Untangling Canon's asinine use of proprietary connectors in the AC-E6N AC power adapter


EOS 5D Mark IV
CR Pro
Feb 25, 2015
interesting.. one of the customer reviews describes the adaptor affecting the noise floor in every video:

"... Reviewed in Canada on October 23, 2018
Verified Purchase
I bought this for my Canon 5d mkiii in order to power it during longer recording sessions of audio/video demonstrations I'm making. Since these are demonstrations focusing on sound character the audio quality is a priority. I find it most convenient to simply run the audio source to the camera input rather than try to align the audio later in post. After recording several sessions I noticed a ground hum significantly louder than the noise floor in every video. This led me on a very tedious troubleshooting journey that lasted the past two nights. Only after hours and hours today it dawned on me that I should check the power instead of the audio chain. As soon as I put the battery in I had clean audio again repeatedly. Next I tried making sure everything was powered using the same ground reference but it made no difference. Since this power supply renders the camera's audio input useless I must give it one star, but it seems it should work fine strictly for video..."

That's a ground loop, which is something you should always check for when you have something connected both to ground and mains power. It's sadly not so easy to solve, in a on-stage setting you can usually plug every mains power into the same group/phase, but if you're recording from the back of the room with an audio line snaking to the front, you're out of luck.
Feb 12, 2021
Sorry for resurrecting an old thread, but I put together a more elegant solution to this problem that cost very little.

Parts :

Hammond 1551MBK Enclosure - eBay
3.5mm Barrel 2.1mm pin 12V DC Socket - eBay
Schurter 4840.2220 12V DC Socket - Mouser




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