dBscaled

dBscaled is a term used in audio engineering and signal processing to describe a scaled representation of decibel values. It is not a standardized unit, but a convention used in software and analyses to map the logarithmic range of decibels into a bounded, linear-scale display for visualization and comparison.

The scaled value, commonly denoted S, is derived from a decibel value D through a mapping function. The most common form is linear normalization: S = (D - Dmin) / (Dmax - Dmin), where D is in dB and Dmin ≤ D ≤ Dmax. This yields S in the range [0, 1]. Dmin and Dmax are system-defined, often Dmin around -100 to -120 dB and Dmax around 0 dB or 0 dBFS. Some implementations use alternative mappings, including logarithmic compression, to preserve perceptual differences within a limited display range.

Applications of dBscaled include visual meters, histograms, spectrogram color scales, and user interface controls where a bounded, easy-to-interpret value is advantageous. It helps users compare channels or time points when the underlying dB values span a wide dynamic range, without requiring direct interpretation of raw decibel values.

Relationship to other scales: dBscaled is derived from dB and is different from absolute physical units. It is distinct from dBFS (decibels relative to full scale) and from linear amplitude representations. When implementing dBscaled, considerations include choosing appropriate Dmin and Dmax to match the signal’s dynamic range, handling out-of-range values, and applying smoothing for real-time displays to avoid jitter.

Notes: Exact definitions vary by software, so consulting specific documentation for a given implementation is advised.