"being only applicable to low levels so that it tends to devalue the effects of low frequency noise in particular"

Yep - which is WHY the Toowoomba Regional Council finally agreed after enormous pressure to accept dBC for music (with highly boosted bass eg 'Rock'). Of course it did require much faffing around like the mating of elephants, including having a State Attorney General resign shortly after having passed the buck to the State Environmental minister - she replied in a very condescending way that my 'concerns were needless as the dBA scale measured music of all frequencies, not just in the musical scale of C' ... !!!!!! I'm not making this shit up! That poor lady did seem to be a little politically accident prone though ...

There was the time I went to buy a 'weather gauge' gadget with combined temp, humidity and atmosphere pressure gadgets. Noticed that none of the readings on any of the items for sale were near each other - "those ones are still sealed in the plastic bags sir" .... open bags sealed with a bit of sticky tape - didn't buy one !!!!"

The sound info you have 'discovered' was not unhelpful during the battle ... :-) The Council 'chief sound engineer' did accept that dBA threw away a massive amount of the low frequency sound energy compared with dBC, the graphs were most helpful.

JiK was also of great assistance - it was interesting to know that pure 600 Hz at 40 dBA will ripple your coffee ..:-)

It was also interesting to find out that HF dissipates rapidly, whereas LF tends to 'flow along the ground' like an earthquake ... :-)

Trying to compare dBA with dBC especially for 'rock' with highly boosted bass is 'educational' ... :-)

The 'sound clowns' for this local event also do the 'carols by candlelight' with hysterical results. The sound for the prerecorded or live 'thumper musos' is enough to blast you out of your seats (why do you need a dozen mics on a drum kit?!!! - BALANCE!!!! the turn the bloody instrument amps down mate!!!), but when they then try to use a single long throw overhead mic to capture the 100+ voice choirs ... eh? what? can you you turn them up mate? can't hear them. what's that howling noise?

This same park hosts many other community events. Did you know that a dozen muskets doing 'rotating fire' drills (standing fire, kneel, reload, while the next wave walks thru, then fires, etc) can not be heard any where as far as the 'Easter amped up musos', and barely outside the park? A 'drug free event' - yet why are they loudly staggering all over town throwing up? Maybe they had too much 'Spirit of the Lord' ...

Did you know that when a symphony orchestra has to share the stage with 'rock thumpers', that the SO tech does the sound set up? (If we don't do it, we don't turn up!) And then the rockies say that they have never had better sound? :-)

Sigh ...