uneksija

Hi! This is slightly off topic since it's about the SID chip but not about the MIDIboxSID. Maybe I'll build a MIDIboxSID in the future (it's really cool!), but my question is about circuits for protecting the SID. I'm asking from this forum since I'm sure there's a lot of SID expertise here. So what I'd like to do is to connect my Commodore 64 to a mixer or to an amplifier. However, I've heard that voltage spikes, when connecting cables, or when turning off the mixer while the C64 is connected, can fry the SID. The C64 does have a little transistor circuit for protection etc. at the output, but it seems it's not enough. So... How are your experiences in this matter with the MIDIboxSID? Has anyone fried any SIDs in the way I described? How is the SID protected in MIDIboxSID? I'd love to hear recommandations for protection circuits so that I don't kill my C64's SID. So far I've gotten the following suggestions: -using an isolation transformer -using diodes from signal to ground and from ground to signal so that they'll make possible voltage spikes go to ground instead of the SID -using an opamp as unity-gain follower (I guess the protection transistor in the C64 is doing something similar) Please help me if you know something about this :) Thanks for any help in advance!