Safes made prior to 1960 may have discernible tumbler position sound differences.
You can listen to the tumble or sound of a safe as the dial is being spun. The tumblers inside an analog combination safe make a sound as they land in each corresponding position on the dial. Many manufacturers of modern safes have found ways to mask or modify the sounds made by tumblers. These designs are intended to foil would-be safe crackers. Given sufficient time, a knowledgeable locksmith can open antique safes by listening to and feeling the movement of the tumblers.
Instructions
1. Reduce the ambient sound in the room as much as possible. Turn off fans or other electronics. Close windows and doors to eliminate outside noise.
2. Place your hand on the safe dial. Press the hard cartilage flap in front of your ear hole up against the safe door near the dial. Gently press the round outer portion of your ear onto the door so it is barely making contact.
3. Cup the outside of the ear pressed to the door with your other free hand. Use a stethoscope if you are not able to get your ear to the safe door.
4. Turn the dial to the zero position. Twist the safe dial slowly from one position to the next. Listen closely to the clicking sound or tumble coming from the tumbles inside the safe.
Tags: safe dial, safe door
