensure the mass loading is maximised by using heavy support materials.

A basement siting also removes the temptation to include windows.  Glass is about the hardest most reflective substance there is and can reflect sound waves behind curtains and blinds.  Concert halls and recording studios don't have windows.

With an empty page, acoustic design starts from scratch.  So there is every chance to get it exactly right.  There is a temptation to over-damp with thick layers of padding on the walls and thick rugs. Even ceiling treatment.  This is not the best way to go, some sound reflection is required, to create a realistic soundstage and room boundaries.  So I very strongly recommend paying for an acoustician with relevant expertise and experience to advise; the price will be very small relative to the overall construction cost.

Prepare for a shock.  You will have a bigger sound quality upgrade than an order of magnitude more expenditure on equipment, wires, tweaks, the lot.
AVOID a windowless basement!
I really appreciate all of the great advice and thoughts. The house will be 1 floor and no basement. Fortunately my wife has a hands off approach to this project (she gets to do the rest of the house). The room will be rectangular with 12 foot ceiling. Several of you mention the "right proportions" - opinions on what these proportions are? Thanks again!
Do you have a turntable that you will be using for more than 50% of your listening? If yes look at isolating the turntable. You will loose the option to move it but I had a cement pad installed into the floor that is suspended or supported by the foundation walls not the floor joists. I have no vibrations or issues when someone walks in the room. The other method I have heard of is creating a support stricture in the wall studs tied into the foundation for a wall mount turntable bracket.
also don’t forget to run quality Ethernet wire for internet connection. Wireless is only a tool of convince always hard wire your streaming source.
Lighting I mounted crown 6 inched down from the wall ceiling intersection and dropped color changing, dimming  led strips. This allows you to create any mood setting you like.
- The planning phase is where you determine that ultimate potential that your room will have. Your system will never be any better than the room will allow it to be.
- I've been designing, calibrating and treating systems and rooms for the past 14 years, and it's much easier to work it out on paper/computer than to "fix" it later.
- Proportions are absolutely critical, so figure out the max footprint you have to work with and then work through the various tables that give you best-case scenarios for minimizing standing waves for a room that will fit that footprint. All else being equal, a bigger room is better to a point, as the severity of modal problems tend to be less in a bigger room.
- Ideally, try to acoustically separate the room from the rest of the house if you have anyone to answer to for excessive SPL's - money well-spent on the room versus spending it on a lawyer later. This includes structural isolation and acoustic treatments. If you're doing a slab floor there are ways to isolate and properly treat that. If you'll have a wood-framed floor under the room, be extra careful in the design phase, as a wood floor system becomes a type of passive radiator with a very substantial resonant frequency that can ruin an otherwise great room.
- Pay attention to what the eventual decay time (RT-60) will be in the room - this can be approximated by computer model, and there are guidelines for what's appropriate depending on whether or not you'll be listening to 2-channel music or surround sound A/V.
- Be sure to make the back of the room slightly more acoustically "alive" than the front.
- Expect to balance diffusion/absorption/reflection with room treatments in the final phase - all the computer simulations in the world won't be any replacement for in-room measurements and calibration once the system and furniture are actually in that room.
- Home-run 10ga. feeds to the head-end outlets, ideally from an isolated sub-panel.
- Glass isn't nearly as bad acoustically as one might think, but it does tend to let in a lot of outside noise, so I'd try to minimize the glass and keep it away from the front of the room or the first reflection points.
- And finally, if you can design the room to include infinite baffle subs...do it! I built my home back in PA 24 years ago, and was able to integrate infinite baffle subs into my listening room, and have used them in a world-class ground-up listening room build, and there is nothing like them. Effortless bass down to 10Hz, magnificent harmonic richness that carries up into the midrange, unmatched punch and dynamics. I moved to NM 4 years ago into a house with no IB option, and not a day goes by that I don't miss them. You have to design the room around them, but if you can pull it off, you will be rewarded. Be sure to computer model the room and place them properly in the design phase, as they become part of the structure of the room and can't be moved in the future; putting them in an acoustic null or peak will be a problem that only EQ can minimize, and that will neuter the bass.
- Take your time and get it right now, and you'll enjoy that system forever.
Hope that helps!
Thanks sgreg1 I do use a turntable for substantial listening. Will look into your suggestion.
Thanks audiophilenm, how does one go about computer modeling the room?
Neurop
Building a room as we speak. Couple of thoughts. Get the room dimensions as ideal as practical. Your challenge will always be bass management and keeping your noise away from the rest of the home. High ceiling is preferred. Generally speaking, steel joists are preferred over wood. 24” OC better than 16”.
For not much additional cost, frame room with 8, 10, or even 12” studs and plan to incorporate, integrate, bass traps into the walls, ceiling, floor etc to keep your room open as real estate is expensive. You will thank yourself later on. Bass management is one of most expensive elements to do correctly. Everyone’s advice is spot on from mass loaded vinyl, to double 5/8 gypsum, double walls if possible. Also, your weak link will be your windows. Tuff WAF, but best not to have any, especially at the listening level. Windows with STF’s above 50 will cost you. Door(s), 2 solid core doors separated by an air lock. Affordable. Try and float the floor with a sound absorbing mat, 2 layers of 3/4 ply and some green glue or similar in between if not on concrete. Don’t allow wall and floors to touch. Seperate by 1/8 to 1/4” and fill in with acoustical calk. Plug ALL penetrations (no jokes please), especially outlets with putty pads or similar. More details on line. Best. 

