There are two reasons for carrying an audio recorder: for interviews; and for recording ambient audio. People tend to overestimate how often they need an audio recorder, and underestimate how much effort audio requires to be a useful addition to the project. As a rule of thumb every hour of interview recorded takes 6 hours to transcribe.

If you plan to re-use audio in video or presentations then the Sony DCM D-50 is built like a tank, and can pick up the subtlest of sounds to the point that it can help help you hear, and think differently about the city. If you only need to record interviews for transcription then the Olympus WS-21OS does a credible job – it’s small and light, and its built-in USB drive makes transferring files easy. If your aural ergonomics can handle earsphones the Etymotic Research ER6i include a flange that seals the ear with almost-noise-cancelling properties and even works whilst cycling.