All recordings were made in a quasi-soundproof room in the ECR Lab of the Engineering Department. This `quiet room' measured five metres by five metres. The room was closed off by double doors during recordings and its windows are double-glazed. Fresh air was blown in through sound-trapped ventilation.
Speakers sat on a chair in front of a desk. A fan-free workstation monitor that displayed the prompt texts was on the desk, along with the workstation keyboard and mouse. The actual workstation base-unit was placed outside the room to eliminate fan noise. The far-field desk microphone and a pre-amplifier for the close-talking microphone were placed to the left of the speaker. The close-talking microphone was attached to a pair of headphones which were worn by the speaker. The entire interactive recording process was co-ordinated by clicking on buttons on the workstation screen. More details of this procedure can be found in the recording session section of this report.