floor joist dead load limits

huangyhg

floor joist dead load limits
i am trying to figure out the maximum psf dead load i can put on 2"x10" floor joists that are 16" on center. the span is 25 linear feet with a load bearing wall running down the center (which makes the true span 12.5 linear feet?)the floor was built 100 years ago so the lumber is actual 2"x10" and very, very, dense. i am trying to put some acoustical upgrades to the floor and shooting for a max total dead load of 25 psf which includes all flooring, subflooring, underlayments, and the ceiling materials underneath the flooring. oh, by the way, the exterior walls are true brick/stone with balloon framing (if that information is helpful?)
what is you live load?
check site:
the live load capacity i am shooting for is 60 psf, but 40 psf should suffice.
sclay, with a dense pine 2x10 @ 16" oc, ll=60 psf, dl=25 psf, def limit l/360, double span 12'6" each.  
the bending stress is ~790psi and def~.2
so the flood joists should be good
assume connection ans bearing have been checked