A device and method for wellbore inspection comprising a downhole tool. The downhole tool may comprise a wireline, a sensor cartridge, and a plurality of centralizers. The method for detecting defects within a wellbore may comprise inserting a downhole tool into a wellbore, wherein the downhole tool comprises a wireline, a sensor cartridge, and a plurality of centralizers. The method also includes producing an acoustic signal with the plurality of centralizers and recording the acoustic signal with a sensor, wherein the sensor records the acoustic signal within an aperture.