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Audio Precision Technical Content

Utilities, Projects, Plug-ins & Macros (68)

Utilities, Projects, Plug-ins & Macros

2700 Series S-AES17 and OPT-2020 Filter Set Bit Macro

This AP Basic macro reads or sets the 2700 series instrument EEPROM firmware configuration to indicate the currently installed pre-analyzer filter (S-AES17 or OPT-2020). If you install or remove pre-analyzer filter hardware, you must set the EEPROM configuration for correct software operation. Requires AP2700 or APWIN version 2.24 or later control software.


AP Basic Database Connectivity Sample Files v1.0


AP Basic Scripting Sample Files v1

These files accompany the "AP Basic Scripting" training video found at http://ap.com/support/training


AP2700 & ATS-2 Resources Disc v102

The Audio Precision Resources Disc contains Sample Tests, the Performance Check and documentation to help you operate your AP2700 or ATS control software compatible audio analyzer. AP2700 or ATS control software is required. The installer includes both AP2700 and ATS-2 resources. You will be prompted to choose which components you wish to install.


AP2700 ADSR Measurement Test

This measurement looks at the four segments of an envelope expressed as amplitude vs. time; Attack, time for a signal to reach full amplitude, Decay, time for the signal to drop from the initial attack level to the sustain level, Sustain, time the signal remains at the constant amplitude, and Release, time for the signal to return to an off or zero amplitude condition.


AP2700 Complex Impedance Macros v1

Includes instructions and discussion.


AP2700 Crest Factor Test v1

File configured to measure crest factor. See knowledge base article for complete explanation.


AP2700 DIM Measurement Macro v1

Accompanies KB article "DIM 30 and DIM 100 Measurements per IEC 60268-3 with AP2700"


AP2700 Damping Factor and Output Impedance Measurement Macro v2.0

Measures and graphs the damping factor and output impedance vs. frequency of a power amplifier.


AP2700 External Crosstalk vs Frequency Test

Accompanies KB article "Open Loop Crosstalk vs. Frequency."


AP2700 FFT Scaling for Noise Macro v1

AP2700 macro and test file to accompany the KB article "FFT Scaling for Noise."

Contains several functions that are useful for performing calculations on FFT spectra, including FFT spectrum integration with window correction. There is also a subroutine that will convert a measured FFT spectrum to amplitude spectral density in dB relative to 1.0 V/√Hz, or FS/√Hz, and plot it on the graph.


AP2700 Frequency Error Correction Test

This AP2700 test file accompanies the KB article "Syncing the 2700 Series Generator to an External Reference."


AP2700 Glitch Detection Test

AP2700 test file to accompany the knowledge base article on Glitch Detection.


AP2700 GraphBuilder Macro v2.0 (View previous versions)

GraphBuilder is a macro that extends the two-dimensional graph capability built into AP2700 and ATS control software to include three dimensional and polar graphs. For use with APWIN, download the previous version (1.1).


AP2700 I2S Jitter Measurement Test v1

This file accompanies the knowledge base article "I2S jitter measurement with the SYS-2722." It demonstrates how to measure digital interface jitter using the digital unbalanced input of the instrument.


AP2700 PSRR Test

Tests PSRR (power supply rejection ratio). See the associated KB article for instructions. Contains .at27 test and .ads sweep file.


AP2700 Prompt Using Windows API Macro

This AP Basic macro demonstrates the use of a modified AP.Prompt for use in control loops. It allows the AP.Prompt text to be changed while a prompt is displayed without flashing or refreshing the entire prompt window.


AP2700 Sample Rate Error Measurement Macros v2

Many devices contain internal clocks that are not accessible but that need to be measured. Examples include the A/D converters in USB headsets, and the D/A converters in MP3 players and smart phones. The internal sample rate error of these types of devices can be indirectly determined by measuring the frequency error of a known tone. This download contains two AP2700 macros that calculate the error. See the associated KB article for instructions.


AP2700 Send Bar Graph Data to Serial Port Macro

Macro and test file demonstrate how to send a bar graph reading to an RS-232 serial port.


AP2700 and ATS Get all FFT Bins Macro v1

Illustrates setting up the sweep panel to return all FFT bins. For 2700 Series and ATS-2. The macro includes a function that gets the Sample Rate and FFT length, and in addition to setting up the sweep panel, it retrieves the FFT level spectrum in units of Volts.


AP2700 and ATS Graph Trace Setting Macro v1

Lets you set the graph trace properties quickly (line color, thickness, pattern, comments), even if you aren’t otherwise using macros or automation, by adding this macro to your Quick Launch toolbar.

Zip file includes macros for AP2700 and ATS, and Quick Launch installation instructions.


