Ah... my fault bad night time calculations
, I meant 19.2v 2100mah thats still a long run time. Ive gotten over 16 hours on that set up. Still pretty good and I know you could get 9.6v batteries with a larger amount of mah.
Ok here is the equation for calculating run time ( Battery Capacity [mAH] / Current Draw [mA] ) * ( .80 )
So technically speaking (2100[mAH]/80[mA])*(.80)=21hrs
Im not positive that the sax pulls 80mA but thats what I read on the oade boards archive(I believe, it has been a while) and it says on the Sonosax website the power requirments are
External:12V DC to 24V DC, minimum 30mA, maximum 80mA
So I assumed that 80mA could be its maximum draw, Im sure some one will correct me if its wrong
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Now I just started playing with these batteries before this I ran 19.2v 1000mah bats it wasnt until recently (this summer) that I added the bats with larger mah. The last time I ran them was the longest and it was over 16hrs for a July 4th festival. So I cant really tell for sure what the max runtime will be with this setup but its way better than using regular 9v batts.