100 Things #44: Using Equalization Curves For Calibrated Measurements

Equalization curves are essential for creating flat frequency responses from speakers, allowing for them to be used as reliable references for testing devices like microphones. SoundCheck has functionality integrated directly into the calibration editor. From a single window, SoundCheck can measure and apply an equalization curve to your device, for use in any testing application.

Using Equalization Curves For Calibrated Measurements

Learn More About Equalizing Curves in SoundCheck

View more detailed tutorials on how to use this functionality. (In the Calibration section)

Read our knowledgebase article on how to apply equalization to an artificial mouth for a flat response.

 

Video Script: Using Equalization Curves For Calibrated Measurements

Did you know you can easily create an equalization curve for a speaker in SoundCheck? This works with loudspeakers, speakers in smart devices, headphones, telecommunication devices, and anything else you might want to equalize .

An equalization curve is used to modify the stimulus waveform before it is played out of a source speaker or mouth simulator. By compensating for a speaker’s non-linear magnitude and phase response on a per-frequency basis, a near flat frequency response from the speaker can be achieved. This allows the speaker to be used as a reliable reference across a specified frequency range in a test sequence most often used in the testing of microphones. In SoundCheck, this adjustment is made to the stimulus waveform before it is played during the acquisition step.

Creating an equalization curve for your device is simple with SoundCheck. In the output tab of the calibration editor, there is a set of sequences available. The Speaker Equalization sequence will provide a simple step by step process to create an EQ curve in seconds. Select the signal path you will be using in your test, then your Output Calibrated Device to have the EQ curve linked with. Once this sequence is complete, the EQ curve is stored in the selected Output Calibrated Device file.

Alternatively, if you already have an EQ curve, you can import and use this curve through the memory list. In the output tab of the calibration editor, select the option Copy From Memory List. The Import Calibration Data dialog box will allow you pick the source curve, the desired Output Calibrated Device, and will give the option to invert the curve if needed, right in the editor.

How do you use an EQ curve in SoundCheck? Simply put, anywhere you need! The stimulus editor features an EQ checkbox, which when enabled, will apply the equalization curve before the signal is output from the speaker during the Acquisition step. Since the EQ curve is tied to the Output Calibrated Device selected with the Signal Path, SoundCheck will automatically use the correct curve. Alternatively the EQ curve can be applied in the Signal Generator to equalize all of the available signal types, even when using a signal generator in a virtual instrument acquisition step.

SoundCheck is focused on giving audio test engineers every tool they may need, so no matter what device you are working with, we provide the right tools for the job.