What is gain in audio?
Gain is the amount of amplification applied to a microphone signal before it is recorded. It controls how loud or quiet the audio input appears in your recording. Too little gain produces a quiet signal buried in noise. Too much gain causes distortion and clipping.
Setting gain correctly
The goal is to set gain so that normal speech or performance peaks at around -12 to -6 dB on your audio meter. This gives you enough signal strength for a clean recording while leaving headroom for louder moments.
If your audio peaks are below -20 dB, the gain is too low. The signal is weak and raising it in post amplifies the noise floor — producing audible hiss.
If your audio regularly hits 0 dB, the gain is too high. The signal clips (distorts) and the distortion cannot be removed in post — it is permanently baked into the recording.
Gain vs volume — the difference
Gain is applied at the input stage — before the signal is recorded. It determines the strength of the raw recording.
Volume is applied at the output stage — after the signal is recorded. It controls how loud the playback is through speakers or headphones.
Setting gain correctly is critical because it determines the quality of your raw recording. Volume can be adjusted freely afterward without quality loss.
Think of gain as the quality control at the source, and volume as the playback knob.
Audio equipment at Camera Shop Egypt
Gain tips for different situations
Interviews: Do a sound check before recording. Ask the subject to speak at their normal volume and set gain so peaks hit -12 dB. Leave headroom for laughter and emphasis.
Music and loud sources: Start with gain low and increase gradually. Musical instruments can have dramatic volume spikes.
Wireless mics: Set gain at the transmitter (mic) and receiver separately. The transmitter should capture a strong signal, and the receiver should deliver the right level to your camera or recorder.
Camera audio: Camera preamps are often noisy. If possible, use an external recorder with better preamps and sync audio in post.
Always wear headphones while recording to monitor gain in real-time. You can see levels on a meter, but hearing the audio tells you immediately if there is noise, distortion, or interference that the meter might not clearly show.