The anechoic chamber, "Tysta rummet", is an essential part of the Phonetics Laboratory. This is a recording studio designed to completely absorb sound reflections and to be insulated from exterior sources of noise. Thus, it is very silent and has virtually no reflected signals (i.e. room acoustics). We use the anechoic chamber for speech recordings that require highly controlled acoustic conditions approximating so called “free field” conditions.

Studio equipment

The studio is equipped with state-of-the-art microphones and a high quality audio interface. For most recordings, we are using Brüel & Kjær 1/2′′ free-field microphones (Type 4189) with preamplifiers (Type 2669). The microphones are connected to a Brüel & Kjær NEXUS conditioning amplifier (Type 2692), which in turn is connected to a Motu 8M audio interface. We are primarily using the REAPER digital audio workstation software for the recordings.

Recordings

All recording sessions are monitored from the control room outside the anechoic chamber, using a TV monitor showing the subject(s) in the chamber, and via headphones/speakers. In addition, there is an audio intercom system allowing two-way communication between the subject and the experiment leader.

Photo by Lena Katarina Johansson

Our baby lab is specially equipped for studies of babies' language development.

Baby lab

The Breathing Lab provides an unique facility for recording breathing in multiparty conversations. Most recordings involve two or three participants, and we typically record audio, video, and respiratory activity simultaneously from all participants.

Respiratory Inductance Plethysmography (RIP) and other techniques

For the breathing registrations, we use a technique called Respiratory Inductance Plethysmography (RIP). This technique measures the movements resulting from inhalations and exhalations by means of elastic transducer belts worn around the chest and the abdomen. The belts are connected to a RespTrack processor (developed in-house) that transforms the respiratory movements into direct voltages in the range −2V to +2V. These analogue signals are captured by an integrated physiological data acquisition system (PowerLab hardware and LabChart software by ADInstruments). The respiratory volumes and flows can be calibrated in litres by means of a digital spirometer (CareFusion MicroLoop) if needed. Audio is collected using head-worn microphones with a cardioid polar pattern (Sennheiser HSP 4), an audio interface (Motu 8M), and a digital audio workstation (REAPER). Video of each speaker’s head and torso is recorded using GoPro Hero3+ cameras.

At the EEG Lab, we record brain responses to auditory and visual stimuli such as tones, speech sounds, words, written text, pictures, and sign language. We use these event-related potentials (ERPs) to study the neural mechanisms of language and its related faculties of perception, memory, emotion, and attention.

The EEG Lab

The Interaction Lab is a 6 m² sound-attenuated and electromagnetically shielded recording studio with an adjacent control room. The lab is designed for audio and video recordings and can be adapted to many different types of recordings.

Homely environment

The Interaction Lab has softly carpeted floors and natural light from large windows, making it a comfortable recording environment. This makes it suitable for longer recording sessions or recording conditions that aim to resemble a home environment, for example, when recording adult-child interactions. 

Equipment

The Interaction Lab is equipped with three wall-mounted cameras (with adjustable height) and a microphone for capturing sound in the whole room. Additionally, there are three cordless microphones that can be attached on the collar (or on special vests when recording very young children). The recording session can be supervised from the control room on monitors for all cameras and microphones. There are two computers in the control room, one of which is equipped with software for editing audio and video material.

Photo by Stockholm University

The Phonetics Laboratory has advanced workshop facilities. Here, our highly skilled technical staff assist in the development of new research methods and in adjusting the equipment to the requirements of each individual study.

Adjacent to the workshop facilities is a preparation room where subjects and equipment can be prepared for and adapted to experimental procedures.

Photo by Francisco de Lacerda

The Teaching Laboratory has a capacity for up to 30 students. It can be used as a classroom or as a laboratory where students can do experiments in small groups. All computers in the Teaching Lab are equipped with recording capabilities, speech analysis software, and software to run simple perception experiments. The Teaching Lab is used for both teaching and research.

Our specially built laboratory rooms are soundproofed to enable qualified audio recordings. Three rooms in the Phonetics Laboratory have been especially constructed to enable high-quality video recordings.

The Perception lab

This 35 m² soundproof recording studio is intended for audio and video recordings. The room can be adjusted for recordings in a homelike environment or for experiments with more than one subject at a time. The Perception Lab is also equipped for laboratory teaching sessions.

Interaction lab

The Interaction Lab is a sound-attenuated and electromagnetically shielded recording studio with an adjacent control room. The lab is designed for audio and video recordings and can be adapted to many different types of recordings. Read more above under the main heading "Interaction lab".

The Wave Speech Research System is a 3D motion capture system specifically designed for tracking speech-related articulatory orofacial movements. The system uses an electromagnetic field to track and record the tiny movements associated with speech, such as the rising and lowering of the jaw or the protrusion of the lips.

How it works

The speaker is situated within a 50 x 50 x 50 cm area in front of an electromagnetic generator, and does not have to keep still as long as they stay within the given area. Small, lightweight coils are placed on the areas of interest, such as the chin and lips. A sound recording takes place simultaneously and is synchronized with the spatial measurements. The result consists of a file where the movements are expressed as numbers for three dimensions together with a sound file.

The Wave System is presently situated in one of our soundproof video studios, with the benefits of an adjoining control room and with sufficient space in the recording studio for the 3D motion capture system.