I believe it does. Sounds seem to be louder and I can detect prop sounds at greater distance. Combine that with qualified PO's and you can pick up more contacts when running submerged.
I also echo the advice of others: Do not upgrade anything on the boat before the first patrol of a new career. You can add crewmen and change your torpedoes, but don't add anything else, including a sub emblem. The possible result is the loss of credit for all ships sunk during that first patrol. Be patient and wait for the beginning of your second patrol to tweak your boat. It's a long known game bug that can't be worked around.
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