Here is a litte read up on them
Tunable Bass Response
The front side of the machined aluminum back chamber has 8 cylindrical vents to provide awesome bass response. We started with 3 vents and it sounded really good, so we tried 4 vents and the bass got even better. Then we tried 6 vents and things started really bumpin, so we went with 8 vents. Why mess around? In this configuration, the bass is pumpin and bumpin, or thumpin and jumpin or something to that effect.
In this research phase, we found we could tune the bass by altering the amount of vent area. Some people preferred the 3 vents, some 4, some 5 and so on, some liked completely sealed. So rather than use a ‘one size fits all’ mentality, we chose to let people listen in the way they like. There is no best way to sound; everyone has their own way, which is the best way if the way you like to listen is the best way and don’t accept that other peoples’ best way is the best way for you. Say that three times real fast!
http://www.ddproaudio.com/pro3/products ... efault.asp
May be worth a try for 60 bux, but not sure. I do need some new ear buds