The battery pack is as discussed in the introduction a 3S4P lithium homemade pack.
It gives 12.6V fully charged and 12000mah of capacity.
The pack is soldered the clean way with a DIY point soldering unit I've made for making some powerfull eBikes.
The rig will have also an external port to connect a power supply to supply only the PA PWR for the finals.
As discussed here, I'll give it a go to test suppliyng more voltage for the finals and see if there are improvements.
It seems that the max voltage you can supply without damaging the board is about 20V. So I plan to test it maybe at 19-20V and see.