Post by beegee on Feb 26, 2021 18:45:47 GMT
How can I (conveniently!) verify the signal-to-noise ratio (relative to 1.0Vrms) specified for a power amplifier when the maker states that the measurement is "A-weighted"?
Yes, I do know what A-weighting implies (see fig. 2.5 of "The Audio Expert"), and I'm aware that I could construct an A-weighting filter (see Elliott Sound Products, sound-au.com/project17.htm) for use with my Fluke 87v AC voltmeter, but I find it hard to believe that everybody does this when they simply want to check the signal-to-noise (re. 1.0Vrms) reading.
What's the general ongoing practice? Do techs generally just resort to the use of the built-in low frequency filter input on their Fluke AC voltmeter? Is there some commercially available accessory probe for voltmeters that approximates A-weighted response? (I can't find any such device.) Is there some reasonably priced (i.e., not Audio Precision) low end means of reading the requisite value (10 µVrms for a s/n ratio = -100 dB)? How does the trade handle this noise measurement when "A-weighted" is referenced?
Yes, I do know what A-weighting implies (see fig. 2.5 of "The Audio Expert"), and I'm aware that I could construct an A-weighting filter (see Elliott Sound Products, sound-au.com/project17.htm) for use with my Fluke 87v AC voltmeter, but I find it hard to believe that everybody does this when they simply want to check the signal-to-noise (re. 1.0Vrms) reading.
What's the general ongoing practice? Do techs generally just resort to the use of the built-in low frequency filter input on their Fluke AC voltmeter? Is there some commercially available accessory probe for voltmeters that approximates A-weighted response? (I can't find any such device.) Is there some reasonably priced (i.e., not Audio Precision) low end means of reading the requisite value (10 µVrms for a s/n ratio = -100 dB)? How does the trade handle this noise measurement when "A-weighted" is referenced?