AP2700 and ATS Split Stereo Waveform Macros v0

The ATS-2 and 2700 Series GPIB implementation requires that waveforms loaded into the analog and digital Arbitrary waveform buffers be mono files. Many of the sample waveforms provided for the two instruments are Stereo. This download contains two macros, one for each instrument, that can be used to split the stereo waveform into mono files.


APWIN Basic to ATS Basic Translator v1


APx Active Loadbox Utility v4.2 (View previous versions)

Integrates APx with AudioGraph’s Active Loadbox for automated and comprehensive power amplifier load measurements. Requires the Active Loadbox hardware for use.

An overview of the measurement principles and detailed usage instructions is contained in the KB article: Measuring Power Amplifiers with Reactive Loads.


APx Barcode Scanner Interface v3.2 (View previous versions)

A barcode scanner may be useful in production testing, not only to expedite data entry, but to eliminate the possibility of initiating the wrong test routine. The APx Barcode Scanner Interface is a small VB.net application (Run_Barcode_Project_ID.exe) that automatically loads an APx project who's name matches the barcode data.


APx Blu-ray Disc Sample Project v1

APx Blu-ray Disc Sample Project with instructions. Requires APx585 with HDMI.


APx Bode Plot Project v1

An APx project that creates reports in Bode Plot format. Requires APx500 v3.2 or later.


APx Burst Waveform Utility v4.2 (View previous versions)

This utility creates sine burst waveforms and then saves them and/or uploads them into the APx generator. Burst waveforms can be useful in testing a number of properties, including power supply transient response and reserve, meter ballistics, and compressor/limiter behavior.


APx Click and Pop Measurement Projects

For use with the APx Sound Level Meter Utility. See the associated KB article on Click and Pop Measurement for full discussion and instructions.


APx Damping Factor Measurement Utility v4.2 (View previous versions)

The APx Damping Factor Measurement Utility plots audio amplifier damping factor vs. frequency.

The version number of this utility must match the version of the APx500 software that you are running.


APx EQ .wav Files Utility v1.04

The APx EQ .wav Files Utility lets you apply equalization to generator source .wav files. When given an original .wav file and an EQ curve file, it creates a new EQed .wav file. Includes both graphic interface and command line versions. The utility is useful to EQ PESQ generator files for a given stimulus speaker. Download includes instructions. Note that any version of APx500 may be used with this utility, and version numbers do not correspond to APx500 versions.


APx Equalized THD Measurement Utility v1.0

This utility allows you to calculate post equalization THD on-the-fly. The utility operates from the command line (no user interface) and is called during an APx project by adding a Program step to the sequencer. Includes complete instructions and project file.


APx FFT to Octave Conversion Utility v4.2.1 (View previous versions)

Converts FFT spectra to fractional octave spectra. Includes instructions which discuss the theory behind the conversion.


APx FM MPX-RDS Demo Project v1

A simple APx project file to demonstrate testing of FM transmitters and receivers, including automotive head units. Includes a set of MPX-RDS-encoded sweeps and tones.


APx FM MPX-RDS Waveform Creation Utility v4.2 (View previous versions)

This utility can create a file containing a multiplexed and RDS encoded waveform of stereo sine waves, and upload it to the APx500 measurement software. Accompanies Technote TN-105, "FM Radio Receiver Testing with APx Audio Analyzers."


APx Generator EQ Files v1

These files can be used with APx500 v2.7 or later to create equalized sweeps or equalized multitones.

Included are RIAA, FM 50uS, and FM 75uS emphasis and de-emphasis curves.


APx J-Test (Jitter) Measurement Utility v4.2 (View previous versions)

Measures jitter at the receiving end of an AES3/SPDIF connection by using a special J-test stimulus signal and analyzing the analog output spectrum. Displays graphs showing the FFT spectrum, the jitter spectral density, and the integrated jitter, in addition to a total jitter value. Tools are included for manipulating the graphs, exporting data, and printing.

Download includes the utility, J-test stimulus waveforms, and Technote 118 with instructions. The utility version must match the version of APx500 that you are running.


APx Mixing Console Sample Project v1

APx mixing console sample project with instructions. Requires any APx instrument.


APx Multichannel Amplifier Power Output Sample Project

APx sample project for measuring the power output of a multichannel amplifier according to EIA/CEA-490-A, section 6.1, where non-measured channels are attenuated by 9 dB. A related KB article includes an explanation of the measurement.


APx Output Impedance Measurement Utility v4.2.1 (View previous versions)

The output impedance of a device can easily be calculated by measuring its output voltage with and without a known load attached. The APx Output Impedance Measurement Utility simplifies the procedure by calculating and graphing the results. See the accompanying knowledge base article for an explanation and instructions.

