Numeracy

Introduction to Numeracy

  • Numeracy is the ability to understand and work with numbers and mathematical concepts.
  • It plays a crucial role in sound and audio technology, particularly in areas like signal processing, sound synthesis, and frequency modulation.

Measurement of Sound

  • Sound level is measured in decibels (dB), a logarithmic scale based on power ratios.
  • The range of human hearing extends from approximately 0 dB (threshold of hearing) to 130 dB (threshold of pain).
  • A change of 10 dB is perceived as roughly a doubling or halving of loudness.

Understanding Frequency

  • Sound frequency is measured in Hertz (Hz), with 1 Hz equivalent to one cycle per second.
  • The human audible range is typically from 20 Hz to 20,000 Hz.
  • Understanding frequency is crucial for tasks such as equalisation and pitch correction.

Waveform Mathematics

  • Sound is represented as a waveform, often a sine wave, which can be described mathematically.
  • Key parameters of the sine wave include its amplitude (peak level), frequency (cycles per second), and phase (starting point).
  • These parameters underpin digital sound synthesis and effects processing.

Digital Audio Concepts

  • Bit depth and sampling rate are two vital numerical aspects of digital audio.
  • Bit depth affects the dynamic range and noise floor of a recording: more bits means more detail.
  • Sampling rate, measured in kilohertz (kHz), represents the number of times the audio is measured per second. Standard CD quality audio uses a sampling rate of 44.1 kHz.

Applying Time Signatures

  • Time signatures and beat divisions are crucial in sequencing, sampling, and mixing.
  • Understanding and correctly applying complex time signatures can add creative depth to a composition.

Health and Safety Laws

  • Regulations specify the maximum permissible exposure to sound before it becomes harmful.
  • For example, an average noise level of 85 dB or more over an 8-hour workday can potentially cause permanent hearing damage.

Numeracy skills are fundamental to many aspects of sound and audio technology. A solid understanding of numerical concepts can enhance creativity, improve technical proficiency, and ensure compliance with health and safety regulations.