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Eight Methods of Loudspeaker Positioning

I came across this very useful article on loudspeaker positioning from Audio Art, Taiwan’s leading hifi magazine. The original article is in Chinese and can be found via this link http://audioart.audionet.com.tw/space/8.htm. To share this article with you, the following is my translation attempt.

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“Before we get into the ‘Eight Methods of Loudspeaker Positioning’, let's introduce an important concept, that is that ‘the loudspeakers and the listening space is One’. Sound performance is the product of interaction between the loudspeakers and the listening space. No matter how bad your listening space is, you should be able to ‘find a pair of loudspeakers that are more suitable for that space’, or ‘use a positioning method that is more suitable for that space’ in order to achieve the best result.

How to ‘find a pair of loudspeakers that are more suitable for that space’? This is not the main topic of this article. However, you can follow a few principles – “do not use big loudspeakers in a small room’, ‘do not use small loudspeakers in a big room’, ‘a room with a ‘soft’ acoustic, such as one constructed with lots of wood, should be matched with big loudspeakers’, ‘a room with ‘hard’ acoustic properties should be matched with loudspeakers that have a softer tone’. Add to these the general knowledge that ‘a room that is more fully stuffed with things will possibly sound better; a room that is emptier will possibly sound worse’. If you follow these principles, the sound quality you can achieve even if not perfect should not fall far short.
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Once you achieve an acceptable sound quality, then you have to do loudspeaker positioning. Try the various methods to find one that is most suitable for your system.

1. The 317 Ratio Method

Divide the length of the room by 3. Position the loudspeaker at 1/3 length of the room, the space between the loudspeakers is 0.7 X 2/3 room length.

The loudspeakers should be slightly toed in, but no toe-in is acceptable too. The listening position must be away from wall behind the listener.

This method is suitable for rooms that are bigger and better proportioned (e.g., 1:1.25:1.6 or 1:1.6:2.5). A balanced sound with a wide and deep soundstage can be achieved. This is the method most commonly recommended by Audio Art to our readers.

2. The 331 Ratio Method

Divide the length and width of the room by 3. The loudspeakers are positioned at the intersection points of 1/3 room length and 1/3 room width.

The loudspeakers can be slightly toed in, but no toe-in is acceptable too. The listening position must be away from wall behind the listener.

This method is suitable for rooms that are bigger and better proportioned. Its essence is similar to the 317 Ratio Method, the only difference is that the space between the loudspeakers are narrower. You can also achieve a balanced sound with a wide and deep soundstage with this method. This is the preferred method of the chief editor of TAS.

3. The Screw Hole Method

Position the loudspeakers at a spot between 1/3 room length and 1/2 room length. The loudspeakers should be placed very close to the side walls (unless the room is very wide). Toe in the loudspeakers by more than 45 degrees. The listening position is between 0.5m to 1m behind the intersection point of the loudspeakers’ projection path.

This method is used to cure the problem of sharp highs, thin mids and insufficient lows. It can give excellent results in a lot of bad listening environment. This is Audio Art’s recommendation for the challenging listening space commonly encountered in Taiwan.

4. The Equilateral Triangle Method

The first condition is that the loudspeakers must be placed away from the wall behind them (at least 1m away) and away from the side walls (at least 0.5m). The second condition is that the 2 loudspeakers and the listening position form the points of an equilateral triangle. The third condition is that the loudspeakers are to be toed in by 45 degrees or more. The fourth condition is that the size of this equilateral triangle is set according to the room and the system. In a small room, or with a low-wattage amplifier then the triangle should be smaller; in a big room, or with a high power amplifier then the triangle should be bigger.

This is what is commonly known as near field listening. Its benefit is the reduction of the effect of the reflections from the walls on the direct sound, so that more precise imaging and a wide and deep soundstage can be achieved. This is the method to let you hear the most direct, the clearest and the highest amount of recorded details. A lot of reviewers prefer this method. This is also the preferred method of the designer of Venture Loudspeakers.
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5. The Long Wall Positioning Method

The loudspeakers are placed along the long wall of the room, which is the opposite of the norm. The rest of the method follows the Equilateral Triangle method. The listening position must be away from the back wall, minimum 1m distance.

With this method, the amount of midrange and bass energy will be boosted, soundstage depth will be reduced. If you are unsuccessful with methods 1 to 4, then you can experiment with this.

6. The Rhombus Method

The use of this method is limited to square rooms only. View the square space as a rhombus. The loudspeakers are placed along the walls that form 2 sides of the rhombus. The tips of the rhombus - behind the loudspeakers and behind the listening positioning, must be acoustically treated with round diffusers. The loudspeakers should not be placed too close to the walls.

This method is used specifically to cure excessive standing wave in the bass region. If you don’t want to use this method in a square room then move a lot of furniture into the room to tame the standing waves.

7. The Near Wall Positioning Method

This is the oldest method. Place the loudspeakers close to their back wall, the distance can be 20, 30, 50 cm, you can adjust according to your preference. Usually the loudspeakers do not need toe in.

Use this method when the highs are too sharp and the mids and lows are too thin. This method will add body to the mids and lows to achieve a better balance. The soundstage depth and width will be reduced, but compared to bad sound quality, sacrificing soundstaging to get a better sound is the correct way.

8. The Bookshelf Method

The 7 preceding methods are for floorstanders or loudspeakers placed on stands. This 8th method is for bookshelf loudspeakers used without stands. Usually, the loudspeakers will be placed on top of a oard or inside a bookshelf.

If the loudspeaker is on top of a cupboard, use a marble or granite slab as base, and use cones between the loudspeakers and the slab. In addition, place a bag of metal beads or a heavy metal piece on top of the loudspeaker to damp the vibration further.

If the loudspeaker is placed in a bookshelf, then make sure its top, bottom, left and right are stuffed with books (a thick magazine like the Audio Art is very useful here), make sure that the books are tightly packed, there must not be any loose space. Cones are not necessary.

You will get a sound that is solid and comes with good body. The highs will not be too sharp. The emphasis here is on getting a good tonal quality, soundstaging is secondary.

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Things to take note of: These 8 methods are those most commonly used. Usually there is one most suitable for your situation. However, there are 2 things still to be emphasized. 1: “loudspeaker positioning is not rigid; it is also not absolutely necessary to employ very precise measurement.” If you cannot achieve good sound with these 8 methods, then by all means go ahead and devise your own ways. Loudspeaker positioning is infinite. 2: “once you have found the right spot, the right method, the loudspeakers’ performance will be very sensitive to minute differences’. This is the time to do minor adjustments to get the best out of it.

The final emphasis: When positioning loudspeakers, the first principle to keep in mind is that there will be one position and one method in every room that will allow the loudspeakers to be most synergistic with the room. Finding this spot for the best synergy is what we seek for our loudspeaker position."