[Barry.B]

Hi All,

I'm in the position where we are drawing up detailed planning for the house we want to build on the plot of land we have recently purchased.  Hopefully we will be able to include a listening/music room in the basement if funds run that far.

I was looking for advice on ideal room size, also the minimum size you can go to without compromising the sound and tips for setting it up please.  This is a one off opportunity and I want to get it right first time round.

We are in the UK and it's not a massive plot (40 x 100 feet) so we are trying to make best use of the land, hence the possible basement

My system consists of : -

Meridian G08 CDP
Bryston BP25 DA
Lexicon 212 NT power amps (rebadged Bryston 3BST's)
Vertically biamped PMC LB1's
Chord Chorus and Pro dac interconnects and Odyssey speaker cables

Many thanks,

Barry.B

[bpape]

Ceiling height is ALWAYS a bonus if you can get it.  Shoot for 3 meters if you can - or more!

As for room size, that's kind of tricky.  I wish I had just a little more but it's really pretty nice for 2 channel - approx 5.5 meters x 7 meters. 

Bryan

[warnerwh]

What you want to make sure of is that you don't have two dimensions that are the same or a multiple of another dimension. In other words a 4m dimension means you don't want a 6m or 8m or 12m etc. dimension. This will cause the room modes to be far worse than would be normal.

Also put in your budget room treatment. When I built this room in my basement I figured I'd do it right. The last house had some but this room is LEDE with four large bass traps. It's waaayyy worth your money and really doesn't cost much. You'll be amazed how much better your system sounds.

When I put my system in my new room I'd been astonished for days. Same equipment but superior acoustics is why. Even now my room has the best sound I've ever heard and the room treatments are a major reason why.

If you build in a basement you may want to consider using a double thickness of sheetrock with some resilient channel in between them to isolate the sound in your listening room better from the rest of your house. Making a double thick ceiling won't cost very much at all. This had also been a good investment. Resilient channel costs very little as does the bit of extra sheetrock.  If you use resilient channel make sure it's put up asymmetrically to vary resonance frequencies.

You'll be very happy with a dedicated room.  It's so nice to have a quiet isolated room to listen to music in. 

[JLM]

You're heading right down the path I travelled recently.  My goal was to keep cost down (important when you build).  Thanks to my builder  I didn't quite get everything I wanted in the room.  If you're going to finish the basement anyway, the space is "free" and the additional expense minimumal (in my case about $200).  The primary advantage is privacy (man-cave stuff).  The goals for the listening room is two-fold, for the room to "sound" good and to be acoustically isolated from the rest of the house.



1st step is to size the room (so that it will "sound" good). 

Keep room proportions in ratios like 1 x 1.62 x 2.62 to minimize standing waves.  This is the ratio I followed to arrive at an 8 ft x 13 ft x 21 ft room.  This is the classic greek architectural proportions but a couple of smaller ones exist too.  Bigger is always better as it will help minimize room reflections.  Ceiling height will probably be your limiting factor.  Account for reduced height for a drop ceiling.


2nd step is to pick room materials/construction (so that it is isolated).

Use an acoustical drop ceiling.  This is the "mistake" I made with the builder.  I specified gauge metal "Z" channels to suspend the drywall ceiling.  He refused and screwed the drywall directly to the ceiling.  Now I hear the washing machine, dryer, footfalls, etc. on the floor above even though the ceiling had fiberglass batts added.  So my advice is to simply install the drop ceiling.  This will be about half the extra cost to make it a "listening" room.  (Hint, don't use recessed light fixtures on the ceiling as I find that they sound to transmit too.)  And try adding insulation on across the top of the acousticall pads.

Build the interior walls using staggered stud construction.  In the U.S. we'd start with 2x6 top and bottom plates, then 2x4 vertical studs.  One set of studs aligns along each edge of the plates and they're staggered so that the studs from one side doesn't touch those on the other.  Then add fiberglass batts.  This makes for a very effective sound isolation barrier.  This shouldn't cost more than $100 extra.

Use a weather sealed insulated fiberglass door.  They come with a wood grain and can be stained or painted to be quite presentable.  Depending on the quality of the doors in the rest of the house this could be a cost savings.

Use flexible insulated ductwork to serve the room.  It's cheap and easy to use, but reduces air flow substantially (so don't let the builder use it elsewhere). 

Wire separate circuits to serve just the listening room and locate them at the top of the circuit breaker box.  In the U.S. houses are wired in either 14 gauge for 15 amp circuits or 12 gauge for 20 amp circuits.  Go with the heaviest possible.  I went ahead and used cryogenically treated 20 amp hospital grade receptacles (three cost $100).

