DD sonar

[geezerjo09]

I was just wondering if DD's sonar will hear you less if you go deeper of if there is no difference. For example, at periscope depth, he can hear you from 6 km(i think) off if your engines are not on silent mode. Maybe he only hears you at 5 if you go 100 m deep? And does the game model any difference between going at say 4 knots and going at 10 in terms of noise made? In 0% realism, the sound meter automatically goes red if you go anywhere faster than ahead slow, but is there a difference between doing 5 knots and ten?

Please don't just answer "Of course there is, if your going at 10 knots your making more noise" I know that. I want to know if the game accurately models that.