Created on 04.11.2007 15:46.
Last updated on 22.11.2021 21:51.
Author: Nikolay Romanov ..
You bought acoustic systems (hereinafter we will call them simply speakers), connected them to an amplifier, but there is no sound. What’s the matter? And the fact is that the speaker system is simply not installed correctly. I have been doing (professionally) acoustics all my life, so listen to my recommendations. It is desirable that your room has a rectangular shape. For most speakers, the best results are achieved by installing them along a long wall.
When placing speakers, one should strive to ensure that the sound is even, without noticeable humps and dips, by moving furniture and using absorbing (carpets, curtains) and dissipating (bookcases and shelves) surfaces. The bass should be crisp, short and firm, like a taut trampoline. Keep in mind that shifting the speaker by just one centimeter globally changes the sound (I was convinced from my own experience). So go for it.
The listening position should be so that the speaker tweeters (tweeters) are level with your ears (see Fig. 1).
Correct positioning in height allows for more precise localization of the sound. The sound of bookshelf speakers in the bass area will improve dramatically if they are installed on special filling stands. Be sure to install the floorstanding speakers on the spikes.
Install the speakers so that the distance between them and the listening position is the same (see Fig. 2), that is, to form an equilateral triangle, or a little further.
Place a rug or rug on the floor 7 to enhance the upper bass and mids. But do not overdo it, otherwise the sound will be dead and lifeless, like with an open window. Very good results are obtained when gluing the ceiling with cork or corrugated foam panels.
By changing the angle of the speaker (see Fig. 3), you can significantly improve the localization of sound. Flip the speaker so that the socks are facing inward and position them so that the axes emanating from the speaker intersect at some distance directly in front of you. How to catch the sound in focus.
Install the speaker as far away from walls and corners as possible.
It is desirable that the distance from the back wall is different from the distance to the side wall. With the same distance to the walls, it is possible to fold the reflecting waves, or vice versa, their mutual destruction. As a result, there may be a hump or a deep dip in the “saddle” in the bass area and unpleasant bubbling.
As A. Likhnitsky wrote (А / М №4 2001). We are not in a position to influence the low-frequency rise. By moving the loudspeaker away from the walls and floor, we will only lower the frequency with which this rise begins. But we have the ability to minimize failure.
To do this, the dimensions X, Y, Z and 0.5d (see Fig. 4) should be selected not equal to each other. The question arises, what does not mean? The answer lies on the surface. It is necessary to compensate for the saddle formed due to the interaction of a loudspeaker with one imaginary source, a fuzzy maximum, which also arises as a result of the interaction of this loudspeaker with another imaginary source.
It is useful to make such compensation in each pair of interacting sound sources. As seen from Fig. 4, for such a compensation, it is necessary, among the dimensions X, Y, Z and 0.5d, to arbitrarily take two pairs and then set the ratio of dimensions equal to 1.7 in each of them.
In a listening room, this ratio can be determined at no cost (see Fig. 5).
After the loudspeakers are installed in the calculated position, it is advisable to clarify the free ratio between the dimensions X and Y (or Z and d) by the results of measuring the total power frequency response of the loudspeakers, and even more correctly, based on an assessment of the nature of the sound of the bass notes of the double bass and timpani.
And lastly, I would like to describe the point of view of A. Likhnitsky on the location of the listener in the listening room. The listener should be at an equal distance from the speakers of the stereo system, and the angle between them (with the top at his head) should be from 50 to 70 °
In addition, it must be in the balance zone of the amplitudes of even and odd, longitudinal, axial standing waves. I note right away that you will not get this balance if you try to position yourself in the center of the room, since there can only be zero amplitudes (nodes) of odd standing wills. The required balance must be sought by stepping back from the center of the room at a distance that is 10-15% of its length.
The easiest way to look for this balance is by ear. Play a recording of organ music through your audio system, and move the chair in which you are sitting back and forth to achieve acceptable articulation and ease of bass sound.
And most importantly, do not put stands and bedside tables between the speakers, if you still have a stand, then push the speaker forward or move the stand against the wall.