[es347]

We are building a new house with a full basement with 9 ft. ceilings.  I have space set aside for a listening room.  The room will also house my guitars, amps, recording stuff also but I want one end to serve as a high quality environment for 2 CH audio.  The room can be about 16 feet in width and as deep as 20 ft. +/-.  I would love to hear anyone's suggestions on what to do and not do....floor/wall coverings, type of ceiling, etc.  No Michael Green paraphenalia please.

thx. in advance.

[kfr01]

es:

I went with 12"x12" home depot acoustic tiles for the ceiling in mine.  It doesn't look quite as good as painted drywall, but it sure helped with the acoustics.  We used 5/8" drywall.  Other than some dedicated 20amp lines coming to the room, I didn't do anything else special.  Carpet for the floor.  I plan to use GIK panels to clean up the rest.

Good luck! 

[ctviggen]

Who's Michael Green?  What do you want to accomplish when you build your room?  If you're looking to prevent other people from hearing you, think double walls with insulation. You can do the same with a ceiling.  Also, a nice, well sealed door will keep sound under control (there are also nice sound-transferral-reducing doors, but these can get a bit pricey).  Personally, I'd build double walls, double ceiling, and put in tons of connections everywhere for the invevitable HT system.

[Russell Dawkins]

I had a similar size space available in my basement and turned it into a very respectable sounding room by the relatively simple expedient of
1. putting a false wall in the speaker end and incorporating a large (4 foot by 12 foot) wide range trap centered behind the speakers, and
2. building the side walls with a 14 foot radius curve (bulging inwards). This was accomplished with curved plywood plates nailed to the cement floor upon which were tacked 2X4 studs to which were screwed sheets of 5/16th inch tempered hardboard. Stiffening shelves were incorporated floor to ceiling of 3/4" plywood. about 10 inches deep with a vertical spacing of about 12", tapering in size and spacing toward the ceiling.

By the way it sounded even better before I had the double thickness gyproc ceiling panels on suspension attachments installed, and if I were to do it again I might go for acoustic tiles on the ceiling and forgo the misguided attempt to isolate from the room above. I say misguided, because the ceiling light pots go through the gyproc and spoil the intended result.

The result sounds great and has a notable lack of bass nodes, such that bass sounds very much the same over most of the room, and the R time for the bass is much shorter than the average room of its size with conventional construction. If you hit pause on a CD in the middle of a bass-heavy passage, the speed at which the bass tone stops is obviously quicker than what I am used to, and this contributes to articulation in the bass.

It so happens that the front 2/3 of the room is symmetrical and the rear 1/3 is irregular but reflective, i.e. diffusive.

This is my mastering studio set up and it works very well and didn't cost an arm and a leg. I didn't have to consult with Michael Green, either.

[es347]

Hi to all,

Thanks for the responses.  I have things to think about not the least of which is how to convince my wife to install acoustic tiles on the ceiling (low WAF I fear).  Russell, you have done some pretty extraordinary stuff with your space.  I need to think about just how much I want to do.  ctviggen...Michael Green is the Fabio look-alike who sells cute little pillows called "room tunes".  I'm just not into that slumber party look for my listening room I guess.  Thanks again everyone.

es347

[Wayner]

I sounds like you have the opportunity to construct your room using the Golden Rule. This rule is a ratio: .6:1:1.6. If you have a 9' ceiling, the ideal dimensions for your room would be 15' X 24'. The golden rule is used by acoustic designers as the shape helps to cancel standing waves. Another aid is to construct an equallateral triangle in the ceiling corners as this is a natural horn. the leg of the triangle should be at least 16 inches long. The next important thing is building the room symetrical. you don't like having your balance control scewed off to one side, so don't make funny in's and out's in your room. Speaker placement should be in absoute symetrical position. In other words, drawing a center line in the room and make the positioning of the left hand speakers mirror image to the right hand speakers. Position them to within a 1/4" of each other. Carpet on the floor, sprayed ceilings, and sheetrock walls are all o.k. if you have nice sound absorbing furniture, which should also be place symetrically within the room. One wall, like the back wall could be covered with wood. The room will sound grate. Definitly run dedicated power lines (20 amp), (maybe 2) to the location of the equipment rack. Also bring several runs of coax, telephone and cat5 wire to this location. of course, wire in surround speakers. Use hospital grade 20 amp outlets for your dedicated power as well. Good luck, it sounds fun!

[andyr]

I sounds like you have the opportunity to construct your room using the Golden Rule. This rule is a ratio: .6:1:1.6. If you have a 9' ceiling, the ideal dimensions for your room would be 15' X 24'. The golden rule is used by acoustic designers as the shape helps to cancel standing waves.

Wayner is correct in quoting the "Golden Ratio" as producing the basis for a good-sounding room but needs correcting on 2 small points:

1.  The ratio is actually 0.618 : 1 : 1.618 ....  Another way of exprssing this is 1 : 1.618 : 2.618 ....

2.  The golden ratio certainly gives you an accoustically-good room but there is quite a spectrum of dimension possibilities that give you just about as good - so, es347, don't stress about getting exact dimensions to match the 9' ceilings.  If you want to PM me your email address, I can send you an Excel spreadsheet originally produced by THX which allows you to play with room dimensions and see what (bad) nodes it has.  Start with 9' / 14.6' / 23.6' , see what the nodes are and then play with perhaps more "acceptable" dimensions (given you can't go deeper than about 20') and compare the node patterns.  (Better still, if I could permanently post this spreadsheet on AudioCircle so that everyone could access it ... heeelp, Mr Moderator!!     )

Regards,

Andy

[Frihed91]

I have seen a nice design for ceilings.  Every 3-4 feet run 2x4 (flat) (2x2 might work) across the ceiling width, with about 4-6" clearing to the real ceiling.  They have to be hung to keep them parallel.  When that is done, you cover these with heavier fabric.  Then you run the same type fabric up behind the 2X4s the length of the room - a lot of sewing.  Then you let it billow down a few inches (whatever looks best) between the 2x4s, so it looks "Arabian".  I have seen this done in professional stdioes and music halls.

