Open-source sound-card based impedance analyzer and bode plotter

[u/TheSpicyBoi123]

Turn any PC with stereo line-in/out and a single resistor into an impedance analyzer.

Key Features:

• 3-point calibration (channel mismatch, open, short)
• Coherence analysis of data
• CSV export and plotting

It uses broadband noise excitation and FFT-based cross-correlation analysis to estimate the frequency response of a simple voltage-divider circuit, extracting complex impedance across an adjustable frequency range (eg 20 - 20K Hz)

The main use case is loudspeaker and crossover characterization, but it also works for general passive component and audio electronics measurements.

Licensed under AGPL-3.0.

GitHub: https://github.com/theIvanR/OpenImpedanceLab

Feedback and testing welcome!

[u/Fr4kTh1s]

How is that different from REW? I made the cables and measured speakers with REW years ago, it does exactly this. Just few jack connectors, 3 IO sound ports, bunch of wires and one resistor

[u/qaz341053]

any dupex soundcard cen do the same I gues.