Well, first of all, i'm not sure it's called a "resonance box" at all in english terms!
But, just before the intake filter box, there's a black plastic box, connected to a rubber hose:
This box serves as a sound supressor, and has also another function in terms of airflow, but that is way to technical for me to explain! Never mind... but the trick is to physically remove this box. That way, the raw sound from the filterintake is NOT surpressed, and under hard acceleration, the sound is quite familiar to the sound you get from a sportsfilter - no kidding.
The best part is, that it's absolutely free
And if you're concerned about what your service technician will say about it, it's very easy to replace it again, before you take your car in for maintenance/service checks.
I've made a guide to removing it in my gallery, but as it is written in danish, i'll try to explain it for you:
It just takes a little patience to remove the box, because it is fitted to the filterbox with some pins of some sort. But in my car, theres just one screw to remove:
(the screw below the box, located at the arrow to the right, over the rubber hose)
When the screw is removed, just pull the rubber hose off the box, and let it stay attached to the frame for now - you can detach it later.
Then there's the hard part: the box has to be twisted a bit to detach from the filter box. Hard to explain, but it will probably be clear for you, when you do it. Given some patience, and moderate force, it will eventually click of the filterbox. I managed to do it in 5 minutes, some have had a little more difficulties.
Hope this was helpfull!