User Interface Guide

This page describes the layout and components of the V-Listen main window. Understanding the interface structure will help you navigate the application efficiently and locate features quickly.

Main Window Layout

The V-Listen main window is divided into five primary regions:

Region	Position	Purpose
Start Menu / Toolbar	Top	Application commands: file operations, settings, help access
Left Navigation Panel	Left	Functional sections: Acquisition, Structure, Editor, Listening, Analysis
Workspace Area	Center	Tabbed workspaces for data display and interaction
Properties Panel	Right	Context-sensitive settings for the selected item or analysis
Bottom Bar	Bottom	Recorder controls, status indicators, and progress feedback

Start Menu and Toolbar

The top bar provides quick access to the most common operations:

File Operations

Load HDF — Open an existing HDF recording file for analysis.
Import FRF — Import pre-computed Frequency Response Functions from UFF/UNV files for modal analysis workflows.
Save Workspace — Persist the current layout, loaded data, and analysis configurations to a workspace file.
Export — Export results as CSV data or PNG images.

View Controls

Zoom to Fit — Reset all plot axes to show the full data range.
Toggle Grid — Show or hide the background grid on all plots.
Theme — Switch between light and dark display themes.

Help and Settings

Help (F1) — Open the V-Listen help system in a browser window.
Settings — Open the application settings dialog for paths, defaults, and hardware configuration.
About — Display version information, license status, and system diagnostics.

Left Navigation Panel

The left panel organizes all major features into collapsible sections. Click a section header to expand or collapse it. The active section is highlighted with a teal accent bar.

Acquisition

The Acquisition section controls live data capture from connected hardware frontends.

Element	Description
Frontend Selector	Drop-down list of detected hardware devices (NI DAQ and other supported frontends). Select the device to use for the current recording session.
Channel Configuration	Configure input channels: enable/disable individual channels, set coupling (AC/DC/ICP), input range, and sensitivity.
Sample Rate	Set the acquisition sample rate. Available rates depend on the connected hardware and number of active channels.
Trigger Settings	Configure start/stop triggers: manual, level-based, or external trigger input.
Recording Duration	Set a fixed recording duration or choose continuous recording mode.

Structure

The Structure section manages geometry models and test point definitions for structural dynamics analysis (EMA, OMA, ODS).

Import Geometry — Load STL mesh files for 3D structural visualization.
Measurement Points — Define, edit, and label test points on the geometry. Points are linked to recording channels for animated deflection shape display.
Coordinate System — Set the reference coordinate system and transformation for imported geometry.
Status Bar — Shows real-time status during geometry import: file name, vertex/triangle count, and processing progress.

Editor

The Editor section provides tools for modifying and conditioning recorded signals before analysis:

Channel Properties — View and edit metadata: channel name, physical quantity, engineering unit, and calibration factor.
Calibration — Apply sensitivity calibration using pistonphone reference levels or user-defined correction factors.
Signal Conditioning — Apply highpass, lowpass, or bandpass filters. Preview the filtered waveform before committing changes.
Windowing — Select and apply time windows (cut, crop) to isolate specific segments of a recording.

Listening

The Listening section enables audio playback of recorded signals for subjective evaluation:

Playback Controls — Play, pause, stop, and loop through selected channels. Playback position is synchronized with the Data Viewer cursor.
Output Device — Select the audio output device (system speakers, headphones, external audio interface).
A/B Comparison — Switch between two channels or processing states for rapid subjective comparison.
Playback Filters — Apply real-time A-weighting, bandpass filtering, or gain adjustment during playback.

Analysis

The Analysis section provides access to all analysis engines, organized by category:

Category	Available Analyses
Spectral	FFT, FFT vs. Time, 1/n-Octave Band, PSD, Cross-Spectrum, Coherence, Transfer Function
Order	Order Spectrum, Order vs. RPM, Overall Level vs. RPM, Campbell Diagram
Psychoacoustics	Loudness, Specific Loudness, Sharpness, Roughness, Fluctuation Strength, Tonality (PR/TNR), Articulation Index
Structural	FRF Measurement, Modal Parameter Extraction, ODS Animation, MAC Matrix
Diagnostics	Envelope Analysis, Cepstrum, Bearing Fault Detection
Sound Power	ISO 3741, ISO 3744, ISO 3745

Clicking an analysis type loads its parameter controls into the Properties Panel on the right. The analysis runs on whichever channels are currently selected in the Data Viewer.