Room finishes are up to you, just figure on proper room treatments afterwards (season to taste).



The effect is (except for the ceiling transmitted sounds) an eerily isolated feeling that took some time to get used to.  In fact there are times I still leave the door open.  Weird to walk out of the room and realize that the furnace which is only 10 ft away, is running.  The room is warm (all the insulation and the basement itself is already well insulated).  The privacy, the ability to listen at lower levels due to reduced background noise, and the ability to listen when I want are all wonderful.

[MaxCast]

Great post, JLM.

[Rocket_Ronny]

JLM's ratios are great in my books. 

If you are really serious about audio then go no smaller than 16' by 26' with a sloped, off center ceiling if possible of 10' high. If you can squeek out a 18' width even better. The room size of sooooo important and yet almost everyone seems to miss it. Instead they worry about which power cord to use. 

Then try your speakers 12-14' off the back wall and about 12' apart, sitting about 9' feet in front of the speakers. This gives a fabulous soundstage that most guys can't even dream of. 

Rocket_opinionated_Ronny

[Barry.B]

Hi All,

Many thanks for the replies so far (the more the merrier), they give me much to consider and are very much appreciated.  I wasn't expecting to get room sizes of 18 x 26 feet suggested, but you live and learn.  This may mean a little "negotiation" with my other half!!! but I want the house to be right for her as well or it's not worth doing at all.

Regards,

Barry.B

[WEEZ]

A few ratios considered to be the top (5) according to M.M. Louden:

1) 1.9 times ceiling height by 1.4 times ceiling height
2) 1.9            "                    1.3           "
3) 1.5            "                    2.1           "
4) 1.5            "                    2.2           "
5) 1.2            "                    1.5           "

As previously mentioned, the Cardas 'Golden Ratio' works well also.

WEEZ

[Daygloworange]

JLM,

With all the attention to detail you've done, that room should be a great place for audio. Low noise floor, proper room dimensions. Cool.

Is the room finished? Are you already set up in there? What room treatments/finishes have you done to the floors and walls?

I'm envious BTW, can you tell?

Cheers

[JLM]

Barry,

Bigger is better, but whatever you do, don't give up on the primary concept of having your own, dedicated, private, man-cave room. 


Dayglow,

The room has been "done" for a year (are audiophiles ever really done?).  Ceiling and walls are painted drywall, the floor is padded carpet over concrete.  No windows, but there is a 30 inch by 50 inch protrusion in the back left corner (needed to access mechanicals through the adjacent storage room).  As I posted, it took very little money, just forethought.

The speaker/listening chair are set up in the Cardias recommended nearfield position with speakers 66 inches from the front wall and 45 inches from side walls.  Speakers and chair form a 68 inch equalateral triangle.  Side walls have a total of 3 tall bookshelves and the back of the room includes a large fake plant, drafting table, open desk, two drawer metal file cabinet, office chair, and the door.  My previous room was shared, but similarly sized with two openings into other spaces and a picture window.  Initially this room sounded similar, but not as good as that room as the room was set up opposite to the recommnded LEDE (live end/dead end) method with bare walls around the audio end of the room. 

So last summer I added six GIK 244 high density 2 ft x 4 ft absorption panels that helped.  Four of the panels are stacked into the front corners (floor to ceiling) for maximum bass effectiveness with the other two on either side wall at first reflection points (which widens the soundstage).  I'd like to try adding about 50 square feet of DIY diffusion to the front and side walls and move those last two GIK panels into corners, then play with digital EQ to flatten out the room/speaker frequency response.  Maybe then the room will be done. 

With my single driver speakers even young listeners get "big eyes" as soon as they sit in "the" chair.  Suddenly (with the right recordings) imaging and soundstaging become clear.  It's halfway between "normal" listening to speakers and using headphones.  Very cool.

[Big Red Machine]

Ah, mancave!!  Can't seem to keep the wife out of mine.  She loves the sound.  Guess I should not have let her help with the decorating.

Here's my mancave story:

http://av123forum.com/showthread.php?s=&threadid=14094

Enjoy your room.

[MaxCast]

Ah, mancave!!  Can't seem to keep the wife out of mine.  She loves the sound.  Guess I should not have let her help with the decorating.

Here's my mancave story:

http://av123forum.com/showthread.php?s=&threadid=14094

Enjoy your room.

How'd those frequency sweeps turn out?
Great write up!

