Sonar audio

[speed150mph]

Chazlys right about everything except the submerged contacts,

Listen closely with a submerged contact especially at close range and moderate speed. On the broadband audio you can hear a deep bass kind of sound, very low frequency. It kind of blends with the flow noise unless you listen carefully.

Set yourself up on a close submarine contact, and run the cursor from an empty spot of the ocean and let your ears adjust, then move it to the the contact bearing and you will here a slight low toned hum join the flow noise sound.