Now we know the battery used...
As expected no built-in boost in the battery module (might be cheaper than Bose). I hope the voltage converter is inside the box... Or it will not be as loud when battery powered.
so we have inside 2x4 3.7V 3050mAh Li-ion cells
It's a zoom from Thoman a website's picture
I turn the picture counter clockwise so it is easier to read
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Martin 00-18V Goldplus + internal mic (2003)
Martin OM-28V + HFN + internal mic (1999)
Eastman E6OM (2019) Trance Audio Amulet
Yamaha FGX-412 (1998)
Gibson Les Paul Standard 1958 Reissue (2013)
Fender Stratocaster American Vintage 1954 (2014)
http://acousticir.free.fr/