Hello, I have read that vacuum cleaner makes 70 dBa and earplugs can easily go beyond this. The problem I have is that I can hear my neighbor's vacuum cleaner thru wall easily. But if I set my mp3 player at max (should be around 100dBa according to manufacturer) I can heard this at few meters max. I have also set my earplugs to those 70 dBa (I compared both sounds and set the loudness that is most similar to each other). Still I can hear my vacuum cleaner everywhere in my flat, but my earphones can hardly be heard at a distance of one meter. My question is why I cant hear my earphones as loud as vacuum cleaner if they are supposed to have similar loudness? Thank you.