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Hypnosis
Registered: Mar 2015 Posts: 36 |
SID filter cutoff diagrams
I'm looking for diagrams to detail how the filters in 6581 and 8580 compares to each other. I'd like to see if it is possible to support both chips. |
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chatGPZ
Registered: Dec 2001 Posts: 11523 |
check alankilas page:
https://bel.fi/alankila/c64-sw/curves-8580.png
https://bel.fi/alankila/c64-sw/fc-curves/curves.png |
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Hypnosis
Registered: Mar 2015 Posts: 36 |
Good stuff! Thanks a lot! |
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1BM
Registered: Nov 2002 Posts: 49 |
Alankila homepage dead? Is there a mirror? I would like to look at all this filter distortion effort, this was a great resource. |
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acrouzet
Registered: May 2020 Posts: 100 |
Much of it has been archived by the Wayback Machine: https://web.archive.org/web/20220911222531/https://bel.fi/alank..
6581 filter curves: https://web.archive.org/web/20220916161828/https://bel.fi/alank..
(8580 filter curves were simply a linear function following the equation y=kx+20, where k hovered around 6).
Here's a program that lets you model a custom 6581 curve based on a few parameters: https://web.archive.org/web/20220916161829/https://bel.fi/alank..
Though keep in mind that this emulation is from around 15 years ago. I suggest looking into the source code of libsidplayfp for some more detail on the newest emulation efforts. |