APx Overview


APx Series Audio Analyzers and APx500 Audio Measurement Software
A versatile, powerful audio test experience

The APx Series of audio analyzers represents the state of the art in audio test, with models and options to suit every need from R&D to high-speed production test. Industry-leading analog performance, flexible software with a multi-mode UI, and a wide range of digital I/O and software options make APx the most powerful and versatile series of instruments we’ve ever produced.

Measurement Performance and Speed
With typical residual THD+N specifications ranging from -106 dB (APx515) to -120 dB (APx555), APx Series deliver the analog performance needed by designers and production test engineers around the globe. Add in FFTs of 1.2 million points and full 24-bit resolution, and you have unmatched performance for audio test.

Maximum Versatility in I/O
Each APx Series analyzer (except APx511) has two balanced and two unbalanced analog inputs and outputs plus 216k digital inputs and outputs via AES/EBU, TOSLINK and SPDIF. Additionally, I/O may be expanded for the APx555, APx52x Series and APx58x Series analyzers with optional Digital Serial, HDMI with ARC, PDM and Bluetooth modules. Finally, the Advanced Master Clock (AMC) module handles input and output clock signals to synchronize AMC-equipped analyzers with external equipment (or vice versa), and enable jitter generation and analysis.

Bench Mode & Sequence Mode
Prior to v4.0, the APx operating paradigm involved adding defined measurements to a navigation tree, and the ability to run this series of measurements in an automated procedure called a Sequence. This paradigm continues in APx500 v4.0 and is called Sequence Mode.

Additionally, a new operating paradigm has been developed, called Bench Mode. Rather than pre-defined measurements, this new mode provides a configurable generator and analyzer, a broad family of meters, a comprehensive sweep engine, a time recorder and implementations of the APx Signal Analyzer, Continuous Sweep and Acoustic Response measurements, all to deliver greater flexibility to the user. System 2 and 2700 Series users will feel right at home in Bench Mode.

Side-by-side examples of Bench Mode and Sequence Mode in APx500 audio measurement software

Code-Free Automation & Complete API
APx500 Measurement Software is the most advanced audio measurement interface available. Complex procedures that include user prompts, limits, and calls to external applications can be created directly in the GUI, saving time and money while ensuring painless updates over time, as no development is required.

Create custom interfaces and application-to-application automation using the comprehensive APx API for integration in VB.NET, C#.NET, MATLAB, and LabVIEW development environments. Projects and automation can be shared with other APx units anywhere in the world.

Common Software Platform
From a practical perspective, all APx audio analyzers use the same software, making tests and results easier to share. All settings for a test are saved in a single project file, making it easy to replicate test setups between R&D and production facilities anywhere in the world. Project files are compatible with all APx instruments and each project is self-contained, so there’s never any worry about dependencies or broken links. Users can even embed waveform files and images within a project file.

For customers, contract manufacturers or management, APx automatically generates rich graphic reports, with highlighted pass / fail limits and options to export as PDF, HTML, Excel, CSV, RTF or MATLAB files.

Scalable, Flexible Software
While the APx500 audio measurement software that ships with each instrument is powerful in its own right, Audio Precision offers a wide range of options tailored to specific applications, including:

• Electro-acoustic testing (R&D or Production)
• Perceptual audio test (POLQA and PESQ)
• Speech Transmission Index (STI) measurement