As far as walls are concerned: don't make them hard and again put moveable curtains on the reflection points.

Carpet the floors in front of the speakers.

Now look at my room from hell.  Sloped walls.  Brick chimneys.  Brick walls on one side.  About 60 feet long and 15 feet wide.  I have 0 treatments.  As you can see from the lttle stool, i listen very close, right in front of the stage!

[fajimr]

es

have you wandered over to the acoustics circle?  lots of ideas there- and ethan (real traps) and glenn (GIK) often share their insights.  ethan winer has a great primer on his site (http://www.ethanwiner.com/acoustics.html)- this is by far the best advice I could give

[JLM]

Here's a few things I did for my dedicated listening room (in the basement):

Followed the golden ratio (8 ft x 13 ft x 21 ft).

Built insulated modified staggered stud walls.

Used an exterior insulated fiberglass door with weatherseals.

Used flexible/insulated supply air duct to the room.

Ran 3 dedicated 20 amp circuits each to a cryo'd hospital grade Hubbell receptacle and put all on a separate ground.

Total additional tweaking cost was about $200.


The room leaks to the kitchen/mud rooms above due to drywall ceiling and 6 recessed light cans.  As mentioned above, had I to do it over again I would have simply put in a suspended ceiling with acoustical panels.

[JohninCR]

es347,

IMHO the 2 most cost effective things to take into account if you have the opportunity to construct a room from scratch and have dimensional flexibility are: 1. As previously mentioned, use the golden rule for your room dimensions, which minimizes the impact of room modes  2.  Construct your walls so they are panel bass traps tuned to a wide range of frequencies.  Then for a fully treated listening room all you have to play around with are absorption and/or diffusion.  In addition, if you need sound isolation, especially necessary if your room will double as an HT now or later or you just like to crank the volume on occasion without disturbing others, a double wall construction can be done very cheaply during the construction phase.

[Bach]

A book I would recommend is Sound Studio Construction on a Budget, by F. Alton Everest. It covers modes in listening rooms etc, but it also has nicely detailed chapters on wall and ceiling performance (including STC ratings for many types), silencing HVAC systems, and sound absorbing/diffusing materials and structures. Until I read this book, for instance, I never new about resilient hangers for sheetrock ceilings, or the use of resilient metal channels for drywall.

I’m still deciding myself on what to do for my own basement studio/listening room. I can say I learned much from this book.

Of course, if you really want to isolate this room from the rest of the house the best you can, the way to do it is to build a room within the room (I would, but don’t have the ceiling height to spare). This would leave some amount of space between the interior walls and exterior basement walls, as well as between ceiling and the floor. By doing this the right way, you can severely limit vibrations through the walls and between ceiling/floor juncture. Have fun.

[srlaudio]

We have found that 4 inch thick bonded cotton in 2 ft square standard ceiling grid way outperforms standard ceiling tiles.  The subfloor of the above room should be assembled to "Float" on the floor joists.  Green glue or equivalent.  There is enough ceiling height to use a floating raised floor with built in wire troughs.  We would use surface treatment on the walls composed of large diffussor panels, matching absorption panels, and floor to ceiling corner bass traps.  I know about Michael Greene......what is he doing now? selling light bulbs?

[Double Ugly]

I know about Michael Greene......what is he doing now? selling light bulbs?

Now *THAT'S* funny! 

[Russell Dawkins]

I think things are slowing down a little with Mr Green.

Here's his site: http://www.michaelgreenaudio.com/forum/

[JLM]

The last time I saw him around he was ready to sue a few of us for slandering him.  He kept preaching about something called "tuning", which I couldn't make out what he was talking about, but for examples of loosening covers/parts within components and speakers designed for the cabinets to resonant.  IMO very quacky.  (Oops, hope he doesn't see this post.    :roll:)

[nathanm]

Michael Green caused the Great Threaded Rod and Nut Famine of aught five.  Grim times it was...

[tvyankee]

hello

I don't know if this will help but their is a good artical in Electronic House with Jim Thiel from Theil Audio that talks about building a room just for sound.Its on page 43.


Good Luck

[JLM]

Like seemingly everything in audio, the law of dimishing returns kicks in with listening rooms too.

Given that the space is available, the biggest bang for the buck comes quickly.  Use of basement spaces that don't have a window is ideal and normally the least desirable place in the house.  Insulated double or staggered stud walls, use of insulated drop ceiling, and insulated/weather sealed exterior door are all relatively cheap (in most cases less than $500 total).  Shaping the room using the 1 x 1.6 x 2.6 proportions, substituting insulated flex duct for aluminum, and putting the room on it's own circuit usually cost nothing. 


IMO the advantages of having a dedicated listening room (in order) are:

1. It provides a "get away" place.
2. You can listen when you want at the volume you want and to what you want.
3. Sound isolation from/to the room from the rest of the house.
4. No body is messing with your stuff.
5. You can tweak as needed, without WAF issues, to get good sound.


I don't recommend built in treatments because:

1. For better or worse, you're pretty well stuck with them.
2. You can't take them with you.
3. You're starting with a non-standard room that would be hard to get advice for.
4. Could get expensive as you'd be taking up more space and possible building a third set of walls.
5. Such a room can get "weird" and ill-suited for other uses or resale.