Tag Archive for: sequences

100 Things #36: Using Virtual Instruments for Greater Acquisition Flexibility

Virtual Instruments in SoundCheck are a quick and easy way to take a measurement without developing a full test sequence, for example to check a level in the multimeter or view an FFT spectrum in the Spectrum Analyzer. They also offer amazing versatility when used in a test sequence to acquire data for further analysis, post-processing, etc. Watch this short video to learn more.

Using Virtual Instruments in SoundCheck

Learn More About SoundCheck’s VIs

Check out our easy-to-follow tutorials on virtual instruments. (in the Acquisition section)

Watch our video on how to save time with virtual instrument configuration.

Check out our seminar on SoundCheck’s Virtual Instruments.


Video Script: Quick Measurements with Virtual Instruments

Virtual Instruments in SoundCheck are a quick and easy way to take a measurement without developing a full test sequence. This might be useful if, for example, you want to check a level in the multimeter or view an FFT spectrum in the Spectrum Analyzer. And, all of the measurements in SoundCheck meters can be saved to SoundCheck’s memory list.

However, did you also know that SoundCheck instruments can be used in a test sequence? A Virtual Instrument acquisition step can be created to acquire from a device you want to measure. This adds yet another way in SoundCheck to acquire data for further analysis, post-processing, etc.

You can even use multiple Instruments manually or in a virtual instrument acquisition step. Here’s an example of a virtual instrument acquisition step that acquires input from the reference mic and calculates the level and RTA spectrum [show screen capture of sequence]. Once acquired, the data can be processed like any other data in SoundCheck. For example, the level or RTA spectrum can be passed through a pass/fail limits step. This might be useful for measuring input-only noise, for example: fan noise from your product.

In this example, you can use a signal generator and mult-RTA in a Virtual Instrument acquisition to measure the individual channel of a 6-mic array along with the power sum of the 6 channels [screen capture of sequence]. The acquired data is captured to the curves tab of the memory list.

As you see, integrating virtual instruments as a step in SoundCheck is very easy, and another example of SoundCheck’s testing flexibility.



Measuring Hearing Protection Devices to ANSI S3.19-1974 Standard

This sequence is used to measure the NRR, or Noise Reduction Rating, of a hearing protection device to the ANSI S3.19-1974 standard. NRR is a numerical representation of the sound attenuation of a device. The sequence first measures the response spectrum of the unoccluded hearing protector test fixture, then makes a second measurement with the hearing protection DUT affixed. A signal generator virtual instrument generates the pink noise stimulus while an RTA virtual instrument simultaneously records the A and C weighted noise spectrums. The unoccluded and occluded measurements are analyzed with a series of post-processing steps according to the ANSI S3.19-1974 standard. The final display shows the NRR numerical value, RTA spectra of the left and right side of the unoccluded and occluded hearing test fixture, average attenuation level of the DUT, and the standard deviation of the DUT on the test fixture.


Measurement of Stereo Soundfield Parameters

The stereo soundfield sequence measures parameters such as Interaural level difference (ILD) and interaural cross-correlation (IACC) using a Head and Torso Simulator (HATS). The spectrum is measured at each ear and calculates interaural level differences (ILD), spectral balance, delay differences, and interaural cross-correlation (IACC). The measurements are made using different time windows, so that the direct, early, late or total parts are separated.

Several different signals are applied to the left and right inputs of the device under test (DUT), and the measurements are made with the HATS left and right ears. Up to 9 measurements in varying positions are made and saved. Results for each position are displayed, and on completion of the testing, means and standard deviations are shown.


TIA-5050 Test Sequence for Narrowband (NB) and Wideband (WB) Mobile Handset Phones

TIA 5050 is a US standard with measurement methods and requirements for the receive volume control performance of both narrowband (NB) and wideband (WB) mobile handset phones. The measurements include conversational gain, frequency response, and distortion. Measurements are made at both 2N and 8N handset application forces, with different requirements applied to each. Either Free Field (FF) or Diffuse Field (DF) can be chosen as the Listener Reference Point (LRP) for receive frequency response.


19: Exploring Custom Steps (working from home with SoundCheck)

Learn how to level-up your SoundCheck sequence using Custom Steps – LabVIEW VIs that can be used as steps in SoundCheck sequences to implement operations that cannot be done natively in SoundCheck. A selection of custom step templates built into SoundCheck accelerates the development of custom steps with examples that allow you to open and close virtual instruments, control turntables, read/write serial numbers and even open any .exe file such as a Python script. Devin Vaillancourt demonstrates how to use this powerful feature.

Example Sequences (Working from home with SoundCheck #6)

In this video, Steve Tatarunis shows where to find, and how to use, a selection of example test sequences included with your SoundCheck installation. These can save considerable amounts of time developing tests as you can start with one of these and modify it to meet your needs – certainly worth checking out if your plan for the next few weeks involves developing some new sequences or figuring out how to test a device!