Sehr geehrte Abonnenten des Kolloquium-Newsletters,
am
Freitag, 20.07.2018
ist einer der nächsten Termine für das Akustische Kolloquium am Institut
für Technische Akustik der RWTH Aachen.
*Termin*
*Vortragende* *Titel*
20.07.2018, 10:30 Henry Hasti
/UROP-Student//////
/
<http://www.akustik.rwth-aachen.de/cms/Technische-Akustik/Das-Institut/Aktue…>
How much does the sound field in auditoria change from one position to
the next?
<http://www.akustik.rwth-aachen.de/cms/Technische-Akustik/Das-Institut/Aktue…>
20.07.2018 11:00
Matthias Reffgen
/MSc-Student/
Untersuchungen zur Kopfhörerwiedergabe mittels individueller und
nicht-individueller HRTFs
<http://www.akustik.rwth-aachen.de/cms/Technische-Akustik/Das-Institut/Aktue…>
Die Vorträge werden im Seminarraum des Instituts (Kopernikusstraße 5)
gehalten.
Zusammenfassung:
*How much does the sound field in auditoria change from one position
to the next?* by Henry Hasti
Despite being a noble planning goal, designing an auditorium with
equally good listening positions throughout entire audience areas is
a target difficult to achieve. In practice, the acoustic conditions
within an auditorium usually span a wide range of values. Knowing
which range is "normal" will help acousticians to learn how
accurately they need to design concert halls. Also it will help to
understand how accurate acoustical measurements in rooms need to be.
This question can be answered when sound fields in auditoria have
been measured in detail and the changes from one position to the
other can be analysed. A robot has been built that is capable of
doing such measurements autonomously. In this project the acoustics
of a concert hall and an orchestra rehearsal room were surveyed
using the robotic array device. The data was analyzed to look at how
acoustic parameters vary throughout performance spaces under
different conditions.
*Untersuchungen zur Kopfhörerwiedergabe mittels individueller und
nicht-individueller HRTFs* von Matthias Reffgen
Aktuell ist der Einsatz der binauralen Geräuschsynthese im Bereich
der Erzeugung von auditiven virtuellen Welten in vielfältigen
Anwendungskontexten von besonderem Interesse. Dabei fokussieren
diverse Studien auf die präzise Bestimmung von individuellen
kopfbezogenen Übertragungsfunktionen (HRTF), die Ermittlung von
anthropometrischen Daten sowie deren Einflüsse im Zeit- und
Frequenzbereich. Alternativ nähern verschiedene Verfahren basierend
auf vereinfachten geometrischen Modellen spezifische individuelle
kopfbezogene Übertragungsfunktionen an, um den messtechnischen
Aufwand zur Bestimmung individueller HRTFs zu reduzieren. Dies
erscheint für eine kommerzielle Verbreitung der Binauraltechnik
elementar.
Zur Beurteilung der Performanz verschiedener Individualisierungen
wurden bekannte und neue analoge Untersuchungsverfahren zur
Durchführung mittels Head-Mounted-Displays implementiert und im
Rahmen mehrerer Hörversuche verwendet. Hierbei wurden neben
individualiserenden Faktoren wie Kopfhörerentzerrung oder
ITD-Anpassung auch der Einfluss ergänzend präsentierter visueller
Stimuli sowie die Einsatzmöglichkeiten von Head-Mounted-Displays zur
Realisierung von Hörversuchen betrachtet.
Die Ergebnisse dieser Untersuchungen sollen zur Beurteilung der
Einsatzmöglichkeiten binauraler Techniken in
nicht-wissenschaftlichen, multimedialen Kontexten verwendet werden.
Für Fragen oder Kommentare stehe ich Ihnen gerne zur Verfügung.
Mit freundlichen Grüßen,
Ingo Witew
--
Dipl.-Ing. Ingo Witew
Research Assistant
ITA - Institute of Technical Acoustics
RWTH Aachen University
Kopernikusstr. 5
52074 Aachen, Germany
Tel +49 241 80-97994
Mobile +49 175 52 37 536
Fax +49 241 80-92214
Ingo.Witew(a)akustik.rwth-aachen.de
http://www.akustik.rwth-aachen.de
Sehr geehrte Abonnenten des Kolloquium-Newsletters,
am
Freitag, 13.07.2018
ist einer der nächsten Termine für das Akustische Kolloquium am Institut
für Technische Akustik der RWTH Aachen.
*Termin*
*Vortragender* *Titel*
13.07.2018, 11:00 Pascal Palenda
/BSc-Student//////
/ Continuous measurement of room impulse responses with Spherical
Loudspeaker Arrays
<http://www.akustik.rwth-aachen.de/cms/Technische-Akustik/Das-Institut/Aktue…>
Der Vortrag wird im Seminarraum des Instituts (Kopernikusstraße 5)
gehalten.