Workspace Area

The central workspace area uses a tabbed interface. Multiple workspace tabs can be open simultaneously, and you can switch between them by clicking their tab headers. The following workspace types are available:

Pool

The Pool workspace displays all loaded data files and their contents in a hierarchical tree view. Each HDF file expands to show its constituent channels with metadata (name, sample rate, duration, physical quantity, calibration status). The Pool serves as the central data inventory for your session.

Double-click a channel to open it in a new Data Viewer tab.
Right-click for context menu options: Add to Data Viewer, Properties, Remove.
Drag channels from the Pool directly into an existing Data Viewer for quick overlay.

Data Viewer

The Data Viewer is the primary visualization workspace. It displays time-domain waveforms, frequency spectra, spectrograms, order maps, and all other analysis result types as interactive plots.

Feature	Description
Multiple Plots	A single Data Viewer tab can contain multiple stacked or tiled plots, each showing different channels or analysis results.
Cursor Readout	Click anywhere on a plot to place a cursor. The exact X/Y values at the cursor position are shown in the footer bar below the plot.
Linked Axes	Time axes are linked across all plots in the same Data Viewer tab. Zooming or panning one plot automatically adjusts all others.
Color Maps	Spectrogram and heatmap plots use configurable color maps. Right-click the color bar to change the palette or adjust the dynamic range.
Legend	Each plotted curve is labeled with its source channel and analysis type. Click legend entries to show/hide individual curves.

Mark Analyzer

The Mark Analyzer workspace allows you to define time markers and regions on the waveform, then compute statistics (RMS, peak, crest factor) and run analyses on each marked segment independently. This is useful for comparing different operating conditions within a single recording.

Recorder

The Recorder workspace provides a dedicated view for live data acquisition. It displays real-time waveforms from all active channels, level meters, and overload indicators. The Recorder workspace is automatically activated when a hardware frontend is connected and acquisition is started.

Properties Panel

The Properties Panel on the right side of the window displays context-sensitive settings. Its content changes depending on what is currently selected:

Channel selected in Pool: Shows channel metadata (name, unit, sample rate, calibration).
Analysis type selected: Shows all configurable parameters for that analysis (window function, FFT size, overlap, frequency range, weighting, averaging mode).
Plot selected in Data Viewer: Shows display settings (axis range, scale type, color map, line style).
Geometry node selected: Shows coordinates, labels, and channel assignments for the selected measurement point.

Tip: Hover over any parameter label in the Properties Panel to see a tooltip with a description of the parameter, its valid range, and the default value.

Bottom Bar

The bottom bar spans the full width of the application window and contains the following elements:

Recorder Controls

When a hardware frontend is connected, the bottom bar displays transport controls for data acquisition:

Control	Function
Record	Start recording data from all active channels to an HDF file.
Stop	Stop the current recording. The file is finalized and added to the Pool.
Monitor	Stream live data for preview without writing to disk.
Level Meters	Real-time peak and RMS level bars for each active channel, with overload (clipping) indicators.

Status Indicators

Hardware Status: Shows the connected frontend name and connection quality. Green indicates a stable connection; yellow indicates intermittent communication.
Processing Status: Displays a progress bar and elapsed time during long-running analysis operations.
Memory Usage: Shows current application memory consumption as a visual indicator to help you manage system resources.

Keyboard Shortcuts

The following keyboard shortcuts are available throughout the application:

Shortcut	Action
`Ctrl+O`	Open / Load HDF file
`Ctrl+S`	Save workspace
`F1`	Open help system
`F5`	Run / recalculate selected analysis
`Ctrl+A`	Select all channels in the Pool
`Delete`	Remove selected item from the Data Viewer
`Home`	Zoom to fit (reset axes to full range)
`Space`	Play / pause audio playback (Listening section)
`Escape`	Cancel the current operation or close a dialog

Next step: Now that you understand the interface, return to the Quick Start Guide to begin working with real data, or browse the full help index for detailed documentation on specific analysis types.