The JBL stated +- 3 db which means their response can be off by 6 db from 1 frequency to another, which is about what your are going to get from a respectable speaker.
Did the Podiums state +- dbs?
If the mentione +- 10db, there can be a 2- db difference from frequencies, so specs are helpful only if they are all on a even playing field, most companies know how to use specs to make their so so product look incredible onpaper.
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