TLDR;
This video provides a comprehensive guide on how to properly use various types of microphones, particularly condenser microphones, for recording high-quality audio. It covers the inverse square law, optimal microphone distances, techniques for managing sibilance and plosives, and the correct way to boom a subject from above. The video emphasises the importance of balancing distance, room sound, preamp noise, and plosive control to achieve professional-level audio recordings.
- Understanding the inverse square law is crucial for maintaining consistent audio levels.
- Optimal microphone placement and angle can significantly reduce sibilance and plosives.
- Proper booming technique involves aiming the microphone at the upper chest/throat area while staying out of the camera frame.
Intro [0:00]
The video introduces the topic of proper microphone usage, focusing on condenser microphones. The presenter mentions previous videos on digital recording, microphone selection, and achieving good audio for YouTube, noting that this video will address common questions about microphone placement and optimal distances. The content is described as "nerdy stuff" aimed at helping viewers improve their audio recording techniques.
Inverse Square Law [1:12]
Dr. Stennetty explains the inverse square law, which states that the intensity of sound decreases by approximately six decibels for each doubling of distance from the sound source. Conversely, halving the distance increases the sound pressure level by approximately six decibels. This principle highlights the importance of maintaining a consistent distance from the microphone to achieve uniform recording levels. Moving closer to the sound source increases the sound pressure level significantly, while moving further away reduces it.
Distance [4:01]
The video discusses the impact of distance on audio recording quality, noting that while staying further back from the microphone might seem easier, it introduces noise and room sound. Increasing the distance requires raising the preamp volume, which can amplify unwanted noise. Additionally, greater distance captures more of the room's acoustics, potentially resulting in an amateurish sound. The optimal distance for spoken word or singing with a cardioid condenser mic is generally between eight inches to a foot, balancing proximity effect and room sound.
Sibilance Trick [10:10]
For microphones that tend to produce harsh sibilance, such as the Rode NT1A, the presenter suggests a technique to mitigate this issue. By twisting the microphone slightly off-axis, so it points to the side by a small amount, you can introduce controlled off-axis coloration that reduces the sharpness of sibilant sounds. The key is to make subtle adjustments, as excessive off-axis positioning can make the audio sound distant.
Shotgun Mic Technique [11:09]
The video transitions to discussing boom microphone techniques, particularly for shotgun microphones like the Sennheiser MKH 416. It addresses the common misconception that boom mics should point at the top of the subject's head. Instead, the presenter advises aiming the microphone at the upper chest/throat area. This technique minimises off-axis coloration caused by head movements. The ideal distance is as close as possible while remaining out of the camera frame, typically around a 45-degree angle. Using a foam filter can also help reduce plosives and improve sound quality, especially with sibilant microphones.
Recap [16:34]
The video recaps the key points covered, including finding the right balance between distance, room sound, preamp noise, and plosive control. It highlights the inverse square law, techniques for reducing sibilance by adjusting the microphone's axis, and proper booming techniques. The presenter emphasises the importance of good audio, noting that sound makes up 80% of a movie and 100% of an audiobook.