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The SoundCheck® system from Listen includes everything you need to perform sound quality audio measurements on a wide range of devices – the software, the audio interface, other test interfaces and accessories, and test sequences.

The system is centred around the SoundCheck software. This powerful package controls and communicates with the measurement hardware, and includes all the stimuli, algorithms and analysis functionality needed to develop and run virtually any electroacoustic or audio electronic test. It is paired with hardware ranging from a simple, all-in-one audio test box to sophisticated discrete components for a complete test system. In addition to Listen hardware, a range of 3rd party products and test accessories are fully supported within SoundCheck.

The modular software and many hardware options enable a customized solution to be configured for your specific test requirements and budget. Annual software updates ensure that the system evolves to keep pace with evolving test methods and requirements, and both software and hardware can be expanded at any time to meet future testing needs.

SoundCheck Software is the heart of a SoundCheck test system. It generates all the test signals, performs analysis and displays results according to the user’s configuration.

While it is an extremely powerful and flexible product, its capabilities can be described in 3 parts:

  • Test Sequences – how tests are configured by the operator
  • Virtual Instruments – software implementation of standard audio test equipment
  • Data Analysis – the various analyses that SoundCheck can perform on your data

SoundCheck truly is the most flexible audio and audio electronic test system available. Its measurement capabilities include:

Frequency Response
SoundCheck offers many options for measuring frequency response across various applications. Simple sine sweeps are used to test basic transducers, providing an optimal signal to noise ratio by analyzing the signal with high precision filters. For more complex scenarios SoundCheck’s Real-Time Analyzer can be used to measure frequency response with broadband stimulus signals such as speech. Transfer function analysis allows for direct input versus output comparison and is very useful in electronics testing. Customers who need to test open air rather than in an anechoic chamber can take advantage of SoundCheck’s sophisticated Time Selective Response module for performing simulated free field measurements.

No single distortion measurement can characterize a device or detect all possible manufacturing defects, so SoundCheck includes a complete set of distortion algorithms to suit every requirement. These range from traditional measurements like THD, Rub & Buzz and Intermodulation to cutting edge perceptual distortion metrics. Many of these measurements can be calculated from a single sine sweep, providing superior accuracy alongside minimal test times. Distortion measurements include Harmonic Distortion (THD, THD+N), Rub & Buzz, Loose Particle Detection, Intermodulation Distortion, Non-coherent Distortion and Perceptual Distortion Measurement

Phase (polarity)
Phase is an important audio test component. SoundCheck allows accurate measurements of the DUT’s phase response when measuring with sine waves, or relative phase using transfer function analysis. It can also calculate phase-derived measurements such as polarity and group delay.

Polar Plot
SoundCheck measures a device’s directional characteristics by acquiring data at different angles either manually or via an automated turntable. Directional data can then be displayed on a polar plot and used to calculate the directivity index.

Thiele-Small Parameters
SoundCheck features pre-programmed Thiele-Small equations and test sequences for the three commonly-used methods: added mass, known volume and known driver mass. A simple curve fit algorithm automatically extracts the F0, Q and Z-max values, and the standard Thiele-Small equation can be adapted using the post-processing equation editor for analysis using different models

Time-Frequency Analysis
Detailed signal analysis is carried out simultaneously in both the time and frequency domain, which is ideal for impulse response analysis and detection of loose particles and Rub & Buzz in loudspeakers. Time-frequency analyses are also valuable for identification of transient effects such as drop out in digital devices including VoIP and Blue¬tooth headsets. SoundCheck’s Time-Frequency analysis options include Waterfall plots /Cumulative spectral decay (CSD), Wigner-Ville, Short term fourier transform (STFT) and Wavelet analyses.

SoundCheck can measure the electrical impedance of loudspeakers and headphones using a simple reference resistor (included in Listen hardware such as AmpConnect and SC Amp) or using an even higher-accuracy two-channel measurement. Resonance characteristics such as Q, Zmax and F0 can also be derived from the impedance curve.

Measure to International Standards
SoundCheck tests devices to many international standards. Pre-written test sequences are available for TIA 810A, TIA 920B, ANSI/IEC Hearing Aid standards, Lync/Skype testing, Hearing Aid Compatibility (HAC) and EN-50332 (Max SPL of portable devices), and more.

Detailed technical capabilities of SoundCheck.

