Peter Wright's book (Spycatcher) about his (story of his) adventures reverse engineering the thing is a good read. He had another trick of using simple phasing

Peter Wright's book (Spycatcher) about his (story of his) adventures reverse engineering the thing is a good read. He had another trick of using simple phasing to make cocktail party type problems easier for analysts. Just play it out of phase in each ear and the brain works it out apparently.