Funny, EEVBlog wondering about the center negative DC jacks :-)

[drolo]

[alanp]

Saw that, you can tell that Dave has spent no time whatsoever around any pedal nerds. He goes on about how practically no one uses centre-negative... and then I think to myself, "What about the entire modern pedal industry?"

[midwayfair]

Saw that, you can tell that Dave has spent no time whatsoever around any pedal nerds. He goes on about how practically no one uses centre-negative... and then I think to myself, "What about the entire modern pedal industry?"

Guitar pedals are a niche product in a niche industry (audio). The reason it has to be center "negative" is that we switch BOTH the ground and positive rails. We allow the battery to connect to the positive rail when the power barrel is unplugged and the battery ground to connect to ground when a mono guitar cable is plugged into a stereo input jack.

I don't think there's anything about the circuit he was looking at that couldn't have been set up to switch the ground instead of the positive.