Bluetooth® Duo Module for APx B Series Audio Analyzers
Next-generation, integrated Bluetooth Audio Test Solution

The Audio Precision Bluetooth Duo option is a completely revised, upgraded Bluetooth® hardware module, with dedicated source and sink radios, new Bluetooth chips and the latest firmware, higher RF power, and improved RF shielding. Supported by Audio Precision’s APx500 measurement software (NOTE: version 4.5 or later required), Bluetooth Duo offers a range of new audio codecs, new operational features in the supported profiles, and faster connection times. The option can be installed into any APx modular analyzer manufactured later than mid-2012. (AP’s legacy Bluetooth module is available for earlier generation APx analyzers or cases where APx500 software v4.4.2 or earlier is required.)

As an APx module, Bluetooth Duo is part of an all-in-one solution, integrated into the analyzer and leveraging the power and flexibility of the APx system. Bluetooth Duo can share the analog, digital, chip-level I2S and TDM protocols, PDM, or HDMI input/output capabilities installed in the analyzer. Intuitive and powerful, the APx500 software provides access to a long list of audio measurements and Bluetooth settings and parameters. APx creates logs of sent and received commands and interactions, and can easily automate Bluetooth I/O, connection, pairing, and settings commands in a stepped sequence for production work. When new Bluetooth features and improvements are made available, Bluetooth firmware upgrades can be distributed and installed in the field.

APx Bluetooth Settings, v4.5 software

Typical APx500 Software Bluetooth Settings Dialog

Bluetooth Specifications and Profiles
APx Bluetooth Duo incorporates the audio features mandated within the Bluetooth 4.2 core specification and supports the Handsfree Profile (HFP v1.7), Headset Profile (HSP v1.2), Audio-Video Remote Control Profile (AVRCP v1.4) and Advanced Audio Distribution Profile (A2DP v1.3). With dedicated source and sink radios, AP’s Duo module easily switches between the roles of A2DP source and sink (including AAC), HFP/HSP audio gateway and handsfree, and AVRCP target and controller

A2DP Codecs
The introduction of AP’s Duo module expands the list of A2DP codecs available to Bluetooth-equipped APx Series audio analyzers to AAC, aptX, aptX-HD, aptX-LL and SBC. APx Bluetooth Duo can act as either source or sink for each of the supported A2DP codecs. Note regarding pure sine signals and AAC codec.

Comprehensive audio test from the recognized standard
Once connected, every audio characteristic can be measured. Key features include 30+ one-click audio measurements (including all standard weighting filters), 1.2M point FFTs, real-time oscilloscope monitoring, custom reports, statistical calculations, and quasi-anechoic acoustic measurements. With 21 measurements in one second, the APx multitone analyzer is ideal for Bluetooth production test.

Perceptual audio tests
APx500 supports two popular perceptual audio tests used for speech quality evaluation: POLQA (Perceptual Objective Listening Quality Assessment) and PESQ (Perceptual Evaluation of Speech Quality). Both deliver Mean Opinion Score (MOS) results directly in APx projects.The APx Bluetooth Duo module acts as an ideal transmitter or receiver, allowing the device under test to be accurately assessed. More information on Perceptual Audio Testing

APx Bluetooth Duo Data Sheet

Bluetooth Core Version

Profile Versions
A2DP v1.3
AVRCP v1.4
HFP v1.7
HSP v1.2

A2DP Audio Codecs

HFP Audio Codecs

RF Connection
SMA (two)

RF Input Impedance
50 Ω typical

RF Output Impedance
50 Ω typical

RF Power
Typical maximum +8 dBm

RF Sensitivity
≤ –81 dBm Typical

Full Specifications: For full specifications on the APx Bluetooth Duo I/O module, please see the Installation and Specifications Guides for any of the modular APx audio analyzers:

APx555 Installation Instructions & Full Specifications
APx52x Series and APx58x Series Installation Instructions and Full Specifications