Speaker Placement

[evilskillit]

This is the only forum I really post to here so I am putting this thread here. Mods if there is a better place for this thread, please move it there. Also I figure it might qualify as DIY since all my gear is DIY.

Anyways, I just cleared out one of the spare bedrooms at our house and turned it into my dedicated music room. I sat everything up and proceeded to listen and the sound was definitely weird. I used a signal generator and identified several nulls from where I was sitting. I figured it was room related and googled "stereo speaker placement" and did quite a bit of reading. Since then I have pulled the speakers out of the corners and that seems to have helped quite a bit.

I was however wondering if anyone here has any brilliant ideas for room layouts. The room is especially annoying to deal with because it has doors in 3 of the 4 corners and tho I am currently blocking two of them I would like to be able to use from time to time.

Anyways, feel free to recommend any layout, I have considered swapping sides putting the speakers on the right and the chair on the left and moving them both closer to the center of the room. I have also considered putting the speakers on the bottom wall and listening in the room short ways instead of long ways. I also considered putting the speakers at a 45" across the upper right corner and listening from the lower left corner. This is my room, currently the wife is not involved in the design, decoration or lay out so feel free to say anything. If you're thinking I should turn the closets into subs, I might, when I have the spare cash...

A picture of the room dimensions and failed layout is attached. I drew it in mspaint for those of you who wanted a cad drawing :cry:

[johnathanwinter]

the first thing i would do with that room would be to remove the doors from the closets. then put up heavy drapes across the area. this makes the closets more usable without the doors ( i removed the doors from my bedroom closet and it made the closet much more usable. anyway once the closet is open id use one to put the gear, on a rolling rack, in to get it out of the way. the curtain could be easily moved when you need to use the equipment. the next thing i would do would be to pull the speakers away from the closets about 2 or 3 foot. the speakers would have a nice backdrop to them with the curtains or drapes behind them. id probably even put a matching drape across the window area with some heavy polyfil on the back side to cut down on the reflections from that little area.

well that would be my starting point. may be a good idea for you maybe not. im sure there are members here that could poke alot of holes in my idea.

the closets and that window area are probably where most of your problems are coming from. I know a closet i have ends up being a bass chamber for some reason, ive been thinking about adding a port to it, LOL.

[evilskillit]

Hrm, the drapes idea could work well, thats what I did with the closet in my daughters bedroom because I hated the side to side sliding bypass doors that were on it.

Couldn't really put my gear in the closets tho because I'm using them for storing some of my tools and extra speaker parts and also because my current speaker cables wouldn't reach that far. I could replace them but for now if I don't have to I would rather leave them be.

[Face]

You could also try moving everything to the long wall without the door or the short wall without the window.

Here's what I use as a guideline for speaker placement. http://www.cardas.com/content.php?ar...ing=Room+Setup

[JonMarsh]

The Cardas guidelines are quite sound, and are based on the the influence of boundary distances, illustrated in this post:

http://www.htguide.com/forum/showpost.php4?p=138262&postcount=2

Golden mean ratios are your friend....

[JonP]

A lot of good suggestions...

I forget the guy in question, but he had a convincing piece on the benefits of a diagonal layout in the room, which apparently can give you a more beneficial reflection pattern. Look at your room from the first, second, third reflection... make a bunch of copies of your scale drawing and draw lines. If you have more ending up on the same side, rather than left speaker bouncing back at you from the right.. you can get better imaging. And you tend to get more on the same side with the diagonal placement. That's his theory.

Closets being bass traps... probably depends on what's inside. Are they stuffed with clothes? Bookshelves, or mostly empty space? I'd guess this could go both ways, you might get some bass trap effect, or you might get two cavity resonators that give you a big peak/null at certain frequencies. Might be better with solid doors closed all the time. OTOH, if you have full control of the room, and the closets are empty, you could fill them floor to celing with rolls of Fiberglass, and they WOULD be real bass traps...

