"Come on, the master should give you a greeting gift, today let's learn how to get rid of the howling, do you know what the howling is?" Rao is a rational monster like Hong Tao, and he can't bear to refuse her request, and of course he can't really let her beat his legs and pinch his shoulders. Pen × fun × Pavilion www. ｂｉｑｕｇｅ。 The windows in the info control room have no glass and no curtains, so that you can better listen and observe the situation in the hall, but everything that happens inside can also be seen from the outside. is such a big man, let a little girl-like Dong Cai beat her legs and pinch her shoulders, what she knows is that she is short, and she thinks she is molesting a young girl.

"It's the kind of sound that comes out of the speaker that is particularly high-pitched, my former master said that there is this sound and then the microphone is gone, if the guest sings with this kind of sound, turn down the volume of the microphone, and then push it back when the howl is gone. This question asked Dong Cai to answer again, and the two DJers seemed to really don't know much about professional audio, and it could be seen from their eyes that they didn't understand it at all.

"That's right, the scientific name of howling is called positive feedback, which probably means that the sound in the microphone is amplified by the power amplifier, and then received by the microphone, and then amplified again, and keeps circulating, the intensity is getting higher and higher, and finally it becomes howling. You can't deal with this kind of positive feedback by shaking, and you can't turn down the volume, that won't solve the problem. Today I will teach you how to eliminate this kind of positive feedback, and you can't keep it at all! This is the rule of our business, whoever makes the equipment scream, who is a mallet, will be looked down upon by people who know how to do it. Seeing that the audio knowledge structure of these three apprentices was quite different from each other, Hong Tao did not plan to let them go hand in hand. After all, I didn't come to take apprentices specifically, and I didn't have so much time to give them a little make-up lesson from scratch, so let's focus on Dong Cai first, Dai Caixia and Liu Beibei can only watch the creation.

"A must...... Hey, hey, hey......" Dong Cai was very happy and naughty when she heard that Hong Tao really wanted to teach her to learn things, and deliberately learned Hong Tao's tone to speak, making the other two girls laugh.

"See these two big guys, right?" Hong Tao didn't care about others joking with him, even if it was an apprentice. He's a broken mouth and doesn't do anything right, he likes to joke and joke, and he doesn't think it's disrespectful. If everyone communicates seriously, he feels very awkward.

"I haven't seen this device before......" Dong Cai saw Hong Tao pointing to the two devices on the cabinet, his fingers biting into his mouth again, squatting in front of them and looking hard, as if he could understand.

"You've seen them, and you've got to use them, as long as it's a professional audio system, you have to have them. They're called equalizers, but they're all about the same and powerful, and you've probably seen an equalizer that's thinner than them before, with four or five knobs on them, right?" Hong Tao shook his head slightly, he hadn't even seen a segmented equalizer, so he dared to say that he was capable, this little girl really dared to open her teeth.

"Oh...... I've seen it, I've seen it, this thing is used by Bundy, and it's used to accentuate the bass, right!"

"Fart, accentuated bass, your former master either blinded you, or he didn't understand. I think it's more likely that the former is afraid that he will teach you to steal your own job. Listen, it's called a 31-piece equalizer, why are there two? Because we have a two-channel output, that is, the left and right channels, so one channel is one. What is it used for? It can divide the sound frequency band that our human ears can hear into 30 sections, and each small fader tube has a section, and adjust the amount of electrical signal in each section. In different occasions, the sound field is different with the different shapes, materials, and equipment performance of the space. For example, some places may have a large amount of feedback to the 500 Hz frequency band, some places may have a large feedback volume to the 5,000 Hz frequency band, and some places may absorb an additional 10,000 Hz of high frequency. In this way, the whole sound field changes, where 500 hertz is too strong, the bass will be very muddy, and there will always be a buzzing echo; if there is more than 5,000 hertz, the human voice will become very hard, and the loud and excessive harsh; if the high frequency of 10,000 hertz is less, the vocals and music will appear opaque. What do you do at this point? Do you see these 30 little faders above? They can dramatically adjust the level of these bands depending on the sound field. If there is more, we will pull it down, attenuate this frequency band, and if there is less, we will push it up to strengthen this frequency band. The end result is to compensate for the inherent deficiencies of the sound field environment, so that the sound is as full as possible but not redundant. Pointing to Jun Shiqi and saying a lot, Hong Tao looked at the three girls next to him from the corner of his eye, yes, six pairs of eyes and three pairs of children were confused, and they didn't understand much.

