Strong acoustical aberrations such as induced by multi-mode waveguides or the human skull can significantly reduce the quality of or prevent effective ultrasound-based imaging. We propose a novel non-invasive calibration method that utilizes two independent acoustical accesses and a time reversal virtual array (TRVA) for adaptive wavefront correction. Numerical characterization and a model experiment utilizing this method show an improvement of the lateral resolution and the peak to background ratio by up to 35% and 10% respectively.