The speed and quality of distance estimate in movies is purely dramatic effect.
But there is a mean how to do it. You will hear pings, probably even at flank. I mean your active intercept sensor will (as torpedoes especially would use non-audible frequencies because of the small size of their transducers).
Torpedoes would ping back as soon as they receive previous ping return, to have high refresh rate of target's position, which is especially important during final phase of attack.
From that you can estimate torpedo maximum range. If you hear pings spaced by 1 second, it meas the pinger is interested in something not more then 1500 meters away from him. And if you are sure it's you, you have some distance.
And if you check active ping detection screen in DW, you will see it displays interval between pings, so it might be intended this way.
In DW you can also launch UAV or sonobuoys to detect torpedo position rather well.
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