Levels

Understanding “Levels” in Audio Technology

Dynamic Range

• Dynamic range denotes the difference between the softest and loudest part of a sound or piece of music.
• It is measured in decibels (dB) and it can greatly affect the perceived quality and emotional impact of a recording.
• Maintaining a good dynamic range can prevent audio distortion and ensure a balanced mix.

Mic Level

• Mic-level signals are the weakest signals and are generated by microphones and some other low-level output devices.
• These signals require pre-amplification before they can be processed by other audio devices.
• Mismanaging mic-level signals can result in noise and distortion.

Line Level

• Line-level signals are stronger than mic-level signals. These are typically produced by synthesizers, mixers, and other signal-processing devices.
• Line-level signals are standardised to maintain signal noise, quality, and compatibility across different equipment.
• There are two types of line-level signals: consumer (-10 dBV) and professional (+4 dBu).

Instrument Level

• Instrument-level signals, such as those from electric guitars and basses, fall between mic-level and line-level signals.
• These may require a Direct Injection (DI) box to match impedance and voltage levels with other audio devices.

Speaker Level

• Speaker-level signals are the highest voltage signals and are demonstrated by amplified signals sent to loudspeakers.
• Amplifiers are used to increase line-level signals to speaker levels, providing sufficient power to drive the speakers.
• Recognising speaker-level signals is essential to avoid accidental harm to equipment or loudspeaker blowouts.

Digital Audio Levels

• Digital audio levels manage volume in digital audio systems.
• Signals are represented as binary numbers without an inherent ‘volume’, so digital audio levels are typically managed through Digital to Analog Converters (DACs) and gain settings on Audio Interfaces.
• Values are often represented in dBFS (decibels Full Scale) where 0dBFS is the maximum allowed level before digital clipping occurs.

Balancing Levels

• Equalisation (EQ) is a technique to balance levels across different frequency bands.
• Compression can help to control dynamic range by limiting the amplitude of loud signals or amplifying soft ones.
• Gain staging involves the process of managing volume levels from various audio sources to ensure a clean signal path throughout an audio chain.

Understanding ‘levels’ in audio technology is crucial for obtaining a clean, balanced, and high-quality audio output. It involves knowing how to acknowledge and manage different signal strengths at each stage in the audio chain – from the initial capture right through to final output.