Be careful with the 12 foot ceiling dimension relative to the other two of the rectangular box.  Understand the difference between sound isolation (soundproofing) and acoustics.  Isolation is a science, acoustics an art. Only thing to add about isolation is close up every hole and gap with acoustic sealant and put seals on the door because that’s where the sound will escape. And don’t be surprised if the low frequencies still get out after doing all of the other soundproofing.  Design for flexibility in speaker placement and seating position.  If your room is 12x12x12 change it.  First time post from an architect. 
Room dimensions?
Two options:
1. Golden Ratio - Used in architecture
2. Fibonacci numbers - Used in Nature
Google them...
+1 consonance

Take a lot of pictures during the process, I mean a lot.  Takes very little
effort and you'll be glad you did at some point.  Use a tape measure to show stud locations.  Don't forget the ceiling!  You may need those for hanging acoustic treatments.  Have fun.

Regards,
barts
YEs good point....locate your best equipment in the basement on that solid concrete foundation...best tweak ever is for floors to not vibrate .......finish with dense thin pad and carpet.

Good proportions, solid wood floors, large Persian rug with proper heavy felt underlay, wood paneled walls, rock wall, wall paper or flat paint, crown moulding, acoustic ceiling. And no glazed artwork.

Yes I said acoustic ceiling!
I know a everyone thinks these are out of style...and the soft, asbestos-laden ones are. But the early, concrete-like ones, are not just good, they're phenomenal.

My last house had one of the ceilings as well as all those other features including a rock wall. It was a mid century modern time capsule that I bought from the original owners. It wasn't perfect...but was easily the best sounding room ever I've been in.  Meaning the clearest mid-bass and lower bass I've ever experienced. Super clean. Deep and tall soundstage. Soundstage did lack width. But it was good enough. Excellent high end too. It was not a dead room. It was a room with a lot of diffusion and very little absorption but it worked. It was also 16' x 32'.

There was not a shiny thing in that room. All artwork was tapestry, wood-carved or textured.

I have moved all over the country for work and have taken my stereo with me. I've been fortunate to have some great spaces to listen in.
The best rooms had acoustic ceilings in common.





Do the Jim Smith Tour $500

No parallel walls.


Prime number dimensions


Run dedicated lines to two opposite sides for flexibility. 


Don't be too anal.
Robert Harley of Absolute Sound designed (and helped build) his own listening room, and has written a lot about it. It is well worth reading.
https://www.theabsolutesound.com/articles/building-a-listening-room

EXCERPT:
"Planning the Room: Size and Dimensional Ratio

The first step in any room design is choosing the room’s size and dimensional ratios—the ratio of the length to the width to the height. This ratio has a very large effect on the room’s sound, particularly in the bass. Good room ratios spread out the room’s resonant modes more evenly, resulting in smoother and more linear bottom octaves. Explaining the importance of room ratios is beyond the scope of this article (The Complete Guide to High-End Audio’s chapter on room acoustics breaks it down), but know that the length-to-width-to-height ratio is the crucial starting point.

Fortunately, acoustic-design consultant John Brant has created an excellent tool on his website (jhbrandt.net) for evaluating room dimensions. The free downloadable spreadsheet performs a detailed acoustical analysis on any set of ratios that you enter. The tool plots all the resonance modes graphically, shows you if the resonance distribution meets the “Bonello Criterion,” and suggests ideal ratios, among other analyses. In addition to the dimensional-ratio spreadsheet, the site includes many other valuable resources for room design. Art Noxon, founder of Acoustic Sciences Corporation, inventor of the famous Tube Trap, and consultant on my room explains room ratios in the sidebar accompanying this article.

