Bandwidth frequency

Professional Definition

Bandwidth is the absolute value of the difference between the upper and lower frequency limits of the frequency band.

In engineering terms, this parameter is usually denoted by the symbol B (from the English bandwidth) or Δf. Mathematically, it is a simple calculation: we subtract the lower frequency limit (f₁) from the upper limit (f₂), which gives us the formula: B = f₂ - f₁. In practical electroacoustics, bandwidth informs us about the range within which a device (e.g., speaker, microphone, or amplifier) processes sound with an acceptable level drop (usually -3 dB).

Acoustics in Simple Words

Imagine a wide highway. The more lanes it has, the more cars can pass beside each other at the same time. Bandwidth is like the width of this highway for sound. If the bandwidth is narrow (like a one-lane road), only certain sounds can “fit” on it – e.g., only human speech, as with old phones. If the bandwidth is wide (multi-lane highway), both powerful trucks (low bass) and fast motorcycles (high tones) can travel freely on it, creating a full, rich sound image.

Summary

Bandwidth is a fundamental measure of the operational range of an acoustic system. It defines the “space” in which the device operates effectively, directly affecting the fidelity and detail of the reproduced sound.