Understanding Music File Formats and Audio Concepts

Posted on Mar 22, 2025 in Electronics

Understanding Music File Formats

Music Formats:

  • WAV files: An uncompressed audio format.
  • CDA files: The format of commercial CDs, often larger in size.
  • MP3 files: Compressed files with acceptable quality.
  • AAC files: Uses a compression system reducing the size by approximately 30% while maintaining acceptable quality.
  • WMA files: Developed by Windows for use with Media Player; smaller than MP3s with similar quality.
  • MIDI files: A standard communication protocol for connecting musical instruments.

Music Playback and System Configuration

  • File managers: Used to play music in real-time while it is downloading.
  • Music players: Programs that can play different types of audio files (e.g., Winamp, AIMP2).

System Sound Configuration

The sound system of a computer focuses on audio output. Sound cards revolutionized audio, emerging with the rise of video games. Early examples include Sound Blaster. The sound card connects to the computer’s motherboard, typically at the rear. Most connections use mini-jack plugs, including MIDI.

Audio Inputs and Outputs
  • Input line: Connect devices with an acceptable sound level.
  • Mic input: Specifically for connecting a microphone.
  • Speaker output or line: Connect playback or recording devices.
  • MIDI connector: An interface for computer communication with musical instruments, using a special connector.

Multimedia Concepts

Multimedia is the combination of image, text, and sound.

Multimedia Software Categories

  • Multimedia software: Computer programs capable of handling visual information: text, voice, drawings.
  • Sound programs: For editing and playback of music.
  • Digital-image acquisition and image processing visualization.
  • Graphic design: Create illustrations, artistic designs.
  • Video: Editing and assembling films.

Understanding Sound

Sound is a vibration that propagates through the air. A disturbance traveling through the air is called a sound wave, and its form is known as a waveform.

Digital Sound: A sequence of binary numbers created by sampling and digitizing an audio signal. Transforming an audio signal requires a computer with a sound card and a microphone. Digitalization requires considering the sampling frequency and resolution.

Key Audio Characteristics

  • Sampling rate: The number of sound samples taken per second, measured in Hertz (Hz) or Kilohertz (kHz). Humans can typically hear sounds between 20Hz and 20kHz.
  • Resolution: The amount of bits used in each sample of the sound signal, expressed in kilobits per second (kbps).
  • Amplitude: The amount of force or energy of sound, measured in decibels (dB). The range is what we regulate with volume controls.
  • Noise: Random sounds from various sources that distort the main sound. Noise is measured in decibels and compared to the intensity of the main sound.