In practice, the listening room’s dimensions are also influenced by real-world considerations such as the amount of real estate you’re prepared to commit to the room and how the room fits into the floorplan of the rest of the house. It’s easy to forget that the listening room is just one part of a house and must integrate with the rest of that house in many ways. Keep in mind that good room ratios span a spectrum in which you’ll get good sound. Generally, the larger the room the better the sound (assuming good dimensional ratios); a large room spreads out the resonance modes more smoothly than a small room does, resulting in flatter bass. My room is 27′ long and 17′ wide, and the ceiling is 11′ tall. After living with the finished room for about three months at the time of this writing, I’m very happy with the size and feel of the space.

Once you’ve decided on the room’s dimensions, the next consideration is the room’s wall construction. There’s a wide spectrum of framing and construction techniques that improve the room’s sound quality as well keep sound in the listening room from getting into the rest of the house. You must decide how important this sound-proofing is to domestic harmony, and then choose the wall-construction technique that fits your budget and needs. I’ll share with you just a few examples of the vast range of wall constructions. But first you should know that a wall’s “transmission loss” (reduction in sound amplitude from one side of the wall to the other) is specified as an STC (“sound transmission class”) rating. The higher the number the greater the wall’s attenuation of sound. A standard 2×4 wood-framed wall (16″ on-center) filled with insulation and with 1/2″ gypsum board (drywall) on both sides is specified as STC-35—not a very high value. With music playing at a moderate level inside this room, standing just outside the room you would be able to clearly hear and identify the music. The next step up is to use 2×6 plate with 2×4 studs that are staggered. This costs next to nothing, but increases the STC rating. For a nominal additional cost you can use 5/8″ Type X Sheetrock on the wall outside the listening room and gain a few dB of additional transmission loss. Acoustic supply houses sell gypsum board composed of two layers of gypsum separated by a viscoelastic polymer (SoundBreak XP from National Gypsum, for example) that blocks more sound than does conventional drywall. You can also hang vinyl material inside the wall for even greater isolation. Double drywall adds to the transmission loss. I’ve mentioned this small sample of materials and techniques to illustrate that you can dial-in the amount of isolation you need, and balance it against your budget, with great precision. The gypsum board manufacturers (USG and National Gypsum, for examples) publish a wealth of useful information about the various wall-construction techniques and their sound-blocking performances. As Art Noxon explains in the sidebar, however, soundproofing and optimizing audio quality inside the listening room is more complex than simple soundproofing. The wall inside the listening room should be treated very differently from the wall outside the listening room, as we’ll see.

One of the problems of frame construction is that bass energy from inside the listening room puts the wooden-frame-and-drywall structure into motion—a bass impact, for example, makes the wall move. That wall motion, unfortunately, converts the stored mechanical energy in the wall back into sound after the transient is over (Fig. 1). Art Noxon has called this phenomenon “wall shudder.” Wall shudder colors the bass tonally because the walls will vibrate at their natural resonant frequencies, adding energy at that frequency. Moreover, the wall movement is chaotic. It doesn’t take much wall motion to hear tonal coloration because the acoustic output of a vibrating object is a function of the object’s excursion (how far it moves) and its surface area. With a large surface area such as a wall, even a very small excursion can produce an acoustic output.

Wall shudder also distorts music’s dynamics. Some of the transient’s acoustic energy is turned into structural resonance of the wall, diminishing the transient’s attack and thus the sense of suddenness and dynamic life. Then, as the wall releases that energy over time, the transient’s decay is smeared. The result is a distortion of an instrument’s dynamic envelope and thus a diminution of music’s dynamic expression. Moreover, wall shudder masks the delicate spatial cues that our brains need to form the sense of a fully developed soundstage, the space within it, and the impression of bloom and air around instrumental outlines. All these subtle forms of distortion add up and contribute to a hi-fi system sounding like a facsimile rather than like the real thing.

Another way in which listening rooms color the sound is familiar to anyone who has set up a full-range speaker: tubby and lumpy bass. The listening room selectively reinforces some frequencies and cancels others, with the frequencies reinforced and canceled determined by the room’s dimensions and the speakers’ and listener’s positions. This is one reason why some sort of bass trap is essential in every room.

To summarize, the three primary problems inherent in music-listening rooms are: 1) sound leaking from the music room into the rest of the house; 2) wall shudder; and 3) excess bass that requires bass traps in the listening room..."

