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Bluetooth Headphone Testing

It’s easy to make comprehensive audio measurement on Bluetooth Headphones, headsets and hearables with SoundCheck. With the simple addition of a stand-alone Bluetooth interface to your existing test configuration, measurements can be made exactly the same way as your conventional wired headphones. Rather than the test signal being directly transmitted to the headphones via a cable, it is sent to the Bluetooth interface and transmitted to the headphones. Our Bluetooth interfaces are fully controlled by SoundCheck, therefore are easily used in test sequences. The SoundCheck software itself features advanced post-processing tools resampling and frequency shift to overcome the Bluetooth time delay and precisely synchronize the stimulus and response waveforms prior to analysis. This makes it easy to compare wired and Bluetooth measurements, as well as measure Bluetooth headset microphones, analyze Bluetooth dropout, compare measurements with different Bluetooth protocols and more.

 

Example configuration for Bluetooth Headphone Test:

This short video demonstrates how easy it is to add Bluetooth headphone measurements to your test system:

 


We also offer a much more in-depth demonstration of Bluetooth headphone testing in this recorded seminar, along with a detailed comparison of our Bluetooth interfaces.

 


To get our SoundCheck users up and running quickly with Bluetooth measurements, we offer a free Bluetooth headphone test sequence which tests the send and receive performance of a stereo Bluetooth headset with a built-in microphone using a mixture of analog and digital channels. This sequence may be used as-is, or can be used as a starting point for your own test development and customized to meet your needs. Naturally Bluetooth measurements can be combined with other specific headphone measurements, such as ANC measurement by simply adding the Bluetooth interface to the test configuration, and inserting the appropriate steps in the test sequence.

 

Practical Measurement of Bluetooth and Lightning Headphones

Author: Daniel Knighten.  Reprinted from the July 2017 issue of Voice Coil.

In this article, Dan Knighten discusses how to overcome the challenges of measuring headphones with wireless and digital interfaces such as Bluetooth, Lightning and USB-C to make the same measurements as on conventional wired headphones.

Full Article

 

Bluetooth Headset Measurement

This sequence tests the send and receive performance of a stereo Bluetooth headset with a built-in microphone using a mixture of analog and digital channels. The left and right earphones are measured simultaneously with a stepped sweep from 20kHz to 20 Hz using two Bluetooth profiles: A2DP and HFP. The mic is measured with a stepped sweep from 8kHz to 100Hz using the HFP profile.

A short 1kHz tone is pre-pended to the test stimulus which serves as a reference tone for resampling and frequency shift operations. Post-processing resampling and frequency shift precisely synchronizes the stimulus and response waveforms prior to analysis. In this case, the HarmonicTrak algorithm is used for frequency and THD analysis. A2DP frequency response and THD curves are displayed on the first display, followed by A2DP & HFP curves superimposed on a subsequent display. Lastly, the Bluetooth headset’s microphone is tested with HFP and its frequency response is shown on the final display along with the previously collected data.

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