Removing Reflections in Semianechoic Impulse Responses by Frequency-Dependent Truncation

Denk F, Kollmeier B, Ewert SD. Removing Reflections in Semianechoic Impulse Responses by Frequency-Dependent Truncation. J Audio Eng Soc. 2018;66(3):146-153. doi:10.17743/jaes.2018.0002

@article{Denk2018_19382,
  author = {Denk, Florian and Kollmeier, Birger and Ewert, Stephan D.},
  title = {{Removing Reflections in Semianechoic Impulse Responses by Frequency-Dependent Truncation}},
  journal = {Journal of the Audio Engineering Society},
  volume = {66},
  number = {3},
  pages = {146--153},
  year = {2018},
  month = mar,
  publisher = {Audio Engineering Society},
  doi = {10.17743/jaes.2018.0002},
  url = {https://doi.org/10.17743/jaes.2018.0002}
}

TY  - JOUR
TI  - Removing Reflections in Semianechoic Impulse Responses by Frequency-Dependent Truncation
AU  - Denk, Florian
AU  - Kollmeier, Birger
AU  - Ewert, Stephan D.
T2  - Journal of the Audio Engineering Society
J2  - J. Audio Eng. Soc.
VL  - 66
IS  - 3
SP  - 146
EP  - 153
PY  - 2018
DA  - 2018/03/06
DO  - 10.17743/jaes.2018.0002
UR  - https://doi.org/10.17743/jaes.2018.0002
PB  - Audio Engineering Society
LA  - en
AB  - Acoustic reflections in impulse responses can be eliminated by truncation to short observation times that exclude the reflections. However, truncating the response tail distorts the corresponding low-frequency transfer function. When reflections in ”semianechoic” data originate from moderate-sized objects, e.g., equipment in anechoic chambers, their composition is mostly high frequencies. Consequently, truncation must only be performed in the mid to high frequencies where the information is contained in a brief time interval; the impulse response tail is anechoic for the low frequencies and can be retained. The authors present a frequency-dependent truncation approach that exploits this property by adapting the truncation length in each band. This avoids low-frequency errors while disturbing reflections are windowed out. Among several tested formulations, a novel Short Time Fourier Transform-based formulation generated the least artifacts while the anechoic impulse response was well preserved in both simulated and measured semianechoic data.
ER  -