The A weighted curve is the inverse of the 40 phon Fletcher-Munson equal loudness curves which were developed in 1933.
It cuts low frequencies a lot - 40 dB at 20 Hz.
40 phons is a very low SPL and not representative of levels we usually listen. As volume increases our hearing ‘flattens our’ and becomes more equally sensitive to tones at different frequencies.
Over time the A curve has been used to measure noise exposure as high frequencies do more hearing damage than low frequencies of similar intensity.
So if you are concerned about noise exposure use the A curve.
If you want to know how much sound power your rig is putting out, use the flatter C weighted curve.
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Main System:
Amati Futura Mains
Amati Homage VOX Center,
Proac Response 1sc Rears,
Three MC2301's for L,C,R
MC 602 for the rears
C 1100, MX 151, MCD 1100, MR 80
Nottingham Dais with Wave Mechanic
Sumiko Palo Santos Presentation
SurfacePro 3, RPi 4, ROON, WW Starlight Platinum USB, Schiit Yggdrasil, Benchmark DAC3 HGC
MX 151, OppO BDP-95, JVC RS-500 DILA projector, 106" diagonal Stewart Luxus Screenwall Deluxe with Studiotek 130 G3 material.
Lake House:
Ohm F, MC 275V, C2300, MR 77, Rega P3
OnDeck:
McIntosh MAC 4300v
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