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Signal Analysis Features

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Overview

The WVC-PRO and 6-channel WVC-PRO both include 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.

The 6-channel WVC-PRO has an additional touchscreen on the unit itself, so its analysis views can be inspected directly on the device. The 2-channel WVC-PRO has no on-unit display, so the same data is delivered to the RTC, the wireless Knob, and the LF Audio AuralSync app instead.

Feature Availability by Model

The signal analysis suite is split across two tiers: features that depend only on the audio analysis hardware (available on both 2-channel and 6-channel WVC-PRO), and features that require the 6-channel WVC-PRO's onboard touchscreen.

Feature 2-Channel WVC-PRO 6-Channel WVC-PRO
Oscilloscope view Via RTC, Knob, or AuralSync app On unit touchscreen, plus RTC, Knob, AuralSync app
FFT / Equalizer view Via RTC, Knob, or AuralSync app On unit touchscreen, plus RTC, Knob, AuralSync app
Real-Time multi-channel FFT grid Not applicable (stereo only) On unit touchscreen (3×2 grid of all six channels)
CLIP indicators (per channel) Via RTC, Knob, AuralSync app On unit touchscreen, plus RTC, Knob, AuralSync app
Clip Detection sensitivity setting Yes Yes
Per-Channel THD Analyzer Not available On unit touchscreen (channels 3-6 only)
Tools page (sweep-based measurements) Not available On unit touchscreen (channels 3-6 only)
3D Waterfall view Via RTC On unit touchscreen (6-panel grid) and RTC
Peak-frequency readout Via RTC, Knob, AuralSync app On unit touchscreen, plus RTC, Knob, AuralSync app

The two channels of the 2-channel WVC-PRO are analyzed on a stereo audio codec inside the unit. The 6-channel WVC-PRO uses a dedicated analysis processor that drives the touchscreen and runs the THD analyzer and sweep tools in addition to the basic views.

Available Analysis Screens

Oscilloscope View

Available on 2-channel WVC-PRO (via RTC, Knob, AuralSync app) and 6-channel WVC-PRO (on unit touchscreen, plus the same remote surfaces).

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

On the 2-channel WVC-PRO, the oscilloscope is viewed on the RTC, the Knob, or in the AuralSync app, since the unit has no on-board display.

Starting in firmware 4.0.0, the oscilloscope view on the 6-channel WVC-PRO 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

Available on 2-channel WVC-PRO (via RTC, Knob, AuralSync app) and 6-channel WVC-PRO (on unit touchscreen, plus the same remote surfaces).

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

On the 2-channel WVC-PRO, the FFT view is delivered to the RTC, the Knob, and the AuralSync app. On the 6-channel WVC-PRO, the same view is also rendered on the unit's touchscreen.

Real-Time Multi-Channel FFT Grid

Available on 6-channel WVC-PRO only.

This view shows the FFT spectrum across all six channels simultaneously, allowing you to monitor every connected amplifier input at once. On the unit's touchscreen, all six channels are arranged in a 3x2 grid so you can watch every input at a glance without switching screens. The 2-channel WVC-PRO does not have this grid view because it has only two channels and no on-unit display.

A CLIP indicator appears on any channel panel when clipping is detected on that input. Starting in firmware 3.10.0, every connected channel reports clipping individually. 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 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 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. It has four levels, from least sensitive to most sensitive:

Off

Clip detection is disabled entirely. No CLIP indicator appears on the WVC touchscreen, the RTC, the wireless knob, or the AuralSync app, regardless of what your input signal is doing. No per-channel clip data is sent to any display surface.

  • Use when: You are doing bench measurements, you want a clean uncluttered display for a show, or you have a known-clean signal chain and do not want any clip annotations.
  • Trade-off: You lose all warning of real clipping. Sustained clipping can damage speakers and amplifier input stages, so leaving the system on Off for normal listening is not recommended.

Low (default)

The most conservative active setting. Only clear, obvious clipping is flagged. The detector is biased toward staying silent unless the signal is unambiguously saturated, even briefly.

  • Use when: You want clip detection on as a safety net but do not want the indicator lighting up during loud-but-clean music, deep sub-bass content, or aggressive but un-clipped bass-boost material.
  • What you'll see: Hard clipping (the classic flat-topped waveform) is caught reliably. Mild or borderline clipping events will usually not trigger the indicator.

Medium

The historical default tuning shipped with earlier firmware. A balanced setting that flags both clear clipping and moderate clipping that is just past the threshold of audible distortion.

  • Use when: You want a useful middle ground for daily listening on systems you do not know intimately, or when tuning a new install.
  • What you'll see: Hard clipping is caught immediately, and the indicator will also light on moderate clipping events that a careful listener would notice as audible distortion.

High

The most sensitive setting. Catches subtle soft-clipping and codec saturation in music (compressed sources that arrive with their dynamic range already crushed), as well as everything the lower levels catch.

  • Use when: You are using the WVC as a tuning tool to track down even brief clipping events, you are running a sensitive measurement, or your install includes delicate components (high-frequency drivers, ribbon tweeters) where any clipping is unacceptable.
  • What you'll see: Almost every clipping event will register, including transient peaks during loud passages and codec-driven distortion in heavily-compressed source material. Some users find this setting too eager for everyday listening; if so, drop back to Medium or Low.
Tip

If you are not sure where to start, leave the setting at Low. It catches the dangerous cases (hard clipping that can damage speakers) without complaining about loud-but-clean playback. Move to Medium or High only if you specifically want to see softer or briefer clipping events.