[PhilNYC]

Here are a couple of links describing the Cardas "Golden Cuboid" and "Golden Trapagon" ratios for the room:

http://www.cardas.com/content.php?area=insights&content_id=29&pagestring=Room+Setup+4

http://www.cardas.com/content.php?area=insights&content_id=36&pagestring=Room+Setup+10

[Rocket_Ronny]

Barry:

As a good compromise you can make your audio room a mix of the living room and dining room joined together if a seperate room is too much.

That is what I have had for many years. Everyone co-habitates.

Cardas Golden rule, bah!!!  While it may be great don't get stuck with rules. If you want a puny soundstage then go for it. But if you want a sound stage to BLOW YOUR MIND then do the 12' off the wall thing. It is a breath taking experience.

If you want to know what I am talking about check out my old room at http://www.scripturesongs.com/audio.htm   I went to a lot of work to build a dedicated room for audio. It was 16' by 13'. It destroyed my audio interest. The big room just kills the smaller.

Rocket_Ronny

[Ethan Winer]

Folks,

Just to clarify one point made earlier:

Keep room proportions in ratios like 1 x 1.62 x 2.62 to minimize standing waves.

Some ratios are certainly better than others, but all domestic size rooms have "standing waves," and peaks and nulls, and modal ringing. The only benefit of choosing one of the preferred ratios is the resonant frequencies are more evenly spaced. An even spacing between modes reduces the number of multiple modes, where two or more are at similar frequencies, which makes their effect even worse than for one mode. But no matter what ratio or shape you have, there are still modes and those modes need to be treated with bass traps.

--Ethan

[TjMV3]

My room is ....  18'  9 1/2 " X 15' X  9'  6 1/2" ( Ceiling ).

If anyone has any ideas how to make this room work,  let know

I'm guessing bass traps in all four corners,  diffussers along both sidewalls.......nice thick curtains?

[Daygloworange]

JLM,

The room has been "done" for a year (are audiophiles ever really done?). 

No. It's a disease. 

So last summer I added six GIK 244 high density 2 ft x 4 ft absorption panels that helped.  Four of the panels are stacked into the front corners (floor to ceiling) for maximum bass effectiveness with the other two on either side wall at first reflection points (which widens the soundstage).  I'd like to try adding about 50 square feet of DIY diffusion to the front and side walls and move those last two GIK panels into corners, then play with digital EQ to flatten out the room/speaker frequency response.  Maybe then the room will be done. 

With my single driver speakers even young listeners get "big eyes" as soon as they sit in "the" chair.  Suddenly (with the right recordings) imaging and soundstaging become clear.  It's halfway between "normal" listening to speakers and using headphones.  Very cool.

I'm sure it sounds excellent. Very cool. I've been experimenting with diffusion lately, and very pleased with the results. My bass traps are old corner bass traps (not foam). Small and not the most effective. It's the area I want to focus on next in room acoustics. And yes ,my system requirements are going up the evolutionary scale as a result.......

Cheers

[Ethan Winer]

My room is ....  18'  9 1/2 " X 15' X  9'  6 1/2" ( Ceiling ).

If anyone has any ideas how to make this room work,  let know

I'm guessing bass traps in all four corners,  diffussers along both sidewalls.......nice thick curtains?

Bass traps in the four wall-wall corners is the minimum. For even better results you should consider treating the wall-ceiling corners too - assuming you can stomach the look.

As for diffusors on the sides, it depends on how wide your room is. Narrow rooms, where your ears are close to the walls, often do better with absorption there.

--Ethan

[JLM]

Thanks for the clarification Ethan, I often state it this way but know better. 

Cubic or square rooms are the worst as the standing waves occur at the same frequency in two or three directions and so become additive.


TjMV3,

There are a couple of "classic" room treatment approaches:

LEDE (Live End, Dead End) in which the half of the room that contains the speaker is made as absorptive/diffused as possible (walls, floor, and ceiling).

Another method is similar but treatments are applied to opposite surfaces (floor, not celing; front wall, not back wall; left wall, not right wall).

Perhaps the most effective method is to absorb/trap bass in the corners and absorb/diffuse first reflection points (closer ones should be your highest priority).

[Ethan Winer]

I often state it this way but know better.

I figured you knew that, but I wanted to clarify for others. I see people all the time express the (wrong) belief that a "perfect shaped" room has no bass issues. Worse, many times I've seen people build a room where the corners are cut off with a sheet rock wall in the mistaken belief that will avoid the need for traps. In truth, all that does is remove the very best places to put traps.

--Ethan