hmm, am i missing something here? dB is logarithmic. thus a doubling in sound intensity means a 3 dB(A) rise. thus, 13 dB(A) rise should have a sound intensity slightly greater than 16x. hmm... i must be missing some subjective weighting... i do seem to recall that 10x sound intensity means perceived loudness is doubled. let's see if i can recall that...
if i seem to recall correctly, the formula for perceived loudness is something like-
perceived loudness = 0.3 * ( physical sound intensity)
right? then 13 dB sound intensity is a little over 3 dB of perceived loudness. thus, slightly over a doubling of perceived loudness, which is what your were telling me, mike
man... time to look up those equations again. feel free to correct or clarify anything. i'm far from positive on those equations from memory.
sidenote, i checked the fans used in the thg article before post thg to make sure they were both the same. the model number is given in the article for the mcx measurement (TMD 5600 RPM), and the stock fan for the aeroflow is the 5600 RPM TMD according to the vantec sight.
i don't discount that the results may be exaggerated as we aren't told how the noise was measured, but i think we can agree that the vantec is much quieter. 2x quieter? dunno, but i think it's much quieter.
however, rather than turning this into a comparative post, my intention of the post is more for discussion fodder about airflow/heatsink/fan design for low-noise performance rather than so-and-so heatsink A is 2x quieter the so-and-so-heatsink B. heck, your response already helped me to recall how to calculate perceived noise!