The insulation changes the Q factor of the wall and reduces it somewhat. Thus it's resonance characteristic will be milder on an insulated wall vs a non-insulated wall. What is probably of a greater concern is the concrete behind the wall. This will stiffen up that entire wall and thus the energy reflected off of this wall will be greater than that of the opposing wall. Fortunately, most of the difference will be in the lower frequencies where an imbalance is less noticeable. If you wanted to balance out the two walls, double sheetrocking or soundboard and sheetrock would likely come reasonably close to a balance. I would listen first, and see if you find the mild imbalance problematic or not.