Yes, passive can only attenuate sound, so itīs reasonable to use them in attenuating some "ugly" frequency.
When trying to "boost" anything, it only means "attenuate everything else".
Just checked, https://leleivre.com/rf_resonance.html (very useful page) says you are attenuating 658Hz, a midrange frequency if I ever saw one, very reasonable.
That said, active Electronics are so small and low powered (and have been so for decades, just check MM and their LM4250 based preamp) that they become cost effective to use for most everybody.
Cost effective here meaning not price but small space and low power consumption.
LM4250 which is still available is so "economic" on that account that it can be powered by a couple watch/calculator button batteries, if you canīt fit a 9V alkaline anywhere and of course donīt want to route a pocket for it.