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When charging from a vehicle or RV, this should not be an issue since the voltage is typically higher than 12.6v. We might think about replacing the wall ACDC plug with one that outputs about 14v or higher at 3A.
We replaced the AC/DC wall plug with a unit that outputs 15V.
Installation
So, we added a buck converter to the input which drops the voltage to 12.6v to charge the battery and power the speaker. This buck module was simply hot glued to to the bottom of the board.
Added a A switch was added to isolate the battery and to prevent battery drain from the buck converter when not in useparasitic draining of the battery over time.
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And voila, all done and running on battery and it sounds amazing!
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