Building a new room


Hello All,

I will be using a contractor to build a new dedicated audio room in the basement. The room dimensions will roughly be 19'X14'X8'.

Three walls are already finished and are concrete walls behind dry walls. I am thinking of making the third wall with 2X4s and double dry per side with Green Glue used between them. Also plan to add 10-gauge wire for a dedicated audio circuit. I believe this should be 20-amp circuit?. Also will not go with can light. Instead would prefer the ceiling spot lights. Do not plan to run a separate ground, as of now.

What insulation have folks used before for sound proofing? I was at Menyards for picking the Green Glue and came across UltraTouch+ denim insulation. Does this work better in dry walls and in ceilings?

What other points am I missing or should be taking care? Please share your experiences.
128x128milpai
A room is an adventure, yet it is the most important 'component' you will ever buy. I built a room years ago. Some things to consider: build up the floor over 2x4's and sheeting and then lay carpet; use dimmers that are RF proof; if your heating plant is in the basement you need to isolate it otherwise the noise will seep into the room. I put mine on isolation pads and treated the duct work with sound proofing; consider a separate electrical panel and service to service just that room; hopefully the dry wall was glued and not screwed to the studs. Plan to pull the speakers out from the wall, at least to a point they are in a 'third' point in the room. Keep all your gear on a side wall and out of the speakers first reflection points. Be prepared to do acoustic tweaks for a few months to you get 'better sound', like Jim Smith recommends. Enjoy.
We recently finished a Home Theater room of very similar dimensions. At each corner we brought the wall in at a 45 degree angle a couple of feet to avoid the traditional standing waves problems associated with most rectangular rooms. Placing the speakers then against the flat corners and positioning the seating to the natural crossing points has created a 'sweet seat' area that is truly spectacular with good source material. As far as a dedicated circuit, flooring, etc...I basically agree with what has been said to this point.
Buconero117,
The furnace is in the basement and will be behind the new 4th wall. Hence I want to use double dry walls on both sides for this 4th wall. The furnace is already in place - so I cannot put isolation pads underneath it. Hence I want to know what type of isolation pads to use in this 4th wall being built? Regular fiberglass or the one I mentioned above? I do not have the speaker cables to move the equipment to one side. I can get that done at a later point. For right now, I can get a stand that is lower and place my equipment between the speakers. I also plan to get some Hubble IG outlets at couple of places. Yes, I am ready to do some acoustic tweaks.

Brauser,
I have some GIKs for the bass trap. Hence do not plan to do the wall at 45 degrees. I do plan to get the speakers at least 4 feet from front wall and 3 feet from side walls. It will all depend on how the speakers sound in that room.
I don't know if its possible for you, but I tend to like ceilings that have some type of slope to them. Start at, say, 8ft in the front of the room, and have it end at 9 or 10 feet at the end.
I built a room using Quietrock. Double stud with Quietrock 545 on each side. The STC of this construction is 80 dB (very quiet). The Quietrock web page has excellent, easy to read white pages of building a music room with sound insulation. Enjoy your process.
Zd542,
Unfortunately the ceiling cannot go above 8 feet.

Rgwrjs,
I will talk to my contractor on the Quietrock. Thanks for the tip.

I also plan to look into some good AC outlet ports. Looking into Porter Ports. Fellow audiogoner Lak has indicated that he has had very good experiences with Porter Ports. I will also read about others before deciding which one to go with.
"03-03-15: Milpai
Zd542,
Unfortunately the ceiling cannot go above 8 feet."

Not to worry, the bill for the system and the new room may go over 8ft. So at least you'll have something that high.

For outlets and related accessories, try The Cable Company (www.fatwyre.com). They probably have the biggest selection and they know what they are talking about. They will even send you demo units of anything you are interested in to try first.
Power outlets can cost a fortune, but if you look for 'hospital grade' outlets they will be better, and often they cost about 20% of those in the audio trade. Also, you mentioned being stuck with current cables for the speakers. Please consider a trip to HomeDepot and get some 12 gauge speaker wire, its very inexpensive and I bet you will find it much better then what you are using. Ceiling should be acoustical tile, rough pebble finish will tame resonances that a flat, sheet rock ceiling will produce.
Yes, I did look at The Cable Company and inquired about the Furutech GTX-D R.
I had a question on "dedicated line[s]". Why do people have 2 or more dedicated lines? One for amp and one for other equipment?
Don't worry too much about outlets they can always be changed later. Concentrate on the things that must be installed before the walls are closed in.

Such as, install at least 3 dedicated outlets without any junctions or tie ins. Use at least 10 gauge wire.
You can then install a line for other outlets and a line for overhead or side wall lights.
I also ran cat 7 cable and cable TV and telephone jacks.
If the room may also be used for home theater run the best speaker cable you can afford from the front of the room to the back and sides.

Yes, use insulation inside the walls but don't just butt the 2x4 tight against the concrete walls, leave a gap.

