Please explain to me what the different parameters of speaker placement do

Whew.. some title .

Seriously, could anyone put down in a few words what exactly does each of the variables in the placement of speakers do for the sound?

Off the top of my head (there might be more, or I might be inventing some):

- speaker to speaker distance
- toe-in (inwards angle- is there such a thing as toe-out? Seriously)
- front-to-back placement
- height, I guess (for stands- I have mine on the floor)

I'd appreciate any answers, comments, etc., since I'm in a bit of a struggle with my system of late and would like to untangle things as much as possible so I can make the best of it.

Thanks!

 

Damián, what speakers are you using? This can make a huge difference in placement. With my Castles I noticed a large improvment using this room set-up suggestion. Everything became more focused with a new added staging.

 

Sony SS-U4033. They're very much crap from what I can tell, but I can't replace them for the time being ($$$). Wish I'd known better when I got them.

Here's a link where you'll ind some info on them:

http://www.audioreview.com/Main%20Speaker/Sony/PRD_120611_1594crx.aspx

 

They seem like the sort of speaker that would benefit from the Cardas placement. You might lose bass reinforcement pulling them well into the room, but you should gain imaging with a more near-field listening position, well away from the sidewalls.

What are the dimensions of your room? Are you free to place them anywhere?

 

My little synopsis would go like this:

speaker to speaker distance = imaging
toe-in = imaging
front to back placement = bass reinforcement
height = high frequency focus

I'm probably off in the accuracy department here but I gave it my best shot.

 

Mikek: Thanks a lot.

Hi Geoff. Thanks for chiming in.

The speakers are currently set according to something called the 'eighths rule' or maybe it was the 'sixths rule' (I was told about it on the Speaker Asylum).

They're rather close to the walls, specially the back wall. I'm not sure I could bring them into the room too much without my family complaining , though.

The Cardas method I believe I read about once, but iirc I couldn't quite wrap my head around it or found it impractical for some reason.

I don't have the dimensions handy (I have them jotted down somewhere, I'll try to find them), but it's a rather large room, rectangular, with a bow window on one of the short sides. The other short side is open (no wall), as this is one half of a dining room/family room space. Walls and ceiling are plaster, floor is hardboard. Ceiling is rather high.

The room is laid out with the couch (my listening spot) along one of the long walls, with the speakers facing the couch. There's a fireplace opposite the couch too, which means there's an area surrounding it that I can't use (not because of heat, but because of the way the fireplace is laid out).

It's always seemed like a far-from-ideal room to me. Between the bow window, the non-wall on one side, the hardwood floor, naked plaster walls and high ceiling it's probably an acoustical nightmare.

 

For years now I have used the Chesky Jazz Sampler and Audiophile Test CD (Chesky JD37) to do all of my speaker setups. It's an amazing test CD that I can't live without. I'm sure it would aid you in doing whatever speaker placement tests you wish.

The music on it is excellent too, especially "Viola Fora De Moda".

 

From what I've gathered:

Speaker to speaker distance affects the width of the image. A wider spread will give you a wider soundstage (more stereo separation), but too wide and you hear a hole in the middle.

Toe-in affects the focus. Normal speakers (individual cones) tend to "beam" or narrow as frequencies get higher, so usually when you toe speakers in, you'll hear more highs and things get clearer - but if your speakers are too bright, they'll sound brighter too. Toe-in probably makes more difference the closer you are to your speakers or the wider they are separated.

Front-to-back placement affects how much bass reinforcement you'll get from the sound reflecting off the rear wall. Distance from side walls will affect this too. Some speakers are designed to be against the rear wall. Klipschorns are designed to be placed in the corners. Many speakers are designed to be placed away from walls.

Speaker height affects the balance of the sound you hear. Because tweeters "beam" the most, placing the tweeter at ear level will give you more of what they're producing. You can also tilt the speaker to aim the tweeter at listening height.

There are calculations that plot positions to minimize resonant frequencies depending on your room dimensions, but they usually involve using computer software. But you can start with the Cardas recommendations and play around. Speaker positioning is a hobby unto itself.

 

Cwon did a great synopsis - I would just add:

-speaker to speaker distance also influences how close the speakers are to the side walls and that impacts the room's affect on the sound. Along with center fill this distance also affects apparant soundstage at the edges of the field.

-toe-in also affects center fill and the "air around the center insruments/voices.

-front to back distance affects distance from the front wall, but in shorter rooms, it also affects distance from listener to back wall. Together these have the biggest affect on tonality and soundstage. You can create an artificial soundstage that was not on the recording by placing speakers too far from the wall at the expense of accurate tonality.

-speaker height also affects the volume of the soundstage

In general, you want to observe the following:
Do not place anything large or reflective between the speakers or between the speakers and the listener. Start with the speakers 2-3 feet from the wall and 7-9 feet apart, toed in slightly. Set the speakers height so the tweeter is a bit above the listener's ears. Set your listening chair at least 6 feet from the rear wall and at least as far away from the speakers as they are from each other. Put absorption or diffusing material at the reflection points along the side walls and possibly behind the speakers and over any windows.

Damian, to make your system work better you will need to move it so the open wall is behind the listener. Do not be afraid to make big changes to see what happens to the sound. When you get close to the right spot you will start to hear changes in 1-2 inch increments. This all takes time, but when you are done the system will start to really sing, the pace will be natural and the sound will "make sense". Have fun!

 

Thanks for the suggestion Randy. I'm afraid I might get kicked out of the house just for proposing such a thing, though .

 

Here are a couple of more speaker placement ideas:

http://www.immediasound.com/Speakersetup.html

http://www.decware.com/paper14.htm

The decware paper is unusual. As you can see, there are a lot of different things you can try. Sometimes rearranging your speakers will change the sound so much it'll be like you got a new pair (for free).

 

Not necessarily. For nearfield listening, some have found best results when the angle formed by the listening position and the speakers is about 72 degrees. Another way to accomplish this is to make the distance from each speaker to the listening position about .86 of the distance between the speakers. I have found that this gives great results in terms of soundstaging and imaging. For one thing, at this position the phantom center channel really pops into focus. Try it!

Also, you can find numerous articles on speaker placement online. A little searching will easily turn up a dozen or so.

 

I have tried nearfield listening, but I believe it does not reproduce as believable a soundstage as sitting farther back. It is a similar in effect to placing the speakers too far out from the wall - the apparant soundstage is spectacular but less involving musically over the long run IMO. I do understand that it may be necessary in a small room however, and if it works for you then that's great. With the right room you can get that center channel to pop into focus without these effects, but it will require a fair amount of work on getting the gear and room to act together in harmony. Without a dedicated listening room it can be difficult.

 

You hit the nail on the head! My family persists in thinking of my listening room as their living room. Plus, living in an open-plan, ranch-style house, there is only one side wall.

 

This is a cool site. Go through the three selections - acoustic perception, rules about positioning and position examples.

http://www.audiophysic.de/info/aufstellung/e_index.html

 

Great! Here's another site to help determine where to place your listening chair to avoid nodes:

http://www.ultimateavmag.com/news/10388/index.html