Thing to do, would be get a mic/soundcard setup, and Room EQ Wizard, or other software, and start checking out your room. It would help you with sub placement as well. REW has the benefit of being free... besides being a powerful and easy to use piece of SW. Then you can see what's going on in the room, and how well your changes are working.

And finally, putting some room treatment panels, (Ethan Wiener and other's sites) at strategic points on the walls, will do a lot.

[JonP]

Jon... that's what I was remembering. Wonder if that's available as a calculator, would be a handy thing to have for room placement choices like these. I've seen floor bounce calculators, but no boundary and floor combination ones that would sum 2 or 3.

Is your sheet set up like a calculator, or do you have to do some creative data inputting with measured responses?

[JonMarsh]

That was a MathCAD calculation, based on Roy Allison's work on boundaries, taking into account 3 nearest boundaries. My recollection is that LspCAD can be setup to do something similar.

The most essential point is golden mean ratios for all the distances, to stagger the influences, (1.44 to one) to floor, back wall, nearest side wall. The Cardas technique is quite telling.

Oh, and one last trick that can save a lot of time? Put one of your speakers in the area of where you want to listen, facing the area where you want to place the speakers. Then, go over and listen at proposed speaker locations- or even better, measure with a long gate, or with pinknoise. Find the positions near where you want to place the speakers where you speaker at the listening position sounds best, the smoothest, flattest response, and that's where you should place the speaker to start, maybe with some adjustment to "dial it in". Inverse positioning.


~Jon

[wettou]

Here's what I use as a guideline for speaker placement. http://www.cardas.com/content.php?ar...ing=Room+Setup

Based on this for an 18 feet wide room my speakers sould be 5 feet from the side walls and 8feet from the back wall!!

This mean they are 10 feet away from the front wall??

Makes no sense what so ever

[johnathanwinter]

Based on this for an 18 feet wide room my speakers sould be 5 feet from the side walls and 8feet from the back wall!!

This mean they are 10 feet away from the front wall??

Makes no sense what so ever

if your speakers are 8 foot from the back wall and are 10 foot from the front wall your in a square room this means the from front to back your room is 18 foot and from side to side your room is 18 foot. so your in a square room?

those calculations are for a rectangular room not a square room.

[wettou]

if your speakers are 8 foot from the back wall and are 10 foot from the front wall your in a square room this means the from front to back your room is 18 foot and from side to side your room is 18 foot. so your in a square room? those calculations are for a rectangular room not a square room.

The room is 20 feet long and 18 feet wide which is even worse those calculation suggest the speakers are 12 feet into the room!!! Sure my wife would really like that :lol:

[JonMarsh]

Yes, it's true that the setup that sounds the best has the least WAF. Unfortunate, but true. Try it some time, just to see how your system can sound. If you go to one of those HiFi shows where they have high end stuff, you'll see it setup like that a lot.

Back in the real world, take a look at what the distance is from your woofer to the floor. Now multiply that by 1.414, to get the distance you'll locate it from your back wall. Then take that distance and multiply it by 1.424 to get the distance to the side wall. If that doesn't work because of your room ration, exchange the distances for side and back wall.

[Dennis H]

You could also try it with the golden ratio, 1.618.

[wettou]

You could also try it with the golden ratio, 1.618.

Please explain!

[Dennis H]

I think 1.618 is what Jon meant -- too many things on his mind. The three distances: woofer-floor, woofer-sidewall, woofer-frontwall, should all be different and not be even multiples of each other. a=1.618*b and b=1.618*c accomplishes that.

[evilskillit]

I set up my speakers as sugguested by the cardas web site, sounds good. Now I need to find the best place for my sub. I am now kindof wishing I had made the subs speaker stand height so I could use them as bass bins. Of course I could always just make another set of enclosures. Meh I'll sort it all out eventully, I still seem to have a bit of weakness at 100 and 130hz but its not nearly as dead as it was before.