On the ceiling, I used 2 layers of 5/8" drywall, the second layer is glued to the first before final screwing. I wish I had double layered the drywall walls but you may want to.
Buconero117,
I plan to use Albert Porter's Ports which are cryo Hubble made to his specs. As far as speaker cables are concerned, I have a different view point than you - so lets not go there. I currently have a drop-in ceiling that the previous owner did in the basement, but I want the ceiling higher. I will try to research on acoustical tile.

Ozzy,
My question is - when people have dedicated outlets, do they use them to directly connect the device (amp, preamp, cd player) to the outlets? I plan to use the outlet to connect my power conditioner and then the devices into the power conditioner. I have looked at a youtube video of MIT Z-Duplex, which is a in-wall power conditioner. It shows how the noise is cleaned when using that. I don't know how it would affect the performance of the amps when plugged into such outlet.
The room already has a home theater wires in the front and back. I plan to put a dummy box on those corners and keep them ready if I move in future. As of now - no interest in home theater. Yes, considering the CAT5 cables. What type of insulation do you suggest - regular fibreglass or other alternatives?
2 of my walls - I plan to double layer using Green Glue. I had not thought about this for the ceiling. I read that you have to use isolation clips to decouple the joist and drywall for the ceiling to be really soundproof. So I am not sure if the 2 layers in the ceiling would help me. Most of my listening is done in the night when kids are in bed.
I did look up more on the forums and find that people generally plug a power conditioner into one of the dedicated outlets to connect their digital sources. But they connect the amplifiers directly into the wall outlets. Are you not bothered by the power surge?
Milpai,I am using one dedicated line with my PS P10 power conditioner that has just my digital components plugged into it. That also includes video items.

The 2nd dedicated line is for my Pass Labs Amp. And the 3rd is for my 3 JL Audio F-113 subs.
My outlets are all the Furutech GTX Rhodium and the outlet frames/covers are the Oyaide. (I think they look better than the Furutech).

I used some of the sonex insulation in the ceiling , but I also used regular fiberglass in the ceiling and walls. I installed a exterior steel door frame.

The music is muted outside of my room, but the bass still radiates to the upper floors.
I have read that having a separate ceiling that does not touch the ceiling joist are the way to go to eliminate the bass transfer.

On the question of power surge, I installed a whole house power surge protector in the breaker box.
Ozzy,
Thanks again for letting me know. My contractor also suggests to use fiber glass.
I have decided to go with a single dedicated 20 amp line (10 gauge) with a single outlet (duplex). I will connect my Brickwall into one port and the amp into another. Will do a comparison and then finalize. I plan to go with either the Furutech GTX or the Oyaide.
I am looking to go with Cullen Cables Crossover Series for my amp, since I would need a longer power cord for the amp.
Any other power cord suggestions in the same price range?

I have read tons of stuff on outlets. So I have decided to go with 2 Porter Ports - one for my living room video and other for my basement video.
I have decided to go with whole house surge protection. This is for the rare case when surge comes to your lines externally. But it looks like most of the surges happen because of internal components like start-stop of machines, equipments, etc. But since dedicated line will not have other equipments hooked up to it, I am thinking that the surge that my audio equipment faces, are all external. Hence the whole house surge protection. What do folks on this forum think?

Does whole house surge protection have negative impact on amplifier performance?
I built a basement listening room with similar dimensions to yours in a previous home, following a Rives Audio design. The walls were built with staggered studs, where the outside was on one row of studs and the inside was on a different row of studs. The inner wall was two layers of sheet rock of different thickness separated by a layer of Green Glue. Rives didn't specify stuffing the walls. Since the room was under my wife's office, I stuffed the cavities between the joists with UltraTouch insulation. The ceiling was two layers of sheet rock with Green Glue. Rives specified a solid door for the room, and I added gaskets around the edge of the door jamb and a sweep on the bottom of the door. Rives' design also included soffits down the long dimension of the room stuffed with fiberglass, triangular bass traps in the front corners, and half round bass traps on the long wall at 1/3 and 2/3 of the length. The front wall was convex, made of masonite bent into a gentle curve. The space behind the masonite was stuffed with fiberglass. The design called for a row of Ikea Billy bookshelves across the back wall, for CD and LP storage. The bookshelves were set at a slight angle to the wall; if you looked down on the shelves they looked something like the teeth of a saw. The shelves made the entire back wall of the room into a giant diffusor. Lastly, Rives' design had four acoustic devices providing absorption and diffusion suspended from the ceiling over the middle of the room, above and in front of the listening position. These were made from 1' x 6' boards. A 2" thick layer of Roxul rock wool, covered in cloth, was glued to the upper surface of the boards. The boards hung at an angle with the rear edge higher than the front. My electrician put the room on a separate subpanel from the rest of the house, and it had five dedicated AC lines with hospital grade outlets. It was by far the best sounding room I've ever had. We weren't going for a sound - proof room but it was exceptionally quiet, and no one in my family ever complained about the sound leaking out, even when I played my system very loud.