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Signal Analysis Features

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Overview

The WVC-PRO includes onboard signal analysis hardware that gives you real-time visibility into the quality of the audio signal passing through the unit. This includes an oscilloscope view, an FFT (Fast Fourier Transform) frequency spectrum, and clip detection. Features typically found only in dedicated bench-top audio analyzers.

Available Analysis Screens

Oscilloscope View

Displays the signal as a time-domain waveform: the classic "wave shape" view. Use this to:

  • Confirm a clean sine wave is passing through
  • Visually identify hard clipping (flat-topped waveform)
  • Compare signal shape before and after gain changes

Starting in firmware 4.0.0, the oscilloscope view on the WVC PRO-6 touchscreen is fully interactive:

  • Zoom through several discrete zoom levels to inspect a single cycle or view a longer stretch of signal.
  • Drag with your finger to pan through time, left or right, and move the trace vertically.
  • Freeze the trace to hold a moment of signal still while you inspect it, then resume live capture.

FFT / Equalizer View

Displays the signal as a frequency-domain spectrum, showing which frequencies are present and at what levels. Use this to:

  • See the frequency content of music or test tones in real time
  • Identify harmonic distortion (unwanted frequency components)
  • Monitor the output of your head unit or DSP for signal quality issues

Real-Time FFT (Multi-Channel)

Available on the WVC Pro 6 via firmware update, this view shows the FFT spectrum across multiple channels simultaneously, allowing you to monitor all connected amplifier inputs at once. On the WVC's on-screen display, all six channels are arranged in a 3x2 grid so you can watch every input at a glance without switching screens.

A CLIP indicator appears on any channel panel when clipping is detected on that input. Starting in firmware 3.10.0, all six channels (CH1 through CH6) report clipping; previously only CH3 through CH6 were flagged. Severity is shown by color: yellow for mild, orange for moderate, red for severe, so you can see at a glance which input is being driven too hard and dial back the source level.

Note (firmware 3.10.0): Clip detection is now driven by a signal-classification engine that distinguishes real clipping from clean tones, deep bass, and rebassed material. Clean sine sweeps, quiet music, and silence will no longer trigger false CLIP warnings, while real saturation is still detected reliably and reported within a fraction of a second instead of after several seconds. Firmware 4.0.0 further refines this so clean test tones and bass-heavy music no longer false-trigger the indicator.

Note (firmware 4.1.0): A new Clip Detection setting lets you choose how readily the CLIP indicators light up, with four levels:

  • Off: Clip detection is disabled. No CLIP indicators appear on any view.
  • Low (default): Only clearer, more obvious clipping is flagged. Best if you want the indicator to stay quiet during normal listening.
  • Medium: A balanced setting that flags moderate clipping as well.
  • High: Flags clipping most aggressively, catching even brief or marginal clipping.

Change the setting from the WVC PRO-6 touchscreen (Settings, Options tab), from the Knob menu (when the Knob is paired with a PRO or PRO-6 base on firmware 4.1.0+), or from the AuralSync app. Whichever surface you change it on, the new value syncs to the others, so the touchscreen, Knob, and app always agree. Clip detection is a PRO-only signal-analysis feature, so this setting is available on WVC PRO and WVC PRO-6 hardware only.

Starting in firmware 4.0.0, every channel panel also shows a peak-frequency readout ("Peak: x Hz"), so you can confirm at a glance which tone is dominant on each input. When a tone sits above the analyzer's measurable range, the panel shows ">2kHz" instead of a numeric value, so a high-frequency tone is never mistaken for an in-range reading.

CLIP Indicators on the RTC and Knob

Per-channel clip information is also streamed to remote displays:

  • RTC (firmware 3.10.5+): A CLIP pill appears next to the channel label on the FFT, oscilloscope, FFT Hi-Res, and 3D Waterfall views, for whichever channel is currently displayed. Color matches the same yellow/orange/red severity scheme as the on-device display.
  • Knob (firmware 3.10.0+): A CLIP indicator appears next to the temperature reading on every screen, with per-channel CLIP markers on the FFT / Equalizer view. See the Knob Guide for details.

The full system therefore gives you clip visibility on the WVC display, the RTC, the knob, and the AuralSync app simultaneously.

Per-Channel THD Analyzer (Pro 6 only)

The Pro 6 also includes a dedicated per-channel THD analyzer screen for inspecting a single channel in detail. From this screen you can switch between three sub-views of the same channel:

  • Spectrum: full-resolution frequency plot with the fundamental and harmonic peaks labeled.
  • Oscilloscope: time-domain waveform of the selected channel.
  • FFT bars: bar-style frequency display tuned for quick reading of the harmonic stack.

A settings panel on the same screen lets you adjust FFT size, smoothing, window type, and a Markers on/off toggle that hides the fundamental and harmonic reference lines on the spectrum view when you want a cleaner read of the raw signal.