The version number of this utility must match the version of the APx software that you are running.


APx PSRR Measurement Utility v4.2 (View previous versions)

Power Supply Rejection Ratio (PSRR) is a measure of a device’s ability to reject noise from the supply used to power it.

Download includes the utility and TechNote 106: Measuring Power Supply Rejection Ration (PSRR). The utility version must match the version of APx500 that you are running.


APx Phantom Power Measurement Project

Allows measurement of phantom power on a microphone preamplifier, with and without a simultaneous audio signal. Requires a special Phantom Power Test Fixture, described in Technote 114: Measuring Phantom Power (included).


APx Polar Plot Utility v4.2.4 (View previous versions)

The APx Polar Plot Utility is a Windows application for making polar measurements of loudspeakers or microphones with an APx500 audio analyzer and for creating 2-dimensional polar dispersion plots from the measured data. The APx Polar Plot utility also requires the SPK or SPK-RD software option to be installed on the connected APx audio analyzer. If you require a SPK-RD software option, please contact your Audio Precision sales representative.


APx Portable Audio Player / Headphone Test Utility v4.2 (View previous versions)

Tests portable audio players and headphones packaged as a set, and as individual components, for compliance with the BS EN 50332 standard. Works with any APx Series analyzer. The version of APx500 software must match the utility version. Includes Technote 107 with full instructions.


APx Power Amplifier (Linear) Sample Project v1

APx power amplifier (linear) sample project and instructions. Requires any APx instrument.


APx Process CSV Data Utility v2.0

This utility allows you to post process .csv files saved by the APx Measurement Recorder measurement and return the results to a CSV file and optionally to an APx Defined Result. It operates from the command line (no user interface) and is called during an APx project by adding a Program step to the sequencer. A sample project file is included to demonstrate its usage and how to import results data into an APx Defined Result.

Five different computations may be performed:
1. Return Frequency of Derived Result Max function (GetMaxDRFreq)
2. Return X/Y Trace comparison (Compare)
3. Data restructuring (AppendsToResult)
4. File deletion (DeleteFile)
5. Trace positioning based on defined trigger (Trigger)


APx Production Test Demonstration Project v1.0

This zip file contains an APx project file named "PT-Demo External Loopback.approjx" that illustrates many of the production test and automation features added in release v4.2 of the APx500 measurement software. The project file focuses on an electro-acoustic application, specifically loudspeaker test. The file also contains a 15-page presentation describing how to use the demonstration project.


APx Repeat Measurement Utility v3.3 (View previous versions)

The APx Repeat Selected Measurement Utility allows you to continuously repeat any selected APx500 measurement. This is useful when adjusting a device, circuit, or component on the bench and you want to monitor changes as you make them in real time.

Download includes installer and instructions. The utility version must match the version of APx500 that you are running.

3.3 is the last version of this utility. Repeat capability is already included in Bench mode in APx500 v4.0 and later.


APx Reports Tutorial A Files v1

The files created while doing "Tutorial A: Making a Custom layout from the Default layout" in the APx500 program Help. Use these files if you wish to skip Tutorial A and proceed with Tutorials B and C.


APx Run External Program Project v1

This APx project and related files demonstrates how to run an external program from APx500. Includes THD+N measurement and Stepped Frequency Sweep measurements. The project file calls the Goldwave audio editor program, so you will either need to install Goldwave, or substitute another audio player with a command line interface. Accompanies the kb article "Running an external program from APx500," which gives a complete explanation.


APx STI Plug-in v1.0

For designers of public address, flight recorder and police/fire/emergency communications systems, the APx Speech Transmission Index (STI) plug-in is a software add-on for the APx500 that provides a STIPA measurement and Speech Level measurement conforming to international standard IEC 60268-16 (2011).

NOTE: The STI plug-in is a software option and requires the purchase of an iButton (APX-SW-STI) for measurement functionality. Download and installation of the plug-in, without an iButton, enables the measurement in demo mode only. The APx STI plug-in requires v4.2.1 or later of APx500 audio test software.


APx Self Test v4.2 (View previous versions)

Automated self test for all APx instruments. Run this test to confirm proper operation and before sending an instrument in for service.


APx Sound Level Meter Utility v4.2 (View previous versions)

Allows an APx500 Series Analyzer to measure acoustic noise or sound in the environment, taking the place of a handheld sound level meter. Using the analyzer adds the capability to perform spectrum analysis, and to visualize the character of the sound signal over time. The latter is especially valuable when measuring non-steady-state sounds, such as a pulsating alarm. Technote 113, included, describes the theory and how to use the utility.


