Air in any flow system will resonate. That is why the exhaust and headers must be a particular size. They will hurt performance in one area and help it in another according to rpms or exhaust pulses, etc. The same thing holds for intake airbox volume. Sportbikes have tuned with this for many years. Formula racing as well. Even though the turbo is sucking the air, it still has to fight the restrictions. That is what an air intake does, reduce the restriction. The resonator will let the intake volume match what the engineers wanted to create a beneficial resonation in the air to feed the turbo a little better at a certain speed, rpm, whatever. By removing it, you eliminate that effect, but with modified intake and exhaust, etc. you are changing where the improved effect is anyways. All of this is very slight, though.