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A comment on Plug a guitar in your C64 and use it as a wah pedal.

Re:Plug a guitar in your C64 and use it as a wah pedal by classichasclass on Saturday September 24, 2022 @02:34PM (#32965413)
Warning to the curious: it is very easy to fry your SID connecting directly to the audio in (don't ask how I know this). Make sure of your levels before you connect, and don't plug this in with the power on in case there's a short.
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Re:Plug a guitar in your C64 and use it as a wah pedal by spacecadet_ on Sunday September 25, 2022 @08:14AM (#32970615)
Is this still the case with recent audio hardware? I was under the impression that a typical instrument's output levels are far too low to cause any damage and that all inputs would be surge protected.
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Re:Plug a guitar in your C64 and use it as a wah pedal by the_other on Saturday September 24, 2022 @02:58PM (#32965569)
> don't ask how I know this

Tease!

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Re:Plug a guitar in your C64 and use it as a wah pedal by myself248 on Sunday September 25, 2022 @12:20AM (#32968929)
I also know this.

In my defense, I was like 9 at the time and didn't know about AC-coupling for audio signals yet. That smoked SID is still down in my basement somewhere, I wonder how much of it still works.

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Re:Plug a guitar in your C64 and use it as a wah pedal by diydsp on Saturday September 24, 2022 @03:29PM (#32965817)
any suggestions to protect it? e.g. buffer with an op-amp, right? Any way to use diodes for static protection, etc.?
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Re:Plug a guitar in your C64 and use it as a wah pedal by satiric on Saturday September 24, 2022 @05:49PM (#32966831)
One common way to provide input overvoltage protection is through a pair of schottky diodes. This article is a good resource https://www.digikey.com/en/articles/protecting-inputs-in-dig...
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Re:Plug a guitar in your C64 and use it as a wah pedal by buescher on Saturday September 24, 2022 @06:58PM (#32967348)
That's a pretty good article. Also, the classic one-volt-or-so voltage limiter is a pair of antiparallel silicon diodes. You can put them in series for a bigger limit.
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Re:Plug a guitar in your C64 and use it as a wah pedal by classichasclass on Saturday September 24, 2022 @05:58PM (#32966898)
There are some good practical solutions here ( https://www.lemon64.com/forum/viewtopic.php?t=55483&sid=2710... ) but the most important thing is keep the voltages down. They suggest three volts max peak to peak, which seems prudent.
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