Duplicate cylinder tests (CYLEX) have been run on PBX 9502 and LX-17. The 95% error in the absolute value of the derived detonation energy density is about +/- 1% whereas the 95% error of the difference error is +/- 0.5% or better. The analytic model has been upgraded with a better strain description. The effect of the air gap between a pressed solid explosive and the inner copper wall has been measured and modeled. An off-center effect has also been seen. Density effects on the energy density from 1.82 to 1.92 g cm(-3) are described for LX-17. Data has also been taken at -55, 75 and 125 degrees C. The last temperature gives a large enough difference to show that the mechanism appears to be only density change.