The present invention is a method or apparatus configured for analyzing a data storage device containing a transducer head positionable adjacent a data storage media surface. First, a defect is detected in a region of the surface. Two or more readback signals are obtained, each received during a respective pass of the transducer head adjacent the defective region. The signals are then combined to define a category for the defective region, either automatically or by visual examination of an image. Preferably, all of the read signals are received from the transducer head while the data storage device remains sealed in a substantially opaque chamber. That way, the media defects of an entire population of data storage devices can be analyzed quickly, disassembling the drives for direct visual analysis only on a selective basis.