Change the setting from the 6-channel WVC-PRO touchscreen (Settings → Options tab → Clip Detection), from the Knob (press and hold the knob to open the menu, then Base Settings → Clip Detection; requires Knob firmware 4.1.0 or newer paired with a WVC-PRO or WVC-PRO 6 base on firmware 4.1.0 or newer), or from the AuralSync app. The setting is supported on both the 2-channel and 6-channel WVC-PRO. On the 2-channel unit, change it from the Knob or the AuralSync app, since the unit itself has no touchscreen. Whichever surface you change it on, the new value syncs to the others. Clip detection is a PRO-only signal-analysis feature and is not available on the WVC-LITE.

Starting in firmware 4.0.0, every channel panel on the 6-channel WVC-PRO touchscreen 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

Available on 2-channel WVC-PRO and 6-channel WVC-PRO.

Per-channel clip information is streamed to remote displays so the indicator is visible everywhere the system reaches, regardless of which model you have:

  • 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. Per-channel CLIP reporting at this resolution requires both the Controller and the RTC to be on 3.10.5 or newer; older firmware versions can show a system-wide CLIP signal but not the per-channel pill.
  • 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.

On the 6-channel WVC-PRO, clip indicators also appear on the unit touchscreen, so you get clip visibility on the unit itself, the RTC, the Knob, and the AuralSync app simultaneously. On the 2-channel WVC-PRO, clip indicators are visible on the RTC, the Knob, and the AuralSync app.

Per-Channel THD Analyzer

Available on 6-channel WVC-PRO only (on the unit touchscreen). Limited to channels 3-6.

The 6-channel WVC-PRO also includes a dedicated per-channel THD analyzer screen on its touchscreen for inspecting a single channel in detail. The THD analyzer is driven by the analysis processor inside the unit's touchscreen module, which is wired to channels 3, 4, 5, and 6 only. Channels 1 and 2 are processed elsewhere in the unit and are not selectable on the THD analyzer screen; use the FFT, oscilloscope, or Real-Time Multi-Channel FFT Grid views to inspect channels 1 and 2. The 2-channel WVC-PRO does not have this screen at all.

From the THD analyzer 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

Available on 6-channel WVC-PRO only (on the unit touchscreen). Limited to channels 3-6.

Firmware 4.0.0 adds a Tools page to the 6-channel WVC-PRO 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. Like the THD analyzer, the Tools page is driven by the unit's touchscreen analysis processor, so the channel selector inside each tool offers channels 3, 4, 5, and 6 only. To run sweep measurements on channels 1 or 2, route the source signal into one of channels 3-6 for the measurement. The 2-channel WVC-PRO does not have the Tools page, since it has no on-unit display.

  • 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.

Note (firmware 4.1.1): The Distortion vs Frequency tool's distortion axis now starts at a fine 1% scale and zooms out only as far as the measurement needs, so typical low-distortion sweeps show much more detail.

Planned (upcoming release): Each sweep tool will let the measurement settle for a moment after you press Start before it begins plotting, so the curve reads accurately from the first point instead of briefly showing an inflated value. A short Settling... message will appear during this window. The Distortion vs Frequency tool will cover 40 Hz to 20 kHz, the range where its distortion readings are reliable. Confirm the exact version on help.lf-audio.com/firmware-updates once it ships.

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 6-channel WVC-PRO 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

On the 6-Channel WVC-PRO

The unit has a touchscreen on the side of the chassis, so you can read the analysis views directly on the unit:

  1. From the main menu, navigate to the oscilloscope / analysis screens.
  2. Select the desired view: Oscilloscope, FFT, Real-Time Multi-Channel FFT Grid, THD Analyzer (channels 3-6 only), or Tools (channels 3-6 only).
  3. All views update in real time as signal passes through the unit.

On the 2-Channel WVC-PRO

The 2-channel unit has no on-board display. Use one of the connected accessories to view its analysis data:

  • RTC: Mount in the cabin and swipe between the oscilloscope, FFT, FFT Hi-Res, and 3D Waterfall views.
  • Wireless Knob (Single, Dual, Concentric, or Quad): Open the FFT / Equalizer and Oscilloscope screens from the knob menu.
  • AuralSync app: View the same data on your phone over Bluetooth.

Availability: Signal analysis hardware is included with both the 2-channel WVC-PRO and the 6-channel WVC-PRO with current firmware. The WVC-LITE does not include signal analysis hardware. See the Firmware Updates article for OTA update instructions.

3D Waterfall View

Available on 2-channel WVC-PRO (via RTC) and 6-channel WVC-PRO (on unit touchscreen and RTC).

A rolling time-vs-frequency "mountain range" view that 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 (firmware 3.9.7+), available with both 2-channel and 6-channel WVC-PRO: a single channel's waterfall fills the screen. Swipe to switch channels.
  • On the 6-channel WVC-PRO touchscreen (firmware 3.9.7+): all six channels are tiled in a 6-panel grid so you can watch the entire system at once.

The 2-channel WVC-PRO does not have an on-unit waterfall view (no on-board display), so view this on the connected RTC.

Per-Channel Analysis

Each analysis view can be scoped to an individual channel so you can isolate and inspect the signal on a specific RCA output:

  • 2-channel WVC-PRO: two channels (Left and Right) are available for FFT and oscilloscope analysis.
  • 6-channel WVC-PRO: all six channels are available for FFT, oscilloscope, multi-channel FFT grid, 3D waterfall, and CLIP indication. The Per-Channel THD Analyzer and Tools page (sweep-based measurements) are limited to channels 3-6, since those tools are driven by the analysis processor in the unit's touchscreen module. Channels 1 and 2 are inspected with the standard FFT and oscilloscope views.

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.