Anyone renovated a basement listening room recently? Advice on basic materials

I don't think I'd ever choose studs + sheet rock for a listening room unless forced to (such as today, given that's the kind of construction in my house).

No chance of doing solid walls?

Ah, exactly: Could you clarify what you mean by solid wall? The current walls are the cement foundation, so we need to put a vapor barrier + some form of insulation up against the cement.  Many thanks

Your main priority will be the damp proofing of walls and floor, and presumably you will be using a proprietary system for this. I can’t imagine there is any alternative to sheetrock on top of that. If soundproofing the rooms above is needed, consider using acoustic sheetrock on the ceiling. 

A dedicated mains electrical supply would be worth putting in while you’re at it, and a network cable if you use a streamer or any computer audio. 

ChrisSU posted:

I can’t imagine there is any alternative to sheetrock on top of that.

Wood paneling for one (on the walls).

ChrisSU posted:

If soundproofing the rooms above is needed, consider using acoustic sheetrock on the ceiling. 

Also a drop ceiling with acoustic tiles, very common in US basements. It offers the advantage of easy access for lighting, wiring and HVAC modifications, and is less sonically reflective than acoustic sheetrock.

mutterback posted:

Ah, exactly: Could you clarify what you mean by solid wall? The current walls are the cement foundation, so we need to put a vapor barrier + some form of insulation up against the cement.  Many thanks

Missed the comment about foundation, but it seems like it's a great scenario for building a room inside a room.

As for sheetrock, just stick to the heaviest stuff you can find (5/8", double or triple up in the ceilings, etc).

Double board the ceiling, preferably with insulation between to attempt to prevent sound travelling upstairs.
Wall insulation is also a good idea after the vapour barrier  - those concrete walls are cold. 
In my basement "cinema" room, I have the walls covered in a padded material which makes the sound almost like being in an anechoic chamber. 

I once soundproofed a friend’s basement using a proprietary system of acoustic plasterboard (aka sheetrock) with fixings designed to decouple it and reduce transmissions. As per the manufacturers instructions, the key was to provide a complete seal, and I find it hard to imagine this could be achieved with removable tiles. In this case, the end result was not 100% successful, but then, he was a drummer and used the basement to practice! 

I am building a room in my new house, the important essentials are;

1.0 Dimensions. There are ideal dimensions in terms of the room itself, 

There is quite a bit of information about the appropriate dimensions on the net of course. This seems to be very important, square rooms do not make for good results.

2.0 Strength or "heft" to the structure, as well as lack of resonating materials. It all should be stuck together well and fixed together.  This goes to such things as properly braced stud walls, and ensuring that any light material is well braced. Be careful about the connections to the main building strong and heavy/large can also result in good transmission of bass frequencies - just what you do not want.

3.0 Sound "proofing". The most effective means is to have a separate structure for the room. A room that is not attached to the main structure. A room within a room so to speak. This room needs to be sealed "airtight" as mentioned in the previous post. As mentioned there are proprietary systems but the best is to just construct "a room within a room." 

4.0 The treatment of the room itself - appropriate reflection and absorption. The most up to date advice is to have the room "as dead as possible" More absorption than reflection. This can be an extremely large undertaking itself, and many $$ can be spent.  My experience is to have it "cosy." Carpet on the floor and adequate absorptive material at the first reflection points from the tweeters to the listening position. Lots of pictures and other things to help break up reflections. A bit of experimentation with rugs works well.

The advice of two layers of plaster is good advice. If you cannot build/afford the two walls method then a single wall that is made from two layers of plasterboard over the studs and the cavity well insulated with an appropriate proprietary sound absorbent material is a good compromise. I have often done soundproof offices with this method and it works well and is economical.

Good luck. The subject is a minefield. There are products that claim marvelous results, and the old maxim of if it sounds too good to be true then it probably is, is good advice.

Hi MutterBack 

There is a solution available that reduces mechanical coupling of sound transfer. It is called the GenieClip system. Affordable and very easy to install. I would suggest using acoustic plasterboard which is fibre reinforced and much denser than standard boards. Use acoustic mastic around the edges to reduce flanking transmission. Google 'ikoustic' for more information on acoustic solutions.

ATB Minh

Moderated Post:  Link removed.  Please don't post unauthorised commercial links in the Hifi Corner, thanks.

When I renovated my listening room, I wanted to reduce any ceiling resonance and also limit the amount of sound that escaped. My solution was 2 layers of acoustic plasterboard, separated by a layer of 'Green Glue' acoustic sealant. Overlap the plasterboard sheets so that none of the joints line up, and skim with plaster to finish. All my walls are solid block work, so wet plastered these. A picture below of the second layer going up with the sealant. Green Glue sets to the consistancy of warm bubble gum, so absorbs vibrations really well.

Thanks - I've been looking at Green Glue. How did it turn out?

As Listener72 noted, the room dimensions are critical. Proper design here can negate potential problems arising from standing waves, etc.  Of course dedicated mains are always recommended, The nice thing about building on basement slab is you'll be able to couple your equipment rack and speakers without having to concern yourself with floor bounce and resonance.  There are also some inexpensive absorber and diffusor tiles that can easily be placed. 

As far as carpeting goes, a natural fiber carpet (wool, cotton) has much better acoustic properties than synthetic types.  Sounds weird, but here's how to prove that to yourself:  find every bath towel in your house (they are nearly always 100% cotton.   Listen to some of your favorite music, then lay the towels on the floor between your listening position and the speakers.  The more area you can cover the better. also over a tv is there is one on your listening room.  Listen to the same music again.  The difference is noticeable.

Have fun!

mutterback posted:

Thanks - I've been looking at Green Glue. How did it turn out?

It works well in my experience. I would use it in any stud work construction where you want to eliminate any rattles, or where materials are in layers.