6.13 Spectrum Analyzer

Spectrum Analyzer in 1.2 and earlier

Spectrum Analyzer

This plugin visualizes the frequencies present in the signal it monitors.

Graph

  • X axis: shows frequencies from 20 Hz to 20,000 Hz, divided into octaves (this makes the X axis appear nonlinear).

  • Y axis: shows amplitude from 40 dB to -60 dB (displayed linearly with respect to decibels).

Buttons

  • Linear Spectrum: toggles linear display of frequencies (rather than by octaves).

  • Linear Y axis: toggles linear display of amplitude (rather than by decibels).

Spectrum Analyzer in 1.3 and later

Spectrum Analyzer

Buttons

  • Waterfall:

  • Averaging: enables averaging of display frames.

  • Stereo: enables the display of LR channels independently, with the Left channel represented by Blue and the Right channel by Red.

  • Peak hold: enables a "ghost" line that shows the peaks of the spectrum.

  • Pause/Play button: enables/disables the plugin.

  • Snowflake: freezes plugin display (along with the data displayed).

  • Frequency Range : alters the range of displayed frequencies.

  • Amplitude Range : alters the range of displayed amplitude.

  • FFT Block Size : alters the frequency resolution of the display (Higher resolutions come at the cost of FPS).

  • FFT Window Type : changes algorithm used to remove FFT-related noise.

    • Blackmann-Harris displays the least noise but has low frequency resolution.

    • Rectangular displays the most noise but has high frequency resolution.

Graph

  • X axis: shows frequencies based on the Frequency range drop-down menu.

  • Y axis: shows amplitude based on the Amplitude range drop-down menu.

Clicking in the spectrum/waterfall display adds a ruler/cursor with value readouts.

Advanced

  • Envelope Res: alters the resolution of the Peak envelope ("Peak Hold").

  • Spectrum Res: alters the resolution of the display curve with fill-in color.

  • Falloff Factor: alters the speed at which the peak envelope ("Peak Hold") falls to zero.

  • Averaging Weight: alters how the display curve reacts to new samples.

    • High value: fast reaction, low jitter reduction. enables real-time spectrogram.

    • Low value: slow reaction, high jitter reduction.

  • Waterfall Height: alters the time range, or the amount of temporarily stored frames, of displayed frequencies in the Waterfall display.

  • Waterfall Gamma: alters the amount of gamma correction in the Waterfall display.

  • Window Overlap: alters how many times each FFT sample is processed (higher values can help improve FPS).

  • Zero Padding: improves resolution when using a smaller FFT Block size, at the cost of performance.