Correlated Cross-Domain Measurement & Reduced Test Time

Version 6.0 of APx500 audio measurement software offers multiple simultaneous input types

BEAVERTON, OREGON, June 10, 2020: Audio Precision today released the latest update to APx500 audio measurement software, version 6.0. With this release, APx software supports multiple simultaneous input types, enabling the concurrent measurement of up to 16 channels of digital and 8 channels of analog audio data. This new multi-input capability, paired with the highest channel count and widest range of digital I/O available, provides APx users critical cross-domain insight and the opportunity to reduce testing time.

An illustration of the new multi-input feature introduced with APx500 software version 6.0, in this case an example application of 16 digital mics as the DUTs on Input 2 and an analog measurement mic as the reference on Input 1.

Multi-Input Defined

Multiple simultaneous input types, or multi-input, is the ability to activate a second input type on any APx modular audio analyzer, or APx515 analyzer, and make measurements simultaneously on analog and digital signals. With two input types enabled—for example, analog for one or more reference microphones and PDM 16 for an array of MEMS microphones—there will be measurement results for every enabled input channel. In addition, the sensitivity or gain function of digital microphones and other converters can be directly found via a new derived result, Sensitivity, which displays the RMS Level relationship between the analog and digital inputs.

The multi-input feature is available for use in both Sequence Mode and Bench Mode and supports all the essential measurements used for the analysis of microphones and microphone arrays. This includes Transfer Function, a dual-channel FFT analysis function added in the previous release of software. With multi-input and Transfer Function, the complex, magnitude and phase, relationship between multiple analog or digital microphones or other cross-domain devices can be found.


For audio devices that can have both analog and digital outputs active simultaneously, the new multi-input feature enables the simultaneous evaluation of those outputs, whether in a design lab or on a manufacturing line. Concurrent measurement of both signal types also has the potential to reduce test times which is especially important in manufacturing applications.

Multi-input is especially useful for devices with digital microphones—smart speakers, mobile phones, Bluetooth® headsets, and other devices—as it allows for the simultaneous measurement of the device’s microphone in conjunction with an analog measurement microphone as a reference.

“Our latest major release of APx software delivers a powerful new capability with broad application in both the design and manufacture of audio products,” stated Mike Flaherty, Audio Precision Chief Executive Officer. “Whether providing added insight to the design engineer or accelerated test time for the manufacturing engineer, multi-input demonstrates the power and value of APx audio measurement software.”

With this latest release, new APx audio analyzers will ship with version 6.0 software and one year of software maintenance, effectively licensing that instrument for APx version 7.0 when it is released (in addition to any minor releases that occur between v6.0 and v7.0). New APx analyzers purchased with version 5.0 (between December 18, 2018 and June 10, 2020) are licensed for version 6.0 in accordance with one year of software maintenance and users need only download v6.0 from

Software upgrades are available for owners of Legacy APx analyzers, with options for upgrading from v4.x (or earlier) to v5.0, from v4.x to 6.0, and v5.0 to v6.0. Software maintenance contracts are likewise available, providing for purchase, entitling the user to an additional major software release.

Release 6.0 is compatible with all analyzers in the APx500 Series. An APx KeyBox is required to run v6.0 on Legacy APx analyzers. APx KeyBoxes already installed on Legacy analyzers (for v4.6 and 5.0), are also compatible with v6.0 and only require an updated license file once an upgrade is purchased.

Watch a Multi-Input Demonstration

Read the APx500 What's New - v6.0

About Audio Precision

Audio Precision (AP) is a recognized world leader in electronic audio and electro-acoustic test instrumentation. Since 1984, AP’s analyzers have helped engineers to design and manufacture innovative solutions ranging from semiconductor devices to consumer, automotive, and professional audio products. For more information, visit