If you go to
http://hnsa.org/sound/#i52wire then you can hear actual recordings taken from sonobuoys of an attack upon the Japanese sub I52.
It also has a lot of detail about other sounds used for WW2 sonobuoy/hydrophone operators - such things as slamming hatches, pumps running etc.
Very interesting site, apologies to all if this has already been posted (too lazy to do a search).