It looks like just a very ordinary mixer, but in actual operation, it is as difficult to control as a devil (this is the kind of devil that pays no money), and it will make your carefully crafted soundtrack. All ruined. If the gain process is set randomly, that is, the gain of each part of the line from the signal input terminal to the signal final output terminal, it will cause unexpected distortion, "hissing" sound, and many other annoying sounds.
However, blindly reducing the signal level is not the key to solving the problem. If the gain of the signal level is too small, the inherent noise level of each device will reach an audible level, so you will hear a lot of noise, as if you have made a very large gain. The technique required at this time is to use enough gain to keep the sound clean and full of vitality, without causing distortion or "popping" sound, and not destroying the sound quality and clarity of the sound.
For typical sound signals, if you use the following method, it will be difficult to operate, that is, use a microphone to pick up the signal, and then use the microphone preamplifier, some channel faders, an auxiliary send, an effects processor, and the main fader. Finally, it is input to the input terminal of the recorder.
If you want to make the recording work more concise and effective, you should pick up the sound signal from the microphone (or the sound of the electronic musical instrument output line level) and directly input it into the recorder, and then gradually adjust the settings of each device in the subsequent steps. Gain process.
The signal line starts from the source of the sound, so if your microphone doesn't work, then everything is lost.
Dynamic microphones can withstand higher input levels without distortion, but if you are using a more sensitive condenser microphone, you must pay attention to the clean and clear signal. Snare drums, guitar amplifiers, singers, and other dynamic sound sources produce impact and loud sounds that can cause microphone distortion, and this distortion can be heard.
Many condenser microphones have an attenuation switch of at least 10dB, so when you hear a "hum" sound in the middle frequency range or noise in the high frequency range, turn this switch on (the phenomenon of spray microphones in the low frequency range is usually It's all caused by the singer "blowing" on the microphone).
If the distortion still exists, move the microphone a little further away from the high sound source. If the microphone cannot pick up sound at this time, it may be that you have selected the wrong type of microphone-this type of microphone is not suitable for your current job.
Musical instruments with line output
Simply add the sound of the bass, guitar, keyboard, or other tone generator module to the mix. What problems will occur?
The problems are many. Since electronic musical instruments have built-in pre-amplifiers, if you suddenly increase the volume occasionally, you will hear a slight clattering sound. When this happens, you should adjust the line output level of the electronic musical instrument to 75% of the maximum volume level.
What we are going to talk about below is really the kind of thing that will get you into trouble. How to set up the microphone/line preamp on your mixer.
If you turn all these gain knobs to the maximum, you will definitely hear very serious distortion and "hissing" sound, especially when the post-amplification equipment you choose is a relatively inexpensive product. . When the fader of the mixer is raised to a higher position or the volume of the amplifier is louder, all annoying sounds will pop out.
In order to avoid this situation, the most effective solution is to set the magnitude of each gain to 75% of the maximum gain value. If the situation still does not improve after you do this, then turn on the channel attenuation switch on the mixer (assuming your mixer has this function). If there is no such button on your mixer, lower the preamp level until the distortion disappears.
The next step of gain adjustment is the fader of the mixer. Obviously, it is very important to use faders to balance the preamp of the microphone/line. Here, I can recommend a better adjustment plan to you:
Place the fader at 75% of the maximum level. Then, slowly increase the preamplifier of the microphone/line until the signal level is appropriate (we will discuss the recording level later).
Listen carefully to see if there is a "hissing" sound or distortion. In the most ideal situation, when you adjust the position of the fader and the preamplifier of the microphone/line to 75% of the maximum volume, the sound is very powerful and full of vitality.
If you have to adjust the fader or microphone/line pre-amplifier to almost the maximum volume during operation, you can achieve this effect (it is possible that you are recording a whisper or other extremely weak sound), then You must listen very carefully to make sure that the sound is satisfactory. When you encounter this situation, who should you promote, pre-amplification or fader? The final answer depends on the degree of distortion of your device and the judgment of your ears as you continue to experiment.
You can group several signals into a group for auxiliary mixing, such as combining the background vocal chorus of several audio tracks into a stereo audio track, or sending a single audio track to the stereo input End-add other signals.
Still, we have to abide by the "75%" rule mentioned above. If you encounter sound distortion, then you can lower the faders of each channel, group faders, and the preamplifier of the microphone/line separately; until the sound distortion problem is solved.
There are 3 gains available for adjustment here, you have to keep adjusting and listen carefully.
When you connect the effects processor to the line through the auxiliary transmitter, the situation becomes a little more complicated.
First of all, use the "75%" rule to adjust the auxiliary send level knob to 75% of the maximum level. Then check whether the input level of the effector is broken. This is not a simple matter. At least it is more complicated than making the effector emit a sound. Because all effectors have different reactions to the input signal.
For some devices, you will find that the level indicator has hit the red overload area, but the sound is still very clean. For other devices, as soon as the level indicator touches the red area, the sound is no longer available (a bit too much, but at least the sound is distorted). Until you fully grasp the characteristics of an effector, you can adjust the input level correctly and use it safely.
If at this time you find that the input level is adjusted too low, that is to say, those "hissing" and "digital" sounds are audible, then adjust the input level to about 75%. At this time, you must be careful not to let the red overload indicator light up too much. When you set the appropriate level, don't think about the indicator lights anymore, just listen with your ears.
Joe Meek, a home studio recording expert,’s view on this issue is: "If the sound sounds good, then it is good!"
Mixing to an analog tape recorder is a more forgiving job. In most cases, you can allow the pointer to hit the red overload area, when the sound is the best. This seems to be contrary to the most common sayings we hear on weekdays, but as long as you try it yourself, you will understand.
However, depending on the characteristics of your tape recorder and the characteristics of the tape used, the above-mentioned "hit to the red overload zone" rule may also bring you terrible sound distortion. But then again, following this law usually allows you to get a very powerful and energetic voice. How to use it, let your ears judge.
Compared to analog recorders, digital recorders are not as forgiving. If you are recording with a digital multitrack or DAT, the level indicator hits the red area, or exceeds a certain pass-me indicator point, then your recording has failed.
There is a rule that always applies, a very simple rule: be sure to keep the level below the red overload line!
There are two basic ways to ensure that your voice is not distorted. The first method is to limit the level of the audio track, or thoroughly grasp the volume range of the sound source, and then set the maximum level of the audio track. The second method requires you to have enough time and great patience to play back over and over again, until all the volume is up to the requirements.
There is a more courageous way, that is, set the input level to just below the overload point, and then start praying. Obviously, the more familiar you are with the dynamic range of an instrument, the more and more effective you can use.
You have to learn to trust your ears, and not just trust the level meter. In fact, you can't guarantee that the display of the volume indicator or LED indicator on the music device is completely correct, but you must be able to hear the flaws in the sound. People who cling to the instructions can't record good voices (think carefully about this sentence).
Also note that the use of an equalizer on the front-end power amplifier or mixer will affect the gain of the device. Therefore, in actual operation, you must perform one step (such as boosting certain frequency bands), just verify What happened to the sound.
Finally, remember that when the recording indicator lights up, the musician's performance will become more powerful and imposing. So when you check the volume and set the basic level, don't fully believe the sound level of the performer at this time. When recording, the volume is likely to be 2 dB to 5 dB higher than this. The simple solution is to set aside a certain margin in advance, and you will benefit from it.