"Come on, it's not interesting to just talk, I'll show you how good your ears are. "If you don't understand, you can't force it anymore, which will make the three of them lose interest and become bored with learning. Hong Tao decided to use experiments to let them feel what 500 hertz, 800 hertz, and 10,000 hertz are. As long as they can hear the difference, it is progress, and at the same time, they can roughly understand what they mean. Then you have to read the details of the book, through continuous reading, continuous trying, to train your ears well, there is no other way.

In fact, the most important thing in the daily work of a tuner is a pair of ears and rich experience on the spot, the former is the foundation, and the latter is the guarantee. The ear is innate, just like the human voice, it can be improved a little bit through acquired practice, but it cannot be fundamentally changed, a good voice is good, a bad voice is bad, no rut. However, for a tuner who works in a night club, most normal people's ears are sufficient, but they have to get used to concretizing and quantifying sounds. Ordinary people hear a piece of music and listen to its melody, but the tuner hears not only the melody, but also the frequency of which segments it changes, and this kind of hearing is acquired by training.

Of course, if you want to be a top tuner, or if you want to be a recording engineer, you have to ask for the talent of the ear, and the light technology is useless. The theoretical hearing range of the human ear is from 20 hertz to 20,000 hertz, which is also the so-called acoustic audio range, and sounds below and above this frequency range are inaudible. However, this is theoretical, and the average human ear cannot perceive frequencies below 80 hertz and above 14,000 hertz, and only a small number of people can clearly hear it, which is talent.

Adjusting the equalizer is actually the process of using equipment to change the sound field environment, which is also the heaviest, most boring, and most critical work when the tuner first arrives at a place. Based on his ears' judgment and understanding of the sound field environment, he adjusted the 62 frequency bands on the two equalizers to the optimal position one by one. And this best is still dynamic, the best for vocals is definitely different from the best for music, and then it is a matter of experience. Is it more inclined to the vocals, or more to the music, or more detailed, simply come up with two or even three sets of schemes, some are biased towards the vocals, and some are biased towards music.

In some cases, it has to be subdivided. There are also different pronunciation methods such as male voice, female voice, lyrical, ethnic, bel canto, rock and roll, and folk music, orchestral music, light music, pop music, jazz music, rock music, heavy metal, and Di qu. If you want to be perfect, you have to continue to refine and try to bring out the characteristics of each sound. Fortunately, the night club is not so demanding, if you want to do it, it will be a professional concert level, Hong Tao can do it theoretically, but he has never actually operated it, and he is still a novice in this regard.

What Hong Tao needs to do now is to adjust the equalizer into two sets of schemes, one is the usual singing mode, and the other is the Diqu mode, which is enough for him to be busy, at least two days, and he can't be in a hurry, he has to tune little by little, listen carefully and try carefully over and over again. Because sound is a manifestation in an empty hall, when there are many people, the human body itself is a sound-absorbing material, and the sound field will change, and these variable parameters must also be taken into account.

It sounds complicated, but it's actually a hassle to do. Adjusting the equalizer requires someone to hold a microphone and walk around the hall at a loud volume, and while walking around, they have to rush to the microphone to pronounce and look for points where positive feedback may occur. Once you find this point, you have to use your hearing to roughly determine what frequency band it is in, and then adjust the level of the corresponding band down on the equalizer until there is no positive feedback.

This is only the first step, and once all the positive feedback points have been suppressed, it depends on how many faders on the equalizer are pulled down and how much they are pulled down before deciding on the next move. If you pull down too many frequency bands and too hard, then this environment can't ask for effects, so make do with it. Again, tuners are not omnipotent, there are too many congenital deficiencies, and they can't be made up for by the day after tomorrow. This is also the reason why the sound-absorbing panel is installed, and it is better to lose part of the aesthetic sense than to raise the sound field environment.

Specific to this hall, Hong Tao found a total of three positive feedback points, and all of them were on the stage. This shows that those sound-absorbing panels worked, not in vain, and the money was not spent in vain. It wasn't until the evening that these three points were determined. Dong Cai is the character who takes the microphone and listens to Hong Tao's instructions to wander around, of course, the hard work has to be done by the apprentice, as the master, Hong Tao just sits in front of the mixer in the control room, listens with his ears and tunes with his hands.