(Ninjaed, on the dB(A) bit, but not removing it.)
dB is strictly a comparative measure, in accoustics being (usually) against a standard pressure level reference. If you're measuring the noise from "a thing" then you should be a metre away from it (and/or state what distance you are measuring it at). Measuring a crowd or other conditions within a surrounding background noise is a distanceless thing, and that probably also applies to "in the production office" or "unlucky nearby residents" in that specific locations obviate the need to state distance under the proviso that whatever limits the venue-proper is (or isn't) sticking to, you expect not to be in levels of loud noise outside of the 'allowably more loud' performance area.
dBA, accoustically, is a particular kind of dB SPL with weighted frequency sensitivity, related to the abilities and tolerances of the typical human ear. I think you're really supposed to specify the "A"-weighted dB as dB(A), so as not to make it look like Amp-comparison[1], and there are other weighting-profiles/reinterpretations given other letters/qualifiers.
I think measuring dB(whatever) in a church might be particularly awkward. It's the sort of space designed (by emperical "what works for church music", co-evolving with "what sorts of sounds work best in a church-liks space") to propogate sound, but there is rarely an actual exhaustive process of identifying the sound-transmission and refining it to not produce anomolously loud places or dead-spots. Especially as there's not much room to fiddle with the original structural concept once you've finally enclosed the whole struture with a roof (you can't nudge a structurally necessary but accoustically inconvenient pillar over by a few feet, even if you'd want to), except by adding in soft coverings and/or some relocatable decorative wooden screens. (Or, yes, these days shuffling the PA system and tweaking the levels. But you'd need enough speakers to cover everywhere without dominating any bits straight in front of them or within an inconveniently reinforcing back-corner.)
Modern accoustically-aware performance spaces tend to aim for biasing towards deadness (padded seat undersides, to react to sound similarly when raised as when some fleshy (and, usually, clothed!) audience member has sat in that position) and then infill. That's more for theatres/concert-halls. Your random 'internally Brutalist' nightclub space, essentially a warehouse with any internalised structures being mainly brick-and-breeze-block and the softest ground-level surface generally being wipe-clean wood, except for what little bit of carpet there may be (VIP section only, and not in front of the VIP bar, but still a big eater of carpet-cleaner and wet-vaccing). Absorbant ceiling tiles are an option (maybe... suspended ceilings are dust-traps[2], at hazard from thrown things and should not be a fire-hazard), or even draped fabrics (similar issues), and it's a truly aspirational proprietor who'd make it much more luxurious than that. ...at least from my experience, or maybe I've just lucked out and there are places that are more soft-play area than either laserquest or indoor go-karting spaces.
[1] There are all kinds of dB[X]s, for other measures in (and vs. the baseline of) [X]-units. Like dBV, which indicates voltage-differential comparison (vs 1V, as dBmV would vs 1mV) and dBK which measures 'temperature noise' (against the Kelvin scale degree).
[2] I know this as well as anyone, from my laying of network cables across and through such upper spaces on many occasions. Whether a school classroom or a hotel lounge or an area just off an active kitchen(!), however well looked after the space below is, you poke up into the tiles to guide a cable across it and come down at the very least covered with unidentifiable dust.
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Topic: Things that made you go "WTF?" today o_O (Read 14860445 times)