DOI: 10.5281/zenodo.14938786
title: RWTH IKS Lab Eigenmike em64 Impulse Response Database

description: NOTE: We refer readers to the newer version of this database, where it has been made possible to download documentation and some exemplary room impulse responses separately from the entire dataset.

This room impulse response database was created by the Institute of Communication Systems (IKS) and the Institute for Hearing Technology and Acoustics (IHTA) at RWTH Aachen University (Germany).

Measurement Setup

The measurements were conducted in the IKS|Lab of the Institute of Communication Systems (IKS) at RWTH Aachen University. This room complies with the ITU-R BS.1116-3 recommendation by featuring a reverberation time of approximately T60 ≈ 0.25 s. The room impulse responses were measured using the mh acoustics Eigenmike em64 spherical microphone array. 

Loudspeaker Arrangement

The IKS|Lab consists of 36 spherically arranged Neumann KH120D studio monitors, 32 of which are in a spherical arrangement. These loudspeakers are positioned on four different height levels. Specifically, there are 14 speakers at a height of 1.15 m from the floor on the middle level, 12 speakers at a height of 2.15 m from the floor on the upper level, 5 speakers at a height of 0.25 m from the floor on the ground level, and 5 speakers at a height of 2.7 m from the floor on the ceiling. The distance from the center of the room to each speaker is 1.6 m. Additionally, 4 loudspeakers are arranged on the ceiling in a circle with a radius of 1.2 m around the ceiling loudspeaker that is located on the sphere. The distance between the center and these 4 loudspeakers is 1.9 m.

Measurement Procedure

The room impulse responses were measured at 63 different positions. At each position, a logarithmic sweep signal with length of 10 second was played back by each of the 36 loudspeakers and recorded at the 64 channels of the microphone array, which yields 36 x 63 = 2268 source-receiver combinations and 2268 x 64 = 145152 room impulse responses in total. The measured room impulse responses were truncated to 1 second at a sampling rate of 48 kHz. The 63 microphone positions are distributed across three different height levels. Each height level contains 21 measurement positions arranged in a 5 × 5 rectangular grid, except for the corner positions. These were excluded because they are very close to some of the loudspeakers, which makes reasonable measurements difficult. 

Folder Structure

In the folder em64, there are 63 subfolders, where each subfolder IR_xyz uses the naming convention xyz, with the indices denoting the microphone array position. In each subfolder IR_xyz, there are 36 .mat files from speaker_1.mat to speaker_36.mat, where each file name indicates the loudspeaker index and contains the 64-channel room impulse responses between the microphone array position xyz and the corresponding loudspeaker.

For a more detailed explanation, we refer the reader to the documentation that is part of the published data.

This database was presented in the 51st Annual Meeting on Acoustics (DAS|DAGA). If you wish to use the database in your research, please cite the corresponding paper as:

Chatzimoustafa, E., Heck, J., Patek, D., Jax, P., "A Comprehensive Room Impulse Response Database for Spatial Audio", in Proceedings of the 51st Annual Meeting on Acoustics (DAS|DAGA), Copenhagen, Denmark, March 2025.