Professional Audio & Video Solutions


Audio Precision APx555 Audio Precision APx555
You are working with audio on a professional level. And you need to verify the quality of this audio, for instance the audio quality of the chip or audio equipment that you are developing. You need to be precise in your design and therefore you need to measure the audio the best way possible. Preferably with a measurement device that offers you the flexibility to design your own (automated) tests and the versatility to measure a variaty of audio interfaces.

    Introducing the APx555

  • A culmination of 30 years’ audio test experience, the APx555 is an analyzer without compromise. It combines industry-best analog performance with fast, intuitive measurement software and complete support for all APx digital I/O options.

  • Performance, flexibility and versatility

  • The APx555 offers great performance; -120 dB residual THD+N. This is the best performance in the industry. It also offers you great flexibility. you can easily switch between the APx software’s new Bench Mode—enabling real-time interaction with generation and analysis—and the familiar Sequence Mode with pre-defined measurement sequences. And you can do this on a wide variety of audio interfaces. The APx555 supports the complete range of APx digital I/O options: Bluetooth®, Digital Serial, HDMI and PDM.

  • Main Advantages

    Performance of -120 dB residual THD+N
  • Flexibility to implement yuor test sequences
  • Versatility that support many different audio interfaces

Related Solutions

  • SoundWireSM Audio Testing with APx and LnK

    Testing semiconductor audio devices with a SoundWire interface using an Audio Precision APx audio analyzer is conceptually straightforward; the test strategy and implementation is no different than with any other IC device.

    The challenge is the connection to the SoundWire interface, and configuring the SoundWire device. We can with APx and LNK interface!

  • Audio Precision Adds STI (STIPA) Measurement Capability to APx500 Software

    Quantifying the Intelligibility of Speech

    Developed as a method for quantifying the intelligibility of speech with respect to a transmission medium—for example a room, an intercom system, a radio link—STI is an objective measure that provides a single rating between 0 and 1 that predicts the likelihood of syllables, words and sentences being comprehended within the intended medium. The rating is broken down into qualification bands ranging from “bad” (0 to 0.36), to “excellent” (0.75 to 1.0).

  • Lip-Sync The time alignment of the audio relative to the video

    I think you know the problems when audio and video are not in sync, what to do?

    We can give you the figure when you are out of sync to get it back easy.

    In both professional and consumer television and A/V systems, divergent audio and video signal paths and the delay inherent in digital processing provide many opportunities for the program sound and picture to fall out of synchronization

Related Blog messages

  • What is new in APx software 4-4

    The latest release of APx500 audio measurement software, version 4.4, is available for download at

    The release includes minor feature improvements, including regulation enhancements and the option to maintain Bluetooth® connection even when Bluetooth is not selected as output or input.

    APx500 Measurement Software
    (Must be a registered user of
    and logged in to download)

  • Perceptual audio analyse met APx 525


    APx500 v3.0 now supports a PESQ (Perceptual Evaluation of Speech Quality) option for use with APx audio analyzers. Obtain MOS results directly in APx projects,

  • PDM option for APx

    Pulse Density Modulation (PDM) is a one-bit, high rate data stream that conveys a signal by modulating the density of the pulses. A typical application for PDM is the Micro-Electrical-Mechanical System (MEMS) microphone found on smartphones.

    The APx PDM option provides direct connectivity for audio devices that have a PDM output (such as a MEMS microphone) or input (such as the decimator on a smartphone chip). In addition to all the standard audio measurements, APx provides variable DC voltage, variable sample rate, and a PSR (power supply rejection) measurement to test the device’s full operating parameters. No other analyzer combines direct PDM connectivity with APx’s best in class speed, ease-of-use, and performance.