(음향강의) 노이즈잡고 음질까지 좋게하는 비법 공개! - 게인스트럭쳐(Gain Structure)하나로 1석 2조 - 노이즈가 많으세요? 이 영상 꼭 보세요

Summary

The video explains gain structure: setting the signal level appropriately at each stage of an audio system. The presenter’s central point is that a microphone signal should be amplified sufficiently at the first preamp stage, before it travels through the rest of the system. This can reduce the effect of noise and preserve sound quality better than recording the signal too quietly and raising its level later.

Main ideas

• The preamp is an important first stage. A microphone produces a low-level signal, so a mixer or audio interface needs to amplify it to a usable level. This matters in both analog and digital recording chains, since the signal must reach a suitable level before digital conversion.
• Later amplification cannot fully make up for a weak initial signal. Raising a quiet recording later may also raise noise and, according to the presenter’s demonstration, may not sound as good as setting the preamp properly at the outset.
• Keep levels consistent through the signal chain. Set the first stage to deliver a healthy signal, avoid unnecessary changes in level between devices, and use the final amplifier or output control to set the listening volume.
• Avoid clipping. “Turn the preamp up sufficiently” does not mean turning it up until the signal distorts. The presenter advises using a strong level while leaving enough headroom to prevent peaking and clipping. The percentage figures he gives are rough examples, not a universal calibration standard.
• The principle applies beyond studio mixers. For home audio, the presenter suggests raising the set-top box’s output to a suitable level, then adjusting the TV volume for comfortable listening.

Demonstration and suggested method

The presenter records speech with an SM57 microphone through a mixer connected to a computer by USB, then compares it with audio from a lavalier microphone.

1. Set the microphone preamp to a healthy level so the recording chain can capture the signal clearly.
2. Check that peaks do not clip or distort. Leave headroom rather than pushing the preamp to its maximum.
3. Keep levels reasonably consistent through subsequent equipment. Avoid sending an unnecessarily weak signal onward and relying on later stages to make it louder.
4. Set the final listening loudness at the output stage. Lower the amplifier or playback volume as needed for comfortable listening.
5. Compare this with a low preamp setting followed by increased levels later. Listen for differences in noise and sound quality, not just loudness.

The presenter argues that a recording with appropriate gain sounds better than one recorded with too little preamp gain and boosted afterward.

Speakers and sources featured

• Presenter: Identifies himself in the subtitles as Kim Do-won. The channel metadata names Previsions Dohun Kim, so the subtitle’s name may be an auto-caption error.
• Audio sources in the demonstration: The presenter’s voice recorded with an SM57 microphone and a lavalier microphone.
• Equipment and signal chain discussed: A mixer or audio interface with a microphone preamp, connected to a computer by USB. The presenter also applies the principle to home TV audio.