Zusammenfassung:
In the field of acoustics the result of a room impulse response
(RIR) measurement is used for auralization, room reflection analysis
and sound field analysis. When measuring a single RIR, the source
and the receiver, have a directivity which influences the
measurement. If a set of RIRs for different spatial directions is
measured, we obtain a directional room impulse response (DRIR). If
only one loudspeaker is used, a sequential measurement method can be
employed, resulting in a virtual loudspeaker array. However, a
sequential measurement results in a long measurement duration, as
the loudspeaker has to be moved to the different orientations. One
has to consider the time for starting and stopping. If a real
loudspeaker array is used, the measurement duration can be reduced.
However, to achieve the high spatial resolution, the loudspeaker
array still has to be rotated.
The goal is to minimize the time to complete a DRIR measurement. A
proposed way is doing continuous measurements. For this method the
source is rotated continuously. RIRs for different spatial
directions, corresponding to the sequential measuring direction, can
then be extracted from the captured signal. The continuous rotation
eliminates the time for starting and stopping at the desired
orientations. Further decreasing the measurement duration. However,
the continuous rotation introduces further variables which have to
be considered.
This thesis examines the viability and limitations of continuous
measurements for DRIR measurements. To evaluate the influence of the
continuous rotation, different rotation speeds are used.
Additionally, the measured room was varied in its reverberation
time. Different excitation signals are used to measure a room using
a measurement set-up with an spherical loudspeaker array. The RIRs
are then recovered using different algorithms. The results of the
continuous measurements are compared to the sequential measurements.
The different algorithms, excitation signals and rotation speeds are
compared against each other to find the preferred choice.
Für Fragen oder Kommentare stehe ich Ihnen gerne zur Verfügung.
Mit freundlichen Grüßen,
Ingo Witew
--
Dipl.-Ing. Ingo Witew
Research Assistant
ITA - Institute of Technical Acoustics
RWTH Aachen University
Kopernikusstr. 5
52074 Aachen, Germany
Tel +49 241 80-97994
Mobile +49 175 52 37 536
Fax +49 241 80-92214
Ingo.Witew(a)akustik.rwth-aachen.de
http://www.akustik.rwth-aachen.de
Sehr geehrte Abonnenten des Kolloquium-Newsletters,
am
Freitag, 13.07.2018
ist einer der nächsten Termine für das Akustische Kolloquium am Institut
für Technische Akustik der RWTH Aachen.
*Termin*
*Vortragender* *Titel*
13.07.2018, 11:00 Pascal Palenda
/BSc-Student//////
/ Continuous measurement of room impulse responses with Spherical
Loudspeaker Arrays
<http://www.akustik.rwth-aachen.de/cms/Technische-Akustik/Das-Institut/Aktue…>
Der Vortrag wird im Seminarraum des Instituts (Kopernikusstraße 5)
gehalten.
Zusammenfassung:
In the field of acoustics the result of a room impulse response
(RIR) measurement is used for auralization, room reflection analysis
and sound field analysis. When measuring a single RIR, the source
and the receiver, have a directivity which influences the
measurement. If a set of RIRs for different spatial directions is
measured, we obtain a directional room impulse response (DRIR). If
only one loudspeaker is used, a sequential measurement method can be
employed, resulting in a virtual loudspeaker array. However, a
sequential measurement results in a long measurement duration, as
the loudspeaker has to be moved to the different orientations. One
has to consider the time for starting and stopping. If a real
loudspeaker array is used, the measurement duration can be reduced.
However, to achieve the high spatial resolution, the loudspeaker
array still has to be rotated.
The goal is to minimize the time to complete a DRIR measurement. A
proposed way is doing continuous measurements. For this method the
source is rotated continuously. RIRs for different spatial
directions, corresponding to the sequential measuring direction, can
then be extracted from the captured signal. The continuous rotation
eliminates the time for starting and stopping at the desired
orientations. Further decreasing the measurement duration. However,
the continuous rotation introduces further variables which have to
be considered.
This thesis examines the viability and limitations of continuous
measurements for DRIR measurements. To evaluate the influence of the
continuous rotation, different rotation speeds are used.
Additionally, the measured room was varied in its reverberation
time. Different excitation signals are used to measure a room using
a measurement set-up with an spherical loudspeaker array. The RIRs
are then recovered using different algorithms. The results of the
continuous measurements are compared to the sequential measurements.
The different algorithms, excitation signals and rotation speeds are
compared against each other to find the preferred choice.
Für Fragen oder Kommentare stehe ich Ihnen gerne zur Verfügung.
Mit freundlichen Grüßen,
Ingo Witew
--
Dipl.-Ing. Ingo Witew
Research Assistant
ITA - Institute of Technical Acoustics
RWTH Aachen University
Kopernikusstr. 5
52074 Aachen, Germany
Tel +49 241 80-97994
Mobile +49 175 52 37 536
Fax +49 241 80-92214
Ingo.Witew(a)akustik.rwth-aachen.de
http://www.akustik.rwth-aachen.de
