A few years ago I posted on the Polish version of the blog an article how to set up speakers in the room.
These are few simple tips to optimize your listening experience.
It can be obvious for many but you keep asking for an advice so I am reposting this also in English.
Careful positioning of loudspeakers is crucial to the achievable sound quality, in this case stereo. Unfortunately, there is no one universal recipe for this, because each room, has its own acoustic conditions. First and foremost, the size of the room, including the height and shape of the room, matters, which especially affects the way low frequencies are reproduced. Each room, just by virtue of its size alone, has its own set of resonances that affect the reproduction of low frequencies. Standing waves are created between parallel walls, which reinforce each other in some places and weaken in others, and the differences in sound level between these places are very audible. An additional factor affecting the sound is the material from which the walls of the room are made. A brick wall reflects or absorbs sound waves differently, while a drywall wall reflects or absorbs sound waves differently, and a wood wall absorbs sound waves differently. The stiffer the walls the better. The same applies to the floor. It is worth mentioning at this point that, for example, a drywall wall, especially when it has the possibility to work, acts like a membrane and essentially degrades the acoustics of the room.
Good bass reproduction in small rooms therefore poses some challenges. By small rooms, we mean living rooms, or even large living rooms in homes, and good bass is not rumbling or uncontrollable rumble, but the right timbre and intensity of sound correct enough that the sound does not seem dry. This is of capital importance for good music reproduction. Low frequencies - up to about 400-500 Hz (which is roughly more than half the keyboard of a piano starting from the lowest tones), radiate around the speakers regardless of which way the front of the speaker is pointed. It matters how the speakers are placed in the room relative to its "built-in" resonances, because what we hear in terms of bass is the result of the superposition of direct and reflected sound waves. In addition, bass will be heard differently in each location of the room, since the position of the listener relative to the location of the room's resonances is as important as the sound source. For this reason, it is impossible in a stereo system to position the speakers so that bass can be heard equally in every part of the room.
By positioning the loudspeakers with respect to the walls in an appropriate way, the bass intensity at the selected listening position can be enhanced or weakened. Due to the nature of low-frequency sound waves reproduced in a room with parallel walls, bass amplification is achieved by positioning the loudspeakers on even lines dividing the room between the front wall (on which the loudspeakers stand) and the rear wall. To plan the placement of speakers, it is useful to use a grid dividing the room into even parts along and across. The figure shows an example of the division with red lines into four sections and gray lines into six, with axes 4 and D being common to both divisions.
Positioning on the longer or shorter wall?
If we are comfortable with experimentation and freedom of arrangement, it's best to see in which arrangement the sound suits us best. For example, positioning the speakers along the long wall at points B4 and F4, on the line of equal division of the room in half with the listening position on the rear wall on the D axis should enhance bass reproduction, and due to the distance from the side walls should create optimal conditions for rendering the stage, which is affected by higher frequencies. This is because in this setting the higher frequency sound reflected from the side walls reaches the ears with such a delay, relative to the sound emitted directly from the speaker, that we recognize it, as background. When placing the speakers on the shorter wall at points such as D2 and D6 with the seat against the wall on axis 4 due to the narrowing of the width and the approximation of the side walls will worsen the scene.
Depending on the arrangement possibilities, it is worth experimenting, trying to place the "listening triangle" on the appropriate intersections of the even split lines, looking for optimal low frequency reproduction. In the event that the speakers, along with the room, produce too much bass, you can reverse the priority and use the room's odd division grid (grid with green axes division three and gray axes division five) and see how the sound will behave in such an arrangement.
The starting point is usually to position the speakers so that they, along with the listening position, form the vertices of an equilateral triangle. With these divisions in mind, one can further experiment with the spacing of the columns, which affects the width of the music stage. Too much spacing will cause it to break up. This can be easily heard, as the sound will clearly come from two separate speakers leaving an empty space in the middle. From this, the reproduction of mid and high frequencies will also be crucial. To give perspective, I'll add that the audible bandwidth for a young person with good hearing is from 20Hz to 20,000 Hz, with the highest note played on the piano (the far right key, or highest C) being 4,200 Hz.
For optimal speaker spacing, it's best to use a mono recording such as Miles Davis' excellent 'Round about midnight, recorded in 1956 by the Columbia label. With the speakers properly spaced, Davis' Quintet will literally hover in the air facing the listener.
Then you need to adjust the orientation of the speakers to the listener, thus "fine-tuning" the reproduction of the instruments' locations. It is worth noting that the listening spot where you get the full sound, the so-called sweet spot, is limited in the case of a stereo recording. This is because the stereo illusion is achieved at the point where the axes of sound leaving the speakers and reaching the listener at the same time intersect. Moving away from this point causes the sound from one speaker or the other to reach our ears later or earlier, and this worsens the stereophony.
Orientation tuning can start by positioning the speakers so that the speaker axes point perpendicular to the wall behind the listener, and then gradually rotate them toward the listener. Sometimes good results are achieved when the speaker axes aim at the listener's ears, sometimes when they cross just behind or just in front of the listener. It depends on the acoustics of the room, the directivity of the speakers and the individual preferences of the listener. I would only add that the directivity of the speakers is the range of angles in which all the frequencies emitted from the speaker are played at the same volume, because always a deviation from the main axis of the speaker causes a decrease in volume - the farther from the main axis of the speaker the full range is heard the better.
I suggest setting up the Closer Acoustics speakers so that the axis of the right column is aimed at the left ear, and the axis of the left speaker is aimed at the right ear. Such an arrangement gives the fullest picture and enlarges the field of optimal stereo listening, and under optimal conditions helps you feel a bit of the atmosphere of being in a concert hall.
Furnishings, carpets, curtains, armchairs, sofas, bookshelves affect acoustics by reflecting and absorbing high frequencies in particular, reducing (lots of furniture) or increasing (little furniture) the amount of reflected sound waves. A room that is too soundproofed will significantly reduce listening comfort, causing the music being played to seem unnatural and the space contained in the recording not to be felt. On the other hand, the lack of any materials to dampen reflections will blur the sound image and make it difficult to locate instruments on stage. Here, a reasonable compromise will usually suffice, with carpet being rather advisable. If necessary, sound wave absorbing material can be used on the wall behind the speakers to reduce reflections. In addition, the side walls should rather be left undamped, where the first reflections of sound waves coming from the speakers are, which should promote sound spatialization. Finally, a damping material can be placed on the rear wall behind the listening area to reduce the amount of reflected sound reaching the listener from behind, which can improve instrument localization.
In practice,due to furnishings, room layout and a whole host of other living space designpriorities, an optimal setting can be difficult to achieve. It's worth it,though, to keep these few basic principles in mind. Sometimes, for example,when considering the choice of an apartment, choosing a home design or creatingone yourself, you can pay attention to certain aspects that can be crucial toyour subsequent enjoyment of music.
While I am far from practicing audio voo doo, I would like to point out basic guidelines that can do a lot. I assure you that sometimes even small adjustments to the setting have an excellent effect on improving the quality of the listening experience, e.g. a cello sounds fuller and deeper, or a"piano" turns into a piano, or the hoarseness in a singer's voice becomes sort of more throaty :)
