Just finished the stereo house 9 months ago. Took six months building it and literally 5 years to research all angles to plan for it. Construction is concrete pad, offset stud walls one foot thick, double sheets 5/8" drywall with green glue sandwich. Ceiling is same sheetrock construction but mounted on metal furring hat channels with sound clips. Used 71 cartridges of compound and 21 sealant. All electrical outlets backed with soundproof putty.
Two small windows 4" thick with triple pane. 3" thick solid wood door, mahogany on outside, pine inside. Whisper quiet mini split AC/heat wall mounted unit.
Result is stunning, I hear nothing from the outside, trash truck included, and no one hears a peep of my music from the outside, no matter how loud.
Mission accomplished for sound proofing. For acoustic treatment I worked with Gik and the results are phenomenal. It took me 3 months to tweak in the system and now 6 months later I have completely stopped tweaking anything. Happy and satisfied music lover here with what I accomplished. The construction was nerve wracking at times since no one around this area was familiar with this type of construction, but I really enjoyed guiding those guys along. Great experience.
The model is probably a couple years old. The AC guy had a good deal on it and bought a couple dozen. They have now a newer unit which saves even more power wise. Either unit you get, those things are amazing, way quieter than the noise you hear from a vent when a central AC unit is on. The thing is set on 74 in 100+ degrees in Texas. The thermostat is on a remote control. Never hear it from my seating position EVER. Obviously much superior to central AC for a single room. Only added $20 a month to my bill. Great insulation though...
More detailed info: Offset studs for walls and joists for ceilings are wood. For insulation, used standard fiberglass rolls laid flush against the outer walls, leaving a 2" air gap right behind the double sheetrock. That air gap is a big part of the soundproofing. The top of the ceiling was made of two crisscrossed layers of 1/2" plywood which in essence shaped the room into a fully sealed box. The roof was completely attached on top of the box (the rafters were mounted on top of it) as to not break up the box (another key to soundproofing). Windows do not open. "Soundproof" curtains cut down the liveliness of room when drawn. I find liking some records with them open better (albums lacking in brightness), while bright albums are best with them drawned. Thanks for the nice comments.
Well done effort. My only comment/critique/suggestion is... verify just how much your 2 windows are effecting the sound. I have 2 windows in my room, thought I had them handled via absorption placed and such, then I noticed I had a cheap stethoscope, so I grabbed that and put on some music pretty loud and listened to the window, which is a bit tricky because you're in a room with loud music, but lifting it on and off the glass gives you perspective.... My windows turned out to be quite evil, likely because of how they are mounted to the cinder block building. The resulting improvement was major. So, get a cheap stethoscope for like $5 and see what the sound of your windows really is. If it is making higher pitched than the music noises or screeching noises... I stuck some 2" 30 Duro Sorbothane pucks on the glass and that slowed it down to non-damaging. Cheers.
The mini split is a Daikin 12,000 btu unit. Goes for $1,200 + $800 install. There is an inside and outside unit and it is fairly complicated to do on your own. It is more than sufficient to cool down my 27,000 cubic ft. in a matter of minutes. And you basically can never hear it unless you are right next to it. Amazing unit. My AC guy said I would love it in a music room and he was right. I thank you for your gridfusors suggestion for the front wall. As you may have noticed I have two small windows in that front wall and that would be a no no to any serious audiophile. But I didn't care, I need those windows to view the many beautiful trees in front and relieve me of the claustrophobia I would feel staring for hours at a plain wall. Hence the art work also. That to me is more important than any small sound improvement I may hear from treating the front wall. Something very interesting happened, the TV is mounted on a stand rather than against the wall, and what I found out is the lead vocal would disappear BEHIND the TV. After trying different options, I installed a 4" thick open cell piece of foam about the size of the TV right between the TV and the wall, and magically the lead vocal placed itself in FRONT of the TV. Now my soundstage is perfect to my ears. Another thing is I maintain a great balance between a dead room and a live one because I ordered my 8 bass traps with limiters, therefore it does not absorb high frequencies, just low ones. And with my carpeting it is just what the doctor ordered. Like you say, there was a lot of homework going into this. Thanks a lot to take the time to give me your input. Very much appreciated.
Wonderful space!! So its a separate "building" from the house it looks like? Can you provide details on the split AC unit?
You've done your homework on the construction and room acoustics, well done - the room is prob the most significant "piece" in this hobby, one which I personally am very much into (acoustics). One thing I will mention FWIW on the acoustic side, some QRD type of diffusion on your entire front wall would be something to explore if you ever have the itch. GIK gridfusiors are inexpensive (comparatively speaking) and work really well. Also covering the TV or better yet throw two or three 244 broadband in front. Anyway, great job.
I love the yard too! Mowing close to ..8 acre and all shrubs, irregation etc.. is getting old for me. You have my dream yard, rocks, lol!!