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Re: World's Most Reverberant RoomBrüel & Kjær (4179) have stuff that is just about able to measure at that level.Brüel & Kjær use narrow band analysis to take the noise floor down further, but just comparative analysis can fairly easily get you useful results 10 dB below the noise floor if the measurement system is stable and consistent enough to establish a baseline noise floor reference.Of course you know, I was just stating the obvious because that fact was pivotal to my argument. ("Remember")
Re: World's Most Reverberant Room
Brüel & Kjær (4179) have stuff that is just about able to measure at that level.
Brüel & Kjær use narrow band analysis to take the noise floor down further, but just comparative analysis can fairly easily get you useful results 10 dB below the noise floor if the measurement system is stable and consistent enough to establish a baseline noise floor reference.
Of course you know, I was just stating the obvious because that fact was pivotal to my argument. ("Remember")