First, the problem is how you measure SPLs. The measurement will vary greatly according to how you aim the sensing microphone and what type of speaker you are measuring. For example, planar (either electrostatic or electromagnetic) speakers are characteristically different from multi-driver electromagnetic cone speakers in how they do or don’t focus sound. Also, the microphone sensor of your SPL meter may have a very different angle of admittance than mine, etc. Second, what gdaddy wrote would seem to apply to digital components with a volume control that operates in the digital domain. Such volume controls do lose resolution, the more they attenuate. I think it’s because digital volume controls simultaneously reduce the bitrate. Most modern digital gear has been engineered with excess bits, so controlling volume in the digital domain does less or no damage than previous. I am not aware, nor have I ever read that the same applies to an analog volume control. Yes, they attenuate, and yes our hearing acuity for very high and very low frequencies will vary with SPLs according to the Fletcher-Munson curve, but why would you lose "resolution" (except for the extreme frequencies where it is more a matter of detecting their presence with your ears) when attenuating? Also, analog controls may be of many different types. Most common are series, ladder, and shunt types. In a series type control, there are resistors in series that add up to produce the desired level of attenuation. There you may lose some resolution because of noise and inductance inherent to passing the signal through a string of resistors soldered together in series. In a ladder type attenuator, for each level of attenuation there is only one resistor in series and one in parallel with the signal. With a really good ladder attenuator, there ought not to be a problem, Shunt attenuators operate most like ladder types but have some potential issues related to input and output impedance.
Are you operating in the correct SPL window for high-fidelity listening?
We spend hours and hundreds of dollars properly setting up our turntables (or have the dealer do it). Do you spend any time setting the correct db level for listening?
The Fletcher-Munson curves, also known as equal loudness contours, illustrate how human perception of sound loudness changes with frequency and volume. They show that at low volumes, the human ear is less sensitive to very low and very high frequencies, making midrange frequencies seem louder than they are. Conversely, at high volumes, the ear becomes more sensitive to low and high frequencies, making them seem louder. See the ISO 226 standard.
I listen at the volume recording engineers use for mixing: 80 to 85 db. Anyone have any thoughts?
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- 44 posts total
- 44 posts total