Might be fun for you to read early Absolute Sound mags from the early 70’s that describes JWC’s transmission line that he built into his house. Pretty extreme!
Excellent! Lots of information to digest. Thanks everyone.
02-27-2021 6:15amHow does one go about computer modeling the room?

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DON’T settle, do it right. DON’T get sold a lot of shi$ you don’t need either.

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It only cost YOU money, just like I said. Watch your money and it will go a long ways..

You already have a GREAT model, now refine it.  If you notice what was said;

"all the computer simulations in the world won't be any replacement for in-room measurements and calibration once the system and furniture are actually in that room."

I'm gonna add get to know your room, listen. I have a room that was designed with IB in mind with built in equipment racks between the two 
They ARE 120 cf pockets HUGE. Traps and IB pockets.. That was the plan 35 years ago.. JUST now getting to it.. Broken necks, heart attacks and Covid.. Talk about the brakes getting applied..

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Though the suggestions are grand I also noticed this part also;

"answer to for excessive SPL's - money well-spent on the room versus spending it on a lawyer later."

When you hire someone to plan out your sound room, guess what, THEY screw up YOU have to get the Lawyer. The NOISE complaint will have nothing to do with them. It's a NOISE complaint, not a music complaint.

Now if the chandeliers start keeping beat in the neighbors house, when your listening to your 45s at 70 db that might be an issue.

As for doing it right first, you have, READ A BOOK and don't second guess your own ideas.

Just don't try to make round rooms work, they won't.

I read "Isolate the sound room" Horse pucky, studios are nice, so are integrated sound rooms, nothing I like more that to be able to hear music while I'm cooking.. I'm THE COOK. I OPEN two french doors and draw heavy curtains in front of that opening while in concert. They act as wiers. 

Windows? nothing wrong with windows or doors. Don't get hollow core doors and I don't think you can buy a cheap noisy window anymore, code won't let you..How they look that's up yo you. I want more than one way out. I don't enter rooms with ONE door EVER.. Have have a least a window and a stool, so I can break out the window.. NO EXEPTIONS!!

Regards
Don't use or allow nails.
Screws don't 'back out', esp. since new lumber is generally wet.  Unless you spec 'kiln dried' #1.  But screw everything anyway.

I've seen some really 'cretin' nail gun connections, to the point of a intersect looking like Pinhead on a 'bad hair day'...
If you live in an area prone to a lot of lightning, underground transmission lines and/or a master disconnect. Also, avoid anything outside that can conduct electricity. A strike can come from someplace other than the transmission lines (a reason a whole house surge protector is not as effective as "local" ones which are not as effective as unplugging the components.)
Completed my two channel listening room a bit over a year ago. The quality of silence is surprising; guests remarked upon it as soon as they entered, in pre-Covid days.

Dimensions. Snake oil abounds. Fortunately, the real science has been done, at the University of Salford (UK), in their School of Acoustics. The famous Cox teaches there. They ran 100,000's of simulations to arrive at optimal ratios - they found that MOST rectangular dimensions are bad, a quarter are OK, and a few percent are good.

Stereophile ran an article about two years ago on construction techniques. They stressed rigidity and glue. I used an elastomeric glue that never quite dries, and it's elastomeric counterpart caulking, called Build Secure and M1 respectively (from Chemlink).

Walls and ceiling used 6 layer drywall including an embedded layer of sheet steel, called Quietrock 545. The manufacturer is knowledgeable and very accommodating. Construction techniques are also discussed on their website.

Isolation transformers tend to hum when they are doing their job. Best to site them outside the listening room. Don't forget air lines - you just may end up with an air bearing TT or tonearm, or both.

Good luck!!!

Absolute Sound, not Stereophile, my mistake.
Lots of good suggestions here. I incorporated many/most of them when I built a 38x28 addition on the end of our home. Concrete floor with extra foundation against earthquakes (it IS California!). Double offset stud walls using 2x6s, soundproofing, double door into room from remainder of house with one door constructed with internal sound deadening, etc. The only suggestion I would add that I did not see above is to avoid a flat ceiling (maybe I missed it); mine ranges between 8 and 10 feet peaking off center. Sonics are superb and my son's blues band uses it for practice and recording. Good luck.
Thanks again everyone - now discussing with the architect
It dawned on me that if you are setting up a permanent home-theater (i.e. will always be in same location), you should probably put some electrical outlets in the floor where your seating will be. Modern HT chairs have USB outlets, motors and regular outlets built in. and you don't want wires to trip over if you plug them into wall outlets.
Thx, not planning on a home theater