APx Speaker Impedance Measurement Project

This project measures loudspeaker impedance using the constant voltage method.

Complete instructions and explanation are in the KB article "Measuring Loudspeaker Impedance Using APx Derived Measurement Results".

An external sense resistor is required for this project. The "APx Speaker Impedance Measurement Utility," also available for download, can utilize the built-in source resistor in APx analyzers.


APx Speaker Impedance Measurement Utility v3.3.1 (View previous versions)

This utility for APx analyzers allows you to make an impedance vs frequency sweep across a loudspeaker, and then see the graph and data results directly in ohms. Clicking Help in the utility will display the complete instructions, including a discussion of the theory behind it. It can utilize the built-in source resistor on APx analyzers to make impedance measurements.

NOTE: This utility is only compatible with APx500 Software v3.3 or earlier. For users with APx500 v3.4 or later, options APX-SW-SPK-RD and APX-SW-SPK-PT provide a range of acoustic measurements, with SPK-RD including Thiele-Small characterization. An impedance-only alternative is also available for download and is compatible with APx500 v3.4 and later – please see the APx Speaker Impedance Measurement Project. This project requires an external sense resistor and uses the constant voltage method.


APx Splice Utility v2.0

Splice is a CLI utility that combines separate LF and HF measurements into a single full frequency response result.


APx THD Sweep Individual Harmonics Project v3.0

Produces a separate trace for each harmonic H2 through H10 (can be extended to H20), as both a level and as a ratio, and displays them all on one graph. Each harmonic can easily be enabled or hidden. Makes use of the Export Data and Import Data steps in the automated project sequencer. I/O connectors and measurement bandwidth should be set in Signal Path Setup before running. This project will open in APx500 v3.0 or later.


APx TTA Speaker Test Utility v4.2 (View previous versions)

This APx utility facilitates testing of small loudspeakers according to requirements of the South Korea Telecommunications Technology Association (TTA) Standard number TCB-0054(00), “TTA Verified Testing Criteria for Micro/Slim Speakers” using an Audio Precision APx500 Series audio analyzer.

Note that the version of this utility must match the version of APx500 that you are using it with.


APx Waterfall-CSD Plot Utility v4.2 (View previous versions)

The APx500 CSD Utility is a Windows application for making a Cumulative Spectral Decay (CSD) plot, sometimes referred to as a waterfall plot, from the measured impulse response of a loudspeaker. The APx CSD utility also requires the SPK-RD software option to be installed on the connected APx audio analyzer. If you require a SPK-RD software option, please contact your Audio Precision sales representative.


APx Waveform Computes Utility v2.0

The APx Waveform Computes Utility extends the capabilities of APx500 by making Fast RMS (root mean square) measurements. Additionally, it utilizes Fast RMS for a number of useful tasks: audio/video synchronization, dropout detection, and pop/click detection. Download includes utility, instructions, and example project file.


APx Waveform Generator Utility v4.2

The Waveform Generator Utility (APxWfmGenerator.exe) allows you to generate .wav files for a wide range of test signals, with selectable sample rates, bit depths and channel counts.

You are free to copy this utility to other computers or media, where you can generate the audio files you may need for external source testing.

Note that the version number of this utility does not correspond to APx500 software versions and APx500 is not required.


APx Wow and Flutter Measurement Utility v4.2 (View previous versions)

Enables an APx500 audio analyzer to measure wow and flutter, according to standard “AES 6-2008—Method for Measurement of Weighted Peak Flutter of Sound Recording and Reproducing Equipment” (IEC 60386 Weighted). Includes an FFT of the demodulated waveform, as well as an unweighting option.


ATS-1 HPIB Emulator Sample Programs v1.0

HPIB is an interface protocol used with older Hewlett-Packard instruments. These programs demonstrate the ATS-1 capability to operate in HPIB emulation mode.


ATS-2 Loudspeaker Impedance tests v1

ATS-2 Loudspeaker Impedance files associated with KB article 105


ATS-2 Performance Check v1.63

ATS-2 Performance Check macro and test files for all ATS-2 instruments. Running the Performance Check verifies proper instrument operation, and provides diagnostic data for Technical Support evaluation before sending an instrument in for service. Perf Check v1.63 is for use with the ATS v1.60 control software.


ATS-2 Samples Only

Sample Test files for ATS-2


Matlab Toolbox v5.1

Set of MATLAB functions for audio applications such as reading and writing waveforms and filters for 2700, ATS-2, and APx


System Two Family Performance Check v1.24

System Two Family Performance Check (Perf Check) for all System Two and 2700 Series instruments. Running the Performance Check verifies proper instrument operation, and provides diagnostic data for Technical Support evaluation before sending an instrument in for service.


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