I was wondering if you were on here.To follow up the above comments, if one wants reliable numbers for a reasonable investment, then it is the old B&K 2209 or the LD 800 B.
With other SPL set ups, you may or may not get the right numbers and you may have spent money not so wisely
Although extremely expensive, we went with the B&K PULSE system a couple of years back, it is the only COTS digital offering that meets the newest U.S. MIL STD version, that being the MIL-STD 1474E. Which sets very tough requirements for the equipment ( especially the sampling rate ), which the old analog do not meet any more.
Sales director, MIL/LE
Ase Utra sound suppressors