It seems that noise reducing headphones have come very far in the past few decades, so how did our cold war crews (including P2V, etc.) cut through the noise? WHAT????
I'm afraid the answer is going to seem a tad trite, perhaps even sarcastic...nevertheless it is the truth, the whole truth and nothing but the truth.
We turned the volume up.
We only had passive (as in sound-proofed) noise reduction. Nothing clever like active noise control...well not in my time anyway (left in 2003).
I would agree totally with YS, even though I think??? lofar just about made it into the Shack?????
FWIW sensor wise, the gap between the last version of the Shack and the Nimrod MR1 was a lot smaller than the gap between the Nimrod MR1 and the Nimrod MR2.