SoundCheck 19 Technical Specifications

SoundCheck Virtual Audio Test Bench

  • Run multiple instances of each virtual instrument simultaneously
  • Save to Memory List available in all meters

Manual Signal Generator

  • Sine
  • Pink and White Noise with user-defined frequency range
  • Streaming .wav file from disk with RMS, Peak level and active speech level calibration
  • Equalization using calibration measurements or any user-defined curve


  • AC RMS, AC Peak and DC levels (Average, Max Hold, Min Hold) with overload indication
  • Linear and Continuous-Moving averaging time (fast, slow, and user-defined)
  • Linear and Exponential averaging time (Fast, Slow, and user-defined)
  • A, B, C and user-defined weightings
  • Selectable Max/Min limits with Pass/Fail indication
  • Save and Recall specific multimeter settings
  • Fixed or auto-tracking bandpass filter option
  • ‘Linear Repeating’ averaging mode


  • Triggering
  • Delta cursor
  • Selectable graphical zoom
  • View spectrum of current waveform

Spectrum Analyzer

  • FFT with arbitrary number of spectral lines (only limited by computer speed and memory)
  • Hanning, Hamming, Blackman-Harris, Exact Blackman, Blackman, Flat top, 4 Term Blackman-Harris, and 7 Term Blackman-Harris windows
  • Triggering
  • Complex or power averaging
  • Average, Maximum, Minimum level with overload and real time indicators
  • Selectable averaging time (Linear & Exponential)
  • A, B, C and user-defined weightings
  • Pure tone frequency and amplitude extraction with “snap to max”
  • Delta and Harmonic cursor with THD readout
  • Selectable graphical zoom
  • View last waveform of current spectrum
  • Save to memory of current spectrum

Real-Time Analyzer

  • 1/1, 1/3, 1/6, 1/12, 1/24 octave filters with true digital recursive filters
  • Average, Maximum, Minimum level with overload and real time indicators
  • A, B, C and user defined weighting filters
  • Complies with ANSI S1.11 and IEC 1260
  • Linear and Exponential averaging time (Fast, Slow, and user-defined)

Real Time Distortion Analyzer

  • Continuous real time measurement of output distortion
  • Select THD / THD+N, THD / THD+N Residual and SINAD
  • A, B, and C weighting filters along with user-defined arbitrary weighting functions
  • Distortion over time using optional strip chart recorder

Frequency Counter

  • High resolution frequency measurement
  • Frequency value can be saved to the memory list for use in a sequence

Strip Chart Recorder

  • Provides measurement over time capability for the multimeter, distortion analyzer and frequency counter
  • Plot continuously or for a predefined amount of time and plot instantaneous results or repeating averages
  • Curves and Values can be saved to the memory list for use in a sequence

SoundCheck Step Editors


  • Windows Multimedia devices including sound cards with WASAPI drivers, ASIO drivers (PCI, PCMCIA, USB, Fire wire), Bluetooth, and VoIP.
  • Apple’s Core Audio devices (SoundCheck Mac version)
  • NI DAQmx data acquisition cards including NI 4461
  • Calibration and settings including sampling rate, bit depth, analog or digital audio, maximum voltage, and alias free frequency limit.
  • I/O cards for TTL relay control
  • Computer interfaces control with RS-232, GPIB (IEEE-488), footswitch and buzzer.
  • Configuration for AmpConnect™, AudioConnect™, AudioConnect 4×4™, SoundConnect 2™ , DC Connect™,  BTC -4148 and BQC-4148
  • Multichannel configuration with table view of channels


  • Measure Input and Output sensitivities for transducers, amplifiers, and signal conditioning devices using built-in routines and store calibration history
  • Calibration with external, absolute source including acoustic, vibration, or voltage.
  • User-defined physical units (e.g. Pa, V, G, etc.)
  • Complex Equalization (amplitude and phase) of input and output devices (e.g. microphones and amplifiers). If the output device is an acoustic source, (e.g. loudspeaker, mouth simulator), SoundCheck can automatically equalize any test signal including arbitrary signals.
  • Import of EQ/Correction curves for transducers


  • Message steps initiated based on Pass/Fail conditions
  • Display text message in local language, input numeric values, Yes/No dialog
  • Digital I/O
  • IEEE-488 and RS-232
  • AmpConnect™, AudioConnect™, AudioConnect 4×4™ , SoundConnect 2™ , DC Connect™ BTC-4148 and BQC-4148 setup


  • Log sweep (“Farina” sweep)
  • Sine (stepped – any linear or logarithmic resolution, and amplitude sweep)
  • Two-tone (two sweeping tones for Difference Frequency Distortion or one fixed and one sweeping tone for IM)
  • Multitone with linear or logarithmic spacing
  • Noise (pink, white, MLS with user-defined bandpass range)
  • Arbitrary (any WAV file)
  • Equalization
  • DC (requires Listen DC Connect or National Instruments hardware)
  • Sweep Equalization for Minimized Transients – Selecting equalization enables a smooth transition between steps in stepped sine amplitude and frequency sweeps


  • Play & Record, or any combination of Signal Generator, Multimeter, RTA, and FFT
  • Capture response time waveform as a WAV file
  • Simultaneous acquisition using up to 64 channels
  • Triggered record
    • Level and frequency
    • Level and cross-correlation
  • Record level monitoring


  • Save to SC binary .dat, .res and .wfm formats
  • WAV
  • ASCII text
  • MS Excel
  • MS Access & SQL databases



