Scimpy: open-source speaker design, impedance measurements, & book (Win/Mac/Linux)
Scimpy Speaker Design Tool:
Sound Card Based Impedance Measurements in Python
I've been working on an open-source speaker impedance testing tool using your soundcard as an ADC/DAC; extracts electrical, mechanical and acoustic component values; design and model speaker performance from T/S values; closed and vented-box optimization; and cross-over/impedance matching design. At the same time, the manual for the software has turned in to quite a stand-alone book in which some might be interested; the book is open-source as well.
Screen shot:
Book (work in progress! comments welcom):
https://github.com/maqifrnswa/scimpy/blob/master/doc/scimpy.pdf
Code Repository:
https://github.com/maqifrnswa/scimpy
Feedback:
https://github.com/maqifrnswa/scimpy/issues
What Works:
Tech details:
Plan:
License: code is GPL3, book is CC-BY-SA 4.0.
Feedback welcome, fork it and pull request if you're interested as well! Book contributions/edits/corrections/discussion is welcome as well.
EDIT:
I went over to windows and test it out, it works the same as Linux. Box modeling works perfectly; in the impedance tester, some warnings might pop-up if you try to verify sound card compatibility, but if you ignore those warnings it actually works as intended. Below is a screen shot of the same speaker as the above screen shot, just modeled in an infinite baffle while the top screen shot was modeled in an ideal B2 closed box.
Scimpy Speaker Design Tool:
Sound Card Based Impedance Measurements in Python
I've been working on an open-source speaker impedance testing tool using your soundcard as an ADC/DAC; extracts electrical, mechanical and acoustic component values; design and model speaker performance from T/S values; closed and vented-box optimization; and cross-over/impedance matching design. At the same time, the manual for the software has turned in to quite a stand-alone book in which some might be interested; the book is open-source as well.
Screen shot:

Book (work in progress! comments welcom):
https://github.com/maqifrnswa/scimpy/blob/master/doc/scimpy.pdf
Code Repository:
https://github.com/maqifrnswa/scimpy
Feedback:
https://github.com/maqifrnswa/scimpy/issues
What Works:
- Finds system T/S from component values, and visa versa
- Modeling infinite baffle performance from T/S
- Modeling closed-box performance from T/S
- Calculate & model optimum B2 closed box from T/S
- Cross-platform soundcard control for impedance measurements, swept frequency output input and frequency analysis (no impedance measuring set up yet)
- Book has detailed description and derivation of all T/S parameters, pretty much covering all topics except large-signal analysis and far field diffraction from a baffle.
Tech details:
- Python, PortAudio, and Qt for cross-platform support with easy learning curve for contributors.
- Book is latex. I'm thinking of uploading it to a print-on-demand site and "selling" it at-cost if people want a physical version of the book. I might, actually!
Plan:
- Finish vented box modeling and optimization (QB3-B4-C4 alignment)
- Cross-over design
- Take data from impedance measurement and extract T/S parameters.
- Windows & Mac binaries. It runs on all platforms, but you need to install Python and supporting libraries at the moment. Once it's further along we can offer a single file that just runs. I'm on Linux, so I just haven't had the time to build binaries on Windows (and I don't have a Mac, so I'd need someone with one to volunteer to build it!)
- Clean up code, some of it is not great software engineering, but i'm just trying to get it all working at the moment.
License: code is GPL3, book is CC-BY-SA 4.0.
Feedback welcome, fork it and pull request if you're interested as well! Book contributions/edits/corrections/discussion is welcome as well.
EDIT:
I went over to windows and test it out, it works the same as Linux. Box modeling works perfectly; in the impedance tester, some warnings might pop-up if you try to verify sound card compatibility, but if you ignore those warnings it actually works as intended. Below is a screen shot of the same speaker as the above screen shot, just modeled in an infinite baffle while the top screen shot was modeled in an ideal B2 closed box.

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