Tap the arrow button at the top of any THD sub-view to expand the chart edge-to-edge in full-screen mode. The navigation arrows fade out after a moment of inactivity for an unobstructed chart and reappear on the next touch. Tap the arrow button again to restore the normal layout.

Tools Page (Pro 6 only)

Firmware 4.0.0 adds a Tools page to the WVC PRO-6 touchscreen with three sweep-based measurements. Each one builds a response curve in real time as you play a sweeping test tone into the input:

  • Frequency Response: shows how evenly the signal level holds across the frequency range, so you can spot rolloff or peaks.
  • Distortion vs Frequency: shows how harmonic distortion changes across the frequency range.
  • Crossover Detector: reveals where a crossover is rolling off a channel, useful for confirming high-pass and low-pass settings on a connected source or DSP.

Each tool has a channel selector, a Start/Stop button, and labeled frequency and level axes. To run a measurement, select the channel, press Start, and play a sweeping tone (for example, a sine sweep from the AuralSync app Tone Generator) into that input. The curve fills in as the sweep progresses. Press Stop to hold the result.

Note (firmware 4.1.0): The vertical (level) axis on each sweep tool now auto-scales to fit the captured data, so the response curve always fills the chart for easy reading. Re-opening a tool also starts a fresh measurement with a blank chart, instead of showing the previous capture.

Interpreting the FFT Display

When a test tone or music signal is passing through the unit, the FFT view shows:

  • The fundamental frequency as the dominant peak
  • Harmonics as smaller peaks at multiples of the fundamental frequency
  • THD (Total Harmonic Distortion) percentage calculated from the harmonic content Example: If you see the primary signal at 1 kHz and significant peaks at 2 kHz, 3 kHz, and 4 kHz, the signal has measurable harmonic distortion. A clean signal will show only the fundamental with harmonics well below -100 dB.

The WVC-PRO's onboard FFT analysis has been benchmarked against a professional audio analyzer (Quant Asylum QA403) and produces comparable THD readings, making it a practical tool for diagnosing signal quality issues in the field without additional equipment.

Interpreting the Oscilloscope Display

The oscilloscope view shows the waveform shape over time:

  • A smooth, symmetrical sine wave indicates a clean signal
  • A flat-topped waveform indicates hard clipping. The signal is being driven beyond its maximum level
  • An irregular or asymmetrical waveform may indicate soft clipping, dynamic distortion, or a poor-quality source

The oscilloscope displays real voltage values on the Y-axis, so you can see the actual signal amplitude for each channel. This makes it easy to verify output levels and compare channels at a glance.

On the WVC PRO-6 touchscreen, firmware 4.0.0 makes this view interactive: zoom, drag to pan and move the trace, and freeze it to inspect a moment closely (see the Oscilloscope View section above). The trace itself is also smoother and more stable.

Reducing the volume on your head unit or radio will clean up a clipped waveform. Once the signal is clean in the oscilloscope view, it is safe to pass to your amplifiers.

Accessing the Analysis Screens

Analysis screens are accessible directly from the WVC-PRO base unit display:

  1. From the main menu, navigate to the oscilloscope / analysis screens.
  2. Select the desired view: Oscilloscope, FFT, or Real-Time FFT (multi-channel).
  3. All views update in real time as signal passes through the unit.

    Availability: Signal analysis screens are available on WVC PRO and WVC PRO-6 with current firmware. See the Firmware Updates article for OTA update instructions.

3D Waterfall View

A rolling time-vs-frequency "mountain range" view is available on the RTC (firmware 3.9.7+) and on the WVC PRO-6 daughtercard 6-panel waterfall grid (firmware 3.9.7+). The waterfall plots the FFT spectrum over time, building a 3D landscape where peaks rise and fall as the music plays. This makes it easy to see sustained tones, transient peaks, and the evolution of bass content over time.

On the RTC, a single channel's waterfall fills the screen. On the WVC PRO-6 daughtercard grid, all six channels are tiled so you can watch the entire system at once.

Per-Channel Analysis

Each analysis view can be scoped to an individual channel, allowing you to isolate and inspect the signal on a specific RCA output. On the WVC-PRO 6-channel, all six channels are available for real-time FFT, oscilloscope, and THD analysis.

Future Integration with Intelligent Drive System (IDS)

Planned firmware updates will allow the signal analysis engine to integrate directly with the Intelligent Drive System. When enabled, the WVC-PRO will be able to:

  • Automatically reduce volume when THD exceeds a configured threshold
  • Mute the system when hard clipping, soft clipping, or excessive harmonic distortion is detected
  • Protect amplifiers and drivers from sustained distorted signal input This will allow the unit to respond intelligently to signal quality, not just voltage and temperature, as part of a fully automated protection system.