Why are there several pairs of monitor speakers in the recording studio- three

Why are there several pairs of monitor speakers in the recording studio- three
The most ideal room state is shown in the figure below, and the control room of most recording studios is also designed in this way. However, how to place the monitor speakers in the environment without strict acoustic design in ordinary houses, bedrooms and temporary buildings? Here are some principles for reference.
Based on past experience, I will briefly summarize the key points of speaker placement in non-standard studio environment. [Chinese dubbing]
First, the back of the speaker cannot be against the wall, and the left, right and rear of the speaker cannot be against the wall corner. The shape of ordinary rooms is generally irregular, so at least one meter of space should be left on both sides of the left and right speakers. If it is too close to the wall corner, the sound heard will also bounce through the wall to form multiple reflections, resulting in significant differences between the two speakers in timbre and even in loudness.
Second, place the speakers in strict accordance with the equilateral triangle. After determining the listening position, use a ruler directly to measure the most accurate sound. The sound is not the same one centimeter away. If you move for half a day, it's better to measure with a ruler. The sound is almost right when the position is right. If there is no condition to place a 120cm equilateral triangle, a 90cm small equilateral triangle can be considered. [English dubbing]
Third, in principle, there should be no obstacle between the speaker and the ear. One bottle and one cup will cause sound changes, which is called comb filtering effect in professional terms. The display will also damage the sound field to varying degrees. Therefore, many recording studios choose to use a projector as the display, or place the display diagonally at a lower angle, and try not to block or block the speaker as little as possible. [Animation dubbing]
For the setting and placement of monitor speakers, there is a booklet "Monitor Speaker Setting Guide" from Genelec, which is easy to understand and can be read for reference. For general rectangular rooms, how to optimize the monitoring environment, there are several suggestions in the "Monitor Speaker Setting Guide":
Before purchasing a monitor speaker, you should take into account the room factor. If the room environment is not ideal enough, you can not play the potential of the monitor speaker, nor can you hear the correct sound.
Listen to the topic of speaker selection. I didn't plan to start today. Now that I have written here, I would like to briefly mention a few points:
If you have any questions about the purchase of monitor speakers, please leave a message in the comment area and have the opportunity to write a separate article. It is better to give the budget and the equipment around you. If you don't give the budget, you can compare the purchase of monitor speakers. That is playing hoodlum.
Statement: This article is original and reprinted in part. If reprinted, please indicate the source and source. I am the editor of Voices100, a multilingual self-help live dubbing network