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QA401 Audio Analyzer
QA450 Programmable 8/4 Ohm Load
QA150 High Side Current Sense Amp
QA460 Transducer Driver
QA470 Low Noise Mic Pre-amp
QA351 uV DC Voltmeter (Coming Soon)
QA350 Microvolt DC Volt Meter [RETIRED]
QA101B Mixed Signal Oscilloscope [RETIRED]
Recent Blog Posts
Speaker Impedance Measurements
October 18, 2019
[Draft--revisions coming] In late 2018 a plug-in was added for making speaker impedance measurements. This post takes a look at additional hardware...
Rub and Buzz
October 15, 2019
QA401 release version 1.81 (located HERE) adds speaker Rub and Buzz testing in the form of a plug-in. Rub and Buzz refers to a speaker test that ca...
First Look: Infineon MERUS MA12070
September 28, 2019
The growing portable speaker segment is resulting in some solid Class D innovation from silicon vendors. A new part from Infineon is especially int...
Release 1.791 and Portable Speakers
August 17, 2019
Release 1.791 (located here) has some tools for testing portable speakers & speakers in general. The portable battery-powered speaker segment i...
Automating EQ Tests using Masks
July 19, 2019
Release 1.79 is the latest release of the Q401 application (located here) and release 0.981 is the latest release of Tractor (located here). The QA...
Quickly Characterizing A Tone Knob Using Exponential Sweeps
July 11, 2019
A quick video to show how quickly a tone knob can be characterized using features that have been introduced in the last few releases.
QA401 Release 1.760
June 29, 2019
Release 1.76 for the QA401 should be out early next week and features the ability to build and apply masks to acquired data and deliver a pass/fail...
Basics: Power Amps
June 18, 2019
This post covers some of the more important points to consider when measuring power amps. From the setup to the measurements, if you are looking to...
Characterizing LDO Noise: Part 3
May 21, 2019
In Part 2 of the examination of LDO noise, we ran into the limits of the QA401 while evaluating the output noise of the LT3042. And this shouldn't ...
QA401H, REST and Python
May 17, 2019
Release 0.94 of QA401H is up at Github. Release 0.94 moves a step closer to shipping the headless version of the QA401 control software, and measur...
Characterizing LDO Noise: Part 2
May 10, 2019
Previously we used the QA350 microvolt DVM to look at the standard deviation of different types of LDOs. That measurement helped us understand the ...
Automated Amplifier Testing with Tractor
April 20, 2019
We previously went through a quick characterization of a tube guitar amplifier in the blog post located here, with a promise that we’d come back an...