Bob,
You're probably right. I did notice, however, that the use of the term "subsonic" is actually quite pervasive in audio nomenclature when discussing rumble-related issues (I did a search on the internet for "subsonic filter"). It often seems to be used interchangeably with "infrasonic," which I agree is a more correct term. I wonder if the use originated together with the term "sub"/"subwoofer" and then caught on.
You're probably right. I did notice, however, that the use of the term "subsonic" is actually quite pervasive in audio nomenclature when discussing rumble-related issues (I did a search on the internet for "subsonic filter"). It often seems to be used interchangeably with "infrasonic," which I agree is a more correct term. I wonder if the use originated together with the term "sub"/"subwoofer" and then caught on.