The academic efforts of the section are highly experimental, and include among other the design and construction of experimental technology platforms, advanced measurements and analysis, and human factors research. A wide range of laboratory facilities are used, including a range of rooms with tailored acoustics (anechoic, reverberant, listening rooms, and booths). Most are developed and administered locally in close collaboration between academic staffs and students, and some have been developed tailored for special purposes (low frequency exposure chamber with plane wave control, pressure chamber) others for high performance computing in various contexts (embedded systems lab, birdnest).
Lab Facilities in SIP
Rent a lab
When not in use for academic purposes, the laboratories can be rented on an hourly basis (minimum one half day), with academic and/or technical supervision (minimum one hour technical assistant). Contact Claus Vestergaard Skipper for options and availability.
The reverberation room is constructed to reflect sound as much as possible, thus it is the acoustic opposite of an anechoic room. For this purpose all the walls, the floor and the ceiling are made from smoothly painted concrete. Reflective slabs make the sound field more diffuse. Due to the hard and rigid surfaces in the room, the sound dies out slowly. At e.g. 100 Hz the reverberation time is as long as 13 seconds. The reverberation room is particularly suitable for measurements of the properties of sound-absorbing materials. In addition, the room is used to determine radiated noise from machines, e.g. washing machines, drills and fans. A pressure field chamber is installed in the corner.
Large Anechoic Room
The large 65 m2 anechoic room is among the most used rooms in the laboratory.
Many acoustical measurements necessitate the use of an anechoic room, e.g. measurements of loudspeakers and microphones. The room is also used for listening experiments.
The walls, ceiling and floor are all covered with sound absorbing wedges so that reflections are avoided. Between the wedges inside the room there is 6.2 m x 5.0 m x 5.8 m, lower cut off frequency approximately 65 Hz.
The room is a double-box construction made of concrete. The inner box (9.1m x 7.9m x 8.7m) is placed on a rubber suspension in order to insulate the room against noise and vibrations from the surroundings. Even when the air-conditioning is on there is no audible background noise in the room.
The Listening room conforms to the IEC 60268-13 standard, which describes an "average living room" acoustically. The reverberation time is thus approximately 0.4 seconds, but this can be adjusted by removing parts of the ceiling or varying the wall materials.
The Listening room is used for both listening tests and measurements. During listening tests the subjects are typically asked to estimate qualities of what they hear, e.g. evaluation of hi-fi loudspeakers or microphone recording techniques.
During a listening test the equipment is often hid behind curtains so that the subjects are not affected by visual impressions. The room is equipped with a set of specially tuned built-in loudspeakers. The room can also be used for studies of sound propagation in an "average living room".
Embedded Systems Lab
SIP hosts laboratory facilities for design, development and test of real-time hardware/software embedded systems. Apart from a huge variety of equipment for test and measurement, the laboratory also holds development tools and platforms for a broad range of FPGAs, DSPs, and MCUs.
Listening Room - multichannel
This 60 m2 listening room conforms to the recommendation ITU-R BS775-1 for multichannel/surround setups (5.1, 8.2 etc.) and also to the standards for rooms used for stereo listening setups, e.g. evaluation of sound quality.
The room is a completely symmetrical double door construction. The reverberation time is variable (reflective/absorbing moveable panels) between approximately 0.2 to 0.4 seconds. The listening room can be used for both listening tests and measurements. It is controlled from Control room Q via e.g. B&K microphone connections, 50 ohm cables, signal/loudspeaker cables and serial data connections.
The B5 section holds two small cabins meant for subjective listening experiments and e.g. speech recording sessions - namely Cabin A and Cabin B.
They are double-door constructions and have sound isolating walls, floor and ceiling. Each room consists of a steel box resting on springs for anti-vibrating purposes.
The acoustic isolation of the rooms is necessary, so that experiments and recordings are not disturbed by noise from the outside.
Pressure Field Chamber
The pressure field chamber is constructed in concrete and bricks and has 3 volumes: A center volume of 1.0 m3 for a human subject and two side volumes of 0.7 m3 acting as loudspeaker enclosures as seen on the drawing. The chamber has been made as small as possible to produce a true pressure field at the highest possible frequency but still large enough to be comfortable for the subject. The room is equipped with eight 13" bass loudspeakers. The chamber is used for presentation of low frequency sounds (20 Hz - 100 Hz) to human test subjects.
BIRDNEST is a heterogeneous computer cluster consisting of the following:
1 x birdnest login-server having 12 physical cores (2 x Intel Xeon E5-2643V3) and 192 GB memory.
1 x goldcrest administration server having 12 physical cores (2 x Intel Xeon E5-2643V3), 192 GB memory 12 x 6 TB Hitachi disks and Intel hardware RAID and battery backup.
5 x eagle computational servers each having 24 physical cores (2 x Intel Xeon E5-2697V2), 384 GB memory and local SSD storage (250 GB + 800 GB).
1 x hawk1 computational server having 40 physical cores (2 x Intel Xeon E7-4850), 384 GB memory and local SSD storage.
1 x vulture1 computational server having 12 physical cores (2 x Intel Xeon X5670), 192 GB memory and local storage (300 GB).
1 x phoenix1 computational server having 8 physical cores (2 x Intel Xeon X5670), 48 GB memory, local storage (300 GB) and 3 x NVIDIA GeForce GTX580 (3 GB).
1 x phoenix2 computational server having 8 physical cores (2 x Intel Xeon X5670), 48 GB memory, local storage (300 GB) and 3 x NVIDIA Tesla C2070 (6 GB).
1 x kestrel computational server having 12 physical cores (2 x Intel Xeon E5-2643V2), 384 GB memory, local SSD storage (250 GB + 800 GB).
The backbone consists of 1 Gb/s Ethernet and 20 Gb/s InfiniBand.
The main computational resource is CPU based with 8-40 physical core computers – far most further have high capacity memory and fast SSD local storage. Two servers include acceleration cards with 3 x NVIDIA GeForce and 3 x NVIDIA Tesla. All servers are tied together via InfiniBand network. One server is dedicated for administration and this also holds 12 state of the art HGST disks each of 6 TB capacity. One server is dedicated for login purposes meaning that all computational resources are protected by this server. AAU-IST hosts the servers and a maintenance/support/performance plan is being followed to ensure robust operation.
Contact: Professor Torben Larsen, Associate Professor Thomas Arildsen and Postdoc Tobias Lindstrøm Jensen.
Small Anechoic Room
This 33 m2 anechoic room is covered with sound absorbing wedges so that reflections are avoided down to approximately 200 Hz. Many acoustical measurements necessitate the use of anechoic surroundings, e.g. measurements of loudspeakers and microphones, however, this anechoic room is specifically designed for human exposures. The room is a double-box construction, and the inner box is placed on a rubber suspension in order to insulate the room against external noise and vibrations. Even when the air-conditioning is on, no audible background noise appears. The wedges inside are made of a foam material. A hoist is placed in the ceiling on which various equipment can be mounted and set in position.
Like the other special rooms in our laboratory, the Audiometry room has sound-isolating walls, floor and ceiling.
The acoustic isolation of rooms next to each other is necessary so that experiments and measurements are not disturbed by noise from the outside.
The walls and ceiling of the Audiometry room are covered by absorbing material, which makes this one of the most "quiet" rooms in the laboratory.
The room was made particularly for audiometric examinations of the subjects and conforms to the ISO 8253-2 standard. The room can also be used for measurements that require only little space and less absorptive surroundings than those found in the anechoic room.