Thats not "VLF on." Its "we fixed the crappy bass response, and now people like it better." They made the bass extension (or frequency content of the audio) look more like what you get with high-end speakers. Not surprisingly, people like it better. I know I would. To be proper, the response should be the same above about 25 Hz for both cases, and then VLF extension added to take it down, to, say 10 Hz or so. That way in both cases the actual audio heard doesn't vary.