Just bought a C64 :-)

[arkpandora]

http://www.prophet64.com/

[arkpandora]

Actually this fourth voice is the main problem of the 8580.  It is strange to notice that the number of musics that used this voice increased in the second half of the C64's life, despite this problem that prevents any digitized sound to be audible among synthesized sounds.  As if no musician had noticed the problem, or been told about it in case they were using an older C64.

What does this resistor-fix consist of ?

[arkpandora]

Here is a good technical site about the SID, especially the differences between the successive revisions :

http://sid.kubarth.com/