Quote:
Originally Posted by W9TR
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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Who knew I'd need that physics 101 class I constantly cut back in college? Thanks, this is a very helpful addition to Ivan & Serge's replies. And yes, I'm mainly concerned about protecting what's left of my old ears!
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SF Stradivari, Aric Audio Motherlode XL preamp and Super KT Parallel amps; Pass XP 27, Raven One TT, Graham Phantom II arm, Lyra Etna Lamda, Airtight PC1, Bryston 3.14 DAC, Transparent Reference & Wireworld, dedicated treated room 17 X 34 X 9
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