INTERVIEW BY SIMON GUERRIER
The Doctor and Felicity (Alice Hewkin) investigate strange noises.
Harry (Colin Ryan) and the Doctor (Peter Capaldi) explore the Landlord’s house in Knock Knock (2017).
The Landlord (David Suchet) hits the right note with his tuning fork.
Soon after Knock Knock was broadcast on 6 May 2017, a special ‘binaural’ version was made available on the BBC’s iPlayer service. This version is included on The Complete Series 10 DVD and Blu-ray box sets. Binaural sound offers a more immersive, engaging experience. Chris Pike, a senior scientist working in audio for BBC Research & Development, explained the technology in a blog post: “The sounds we hear are affected by the shape of our head and ears,” he said, “and the effect varies with the position of the sound source. Our auditory systems can recognise these patterns to localise sounds, particularly frequency-dependent time and level differences between the ears.”