Hi @robertCM
What’s that 100 ohm resistor (R6) doing? I get it’s controlling the current through the stereo jack but why is that needed? Will add your answer to the notes I publish for the components.
hey @mike.egner, I was drawing the schematics for MAKERbuino.
The resistor is simply needed to limit the maximum volume supplied to the headphones. In other words, the headphone output was too loud when I first made the circuit on a proto board and that’s why I added a 100ohm resistor to limit the volume.
Hope this helps 
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Brilliant, thanks @albertgajsak. I did some thorough reading on these kind of circuits and there’s so much variation out there and no clear rules / best practices so I was stumped. Thanks for this.
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No problemo!
Well, there are some rules, but you’d be surprised by how empirical hardware development actually is
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