QUOTE(windboy @ Jun 29 2012, 02:23 PM)
i think so, they stated to reduce unwanted air resonance, maybe to reproduce live sound effect?
A myth
QUOTE(walabies @ Jul 2 2012, 08:00 PM)
My guessing is that when the air moves 'balance-ly'. It will imitate how the music to be reproduced, and what is hard to achieve is 'da balance'. Two driver which is symmetrical.
You both have a good point. They don't really explain the term all that much, but my guess is that it's to avoid, what windboy quoted from FAD, unwanted resonance, and what walabies is saying, to enable it to reproduce the music truly (well, maybe also allow them to tune the sound intricately to how they want it).
The driver will also produce sound behind it in the shell. If the sound and condition is right certain frequency can resonate and amplify, making the sound artificial as if you've applied an EQ and boosted that frequency. Or the sound wave can be reflected back into the true sound wave at the same phase, but inverted, thus cancelling it. All these can also happen in the frequency range beyond the human hearing, so while we can't hear them, maybe the sonic 'tingling' or 'feel' is compromised. The ports on an FAD monitor is probably to eliminate unwanted pressure wave/back pressure inside the shell. Works to eliminate wave cancellation and resonance. Maybe what makes it special in FAD is the the BAM allows intricate sound tuning, possibly greater isolation than open back, most probably allow the shell to virtually 'disappear' as far as the driver is concerned so no colouration due to said resonance and wave cancellation.
Again, this is my theory.
This post has been edited by tunertoobe: Jul 2 2012, 09:04 PM