*[https://youtu.be/yadWu7hs4MU Oscilloscope comparison of 4 different SID chips]
* [https://github.com/libsidplayfp/SID_schematics/wiki SID internals documentation]
*[https://www.oxyron.de/html/registers_sid.html Oxyron SID reference]
*[[Media:SID 6581 datasheet.pdf|SID datasheet]]