  • Impulse Response
  • Auto-Correlation
  • Cross-Correlation
  • Time Envelope
  • Loose particle detection
  • Automatic delay compensation


  • FFT & DFT (any size), and Nth octave resolution
  • Hann, Blackman-Harris and Flat Top windows
  • Auto-spectrum & Cross-spectrum
  • Spectral Scaling: RMS or Power Density
  • Frequency and phase response including harmonics
  • Complex or power averaging
  • Relative or absolute response
  • Coherent Output Power
  • Coherence & Non-Coherence
  • Signal-to-Noise Ratio
  • Measurement Confidence
  • Impedance


  • Broadband RMS to measure the unfiltered level of an AC or DC signal
  • Average FFT Spectrum
  • Time Selective Response (‘Farina” method) to measure free-field and impulse response of fundamental AND harmonics. This includes deconvolved time response and choice of time windows.
  • Heterodyne to measure frequency and phase response with optimal accuracy
  • HarmonicTrak™ Algorithm tracks level and phase of any user-selected harmonics including sub-harmonics or intermodulation products; no limit to number of harmonics
  • Loose particle detection
  • Multitone
  • RTA Spectrum & frequency response
  • Transfer function between any two channels


  • THD and Rub & Buzz
  • Normalized THD and Rub & Buzz distortion (harmonics compared to amplitude of fundamental at the measured frequency)
  • Perceptual Rub & Buzz in phons
  • THD + Noise
  • Intermodulation or Difference Frequency
  • Difference Frequency
  • Non-Coherent Distortion


  • Automatically recall data or results


  • Complex math: Addition, subtraction, multiplication, division, offset by constant (X, Y, or Z dimensions), change sign, reciprocal, absolute value, square, square root, exponential, and logarithm
  • Scalar (Ave, Power, Max, Min, Resonant Frequency, Q, Notch, Loudness)
  • Windowing (time and frequency)
  • User-defined Equations (e.g. Thiele-Small parameters)
  • Change resolution to Nth octave or user-defined linear or logarithmic
  • Nth Octave synthesis
  • Power Summation of any user-defined frequency range
  • Group delay
  • Unwrapped phase
  • Search range to find the intersection of two curves (e.g. -3dB points of crossover network)
  • Curve smoothing with 1/3, 1/6, 1/12, and 1/24 octave or user-defined linear or log resolution
  • Average Curve
  • Loudness rating according to IEEE and ITU-T; example sequences for TIA and other industry standards included
    Attack & Release time calculates the time for the response signal to rise or decay, respectively, by a user-defined amplitude in dB or linear units
  • Directivity Index
  • Resampling and sampling rate correction
  • FFT / Inverse FFT
  • Zwicker loudness (level and spectrum)
  • Standard & arbitrary waveform filtering
  • Active speech level (ITU-T P.56)


  • Average
  • Max, Min, Mean
  • Standard Deviation with user-defined sigma
  • Process Control (Cp & Cpk)
  • Best and Worst Fit to Average with ranking
  • Yield
  • Histogram and bell curve fit


  • Pass/Fail
  • Absolute
  • Floating (x & y directions)
  • Aligned to a pre-defined value (e.g. 0 dB at 1 kHz)
  • Dynamic, using live measurements
  • Waveforms, single values, and curves
  • Control of significant digits
  • Margin, Critical and Failed points


  • Multiple displays on separate tabs allow viewing of curves, single values, and test results with PASS/FAIL indicators; display layout can be transferred to Word or as HTML document; curves with different units (e.g. dBSPL and Ohms) can be displayed in one graph with no limit to number of curves displayed in a single graph; data from any one graph can be exported directly to a new Excel file or a pre-defined template
  • Displays include XY graph, table, results, text, polar plots and embedded images
  • Default template and duplicate
  • Save to image file
  • Lock display to protect display layout
  • Data search function


  • Report generation to Excel, Word, HTML or image files
  • Use of templates (Excel, Word)
  • Print preview
  • Direct print to file or printer
  • Automatic file naming

Custom Steps
Outline ET250-3D Turntable Control

  • Ethernet control for the Outline ET250-3D turntable

Instrument Open Close

  • Template for creating a custom step combining your LabVIEW code with SoundCheck virtual instruments

System Custom Step

  • Run Command Line operations as part of a sequence

Mixer Volume

  • Control input/output levels of a 2 channel WDM / Core Audio device

RS232 Read Integer

  • Programming example that reads the integer value from an external RS232 device

Serial Number Write Read

  • Programming example for creating a custom vi to read or write to the SoundCheck serial number field

Open Before Converting Old Custom VIs

  • Tool for updating your Custom VIs to the latest version of SoundCheck / LabVIEW

To see the SoundCheck brochure click here

To see the SoundCheck automotive datasheet click here

To see the SoundCheck headphone datasheet click here

To see the SoundCheck loudspeaker datasheet click here

To see the SoundCheck Voice Controlled Audio Device datasheet click here

The new features in SoundCheck Version 19 Update