Let me repeat again with simpler explanation on this Mic thingy for Black5, so that you guys know what to expect.
Hero4 uses analog input for mic, its pure wire to wire matters. So what the old 3.5mm mic adapter did was... to use a few connections already available on the Hero4 unique 10 connections USB port. USB 2.0 standard is 5 connection only.
So I said that GoPro unique 10 connections USB port is indeed unique. 1 row of 5 pins is USB.Org standard, 1 other row of 5 pins is GoPro own connection, and mic connection is there.
Black5 is totally a different, it does not allow analog simple wire connection for external mic.
It uses a true USB-C standard, and GoPro no more wants its mic adapter to inject analog signal, GoPro wants digital signal because it will create a stand-alone professional WAV file for every video which uses this Pro 3.5mm mic adapter. This thing is not an adapter, it is actually a CONVERTER. Analog to digital converter that is.
This is the flow/connection chart :
Old hero 4
External Mic >>> 3.5mm mic adapter >> mic gets connection to the available pins of the 10 pins unique USB port on camera.
Hero4 then recognized this input and bypass its built in mic and instead uses the external mic feed. Audio remain as stereo, only 2 channel in the MP4 video output of Hero4.
External Mic >>> analog signal >>>Pro 3.5 mm mic adapter/converter >> analog signal converted to digital WAV by the adapter/converter>>>converted to USB-C standard so that it can use the USB-C data path>> camera then detect this WAV file and create a separate extra WAV audio track while its MP4 still has its own audio track. So basically the output MP4 video is still stereo but extra WAV audio file is available for signal from the external mic. This is why this adapter/converter cant be cheap and small as old model adapter, because it has electronics inside it and also can do power injection thru USB-C too.
Well GoPro can actually make a USB-C 3.5mm mic adapter a dummy version like the old one, I am sure but they will load their cam processor more if they want to create that beautiful high end WAV file.
The WAV file Gopro uses is professional specification, no kidding.
It is a PCM Signed 32-bit little-endian, 1024kbps, 48000Hz 4 channels.
So remember and dont think this is wire to wire matters, its much more complex.
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