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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
QA350 Microvolt DC Volt Meter [RETIRED]
QA101B Mixed Signal Oscilloscope [RETIRED]
Recent Blog Posts
NAMM 2020 and Speaker Compression
January 28, 2020
[Draft...revisions coming] NAMM 2020 has come and gone, and as usual the event was informative and educational. I had a discussion with a person wh...
Automating Pedal Measurements with Tractor
January 15, 2020
We have a new forum located here. It's based on Discourse, which is a bit different form most forum software. Discourse is optimized for short, qui...
December 04, 2019
Let's say the first 50 units of your new widget prototype have come off the line. You're excited because this is the first time you've built more t...
Speaker Impedance Measurements
October 18, 2019
In late 2018 a plug-in was added for making speaker impedance measurements. This post takes a look at additional hardware requirements to be aware ...
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
This is Part 3 of 3 parts.Part 1 of this article is located here.Part 2 of this article is located here. In Part 2 of the examination of LDO noise...