Sound Meter

^{by Marcel Huibers | Sound Development 2025 | Published under the MIT License}

Peak meter JUCE module with optional fader overlay.

Used in the Lobith Audio's waveform audio player PlayerSpecz.
Compatible with JUCE 8. For older JUCE version go check out the JUCE7 branch.

Features:

• Fully resize-able.
• Adaptive. Will show header, value, tick-marks only when there is space available.
• Unlimited number of user defineable segments, with custom ranges and configurable colours or gradients.
• Efficient. Only redraws when needed.
• Configurable meter ballistics (meter decay).
• Tick-marks (dividing lines on the meter) at user specified levels.
• Peak hold indicator and optional peak value readout.
• Optional label strip next to the meters (which can double as master fader).
• Optional header identifying the meter's name (set by user) or channel type.
• Optional fader and mute button (in the header).

New: Meter Presets!

• Default (-60 dB - 0 dB)
• SMPTE PPM (-44 dB - 0 dB)
• EBU PPM (-30 dB - -10 dB)
• Yamaha 60 Mizer (-60 dB - 0 dB)
• Bob Katz K metering (K20, K14, K12)
• Extended Bottom (-96 dB - 0 dB)
• Extended Top (-50 dB - +20 dB)
• Full Range (-96 dB - +100 dB)

You can find the API documentation here...
An example project, demonstrating sound_meter can be found here...

Usage

All classes are in the namespace sd::SoundMeter to avoid collisions. You can either prefix each symbol, or import the namespace.

MetersComponent

The MetersComponent class creates and controls the meters. This would live in your editor.h.

private:
   sd::SoundMeter::MetersComponent  m_meters;

In the constructor you can specify a channel format with setChannelFormat or set the nummer of channels with setNumChannels:

m_meters.setChannelFormat (juce::AudioChannelSet::stereo());

and configure it's options: (for all meter options, see documentation)

sd::SoundMeter::Options meterOptions;
meterOptions.faderEnabled     = true;
meterOptions.headerEnabled    = true;
meterOptions.showTickMarks    = true;
m_meters.setOptions (meterOptions);

and configure the segments:

std::vector<sd::SoundMeter::SegmentOptions> segmentOptions = 
{ // From bottom of the meter (0.0f) to the half. Displaying -60 dB up to -18 dB.
  { { -60.0f, -18.0f }, { 0.0f, 0.5f }, juce::Colours::green, juce::Colours::green }, 
  // From half of the meter to almost the top (0.9f). Displaying -18 dB up to -3 dB.
  { { -18.0f, -3.0f }, { 0.5f, 0.90f }, juce::Colours::green, juce::Colours::yellow },
  // From almost the top to the top of the meter (1.0f). Displaying -3 dB up to 0 dB.
  { { -3.0f, 0.0f }, { 0.90f, 1.0f }, juce::Colours::yellow, juce::Colours::red } };    
m_meters.setMeterSegments (segmentOptions);

Finally (still in the constructor) we add the component and make it visible:

addAndMakeVisible (m_meters);

In the resized() method, you set the bounds (left, right, width, height) of the meters:

m_meters.setBounds (getLocalBounds());

Getting the levels

Basically everything is set up now.
All left to do now is to supply the meter with the level with the method: setInputLevel (int channel, float value);

The recommended way to get the levels from the audio processor is to let the editor poll the audio processor (with a timer for instance). Preferably it would poll atomic values in the audio processor for thread safety.

A fully working example demonstrating this can be found here...

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Sound Development 2025