Gianluca Sperti
Square wave testing
Updated: Jan 16, 2019

Summary
Square wave testing
The 1kHz square wave is a test to investigate quickly the performance in the frequency domain of audio electronics, it is so convenient that makes it very widely used and well know by everyone in this passion. A signal that changes abruptly from low to high is injected at the input of an amplifier or preamplifier under test and the output compared to the input; undershoots, resonances and other anomalies can be easily detected and traced back to the frequency behaviour of the piece of equipment. The maths behind the relationship between the square wave (a time dependent phenomenon) and the frequency response are not so straightforward, for the sake of this short discussion let’s only remember that a 1kHz (or any other frequency) square wave is actually a sum of infinite harmonics so any imperfection in the frequency domain of the device under test will be reflected in the square wave test. The square wave test very quick and revealing of imperfections of the audio device and can be performed with cheap and basic instruments (an oscilloscope and a signal generator). Somehow it can also give quantitative indications of the quality of the audio device under test.
Download the complete PDF file (with all the pictures, graphics, tables) under the section "SUPPORT/DOWNLOAD".
https://docs.wixstatic.com/ugd/91e8f2_fcd287c9eed24bb0a6a490f7ef8faf1c.pdf
If you have any questions, please don't hesitate to send us an email to the following email address: info@audiodinamica.com
Author: Gianluca Sperti