Scientific & Engineering Papers

2023

Comparing Derivations from the Revised Theory of Sound Level Distribution in Rooms to Measurement Results (presented at DAGA 2023)

There is still room to improve accuracy of calculating basic room acoustic parameters using simple equations. The paper takes a view on the evolution of equations to calculate sound pressure level vs. distance and introduces improvements to revised theory equations. By using the energy decay curve template, parameters like EDT10 or T20 can be calculated and thus become comparable to measured counterparts at last. A normalization of lengths to the square root of total surface area allows a different form of equations. These equations prove, that rooms shall be categorized by shape and then scaled by total surface area, not by volume. An inverse application of these equations can estimate 'apparent' V, S, l (mpf), Q and Lw from measured sound pressure levels only. Deviation of apparent and real values will then indicate problematic measurements points or outlying measurement data.

2021

Examples of constraint-based specification of room acoustic parameters (EuroNoise 2021)

An overview of aspects (e.g. room dimension ratios for reverberation time or even low frequency response, minimum required scattering) that can guide or constraint room acoustic specifications.

Room acoustic parameters - What's Up? (AAAA 2021)

An invited paper, presenting an overview on intriguing questions answered and still unanswered in room acoustics practice.

Validation of a New Acoustic Modelling Software (AAAA2021)

An overview of difficulties and aspects of validation the authors faced while developing a room acoustic modelling software PETRA.

Effects of directivity on the field of random sound source distributions (AAAA2021)

2020

An update to the FA2020 paper. The paper investigates properties of random source constellations with interesting analogies.

Investigating properties of random sound source constellations (FA2020)

Often position and aiming of acoustic sources are not exactly known (crowd noise, traffic etc.). A Monte-Carlo model gives interesting and seemingly important, useful results.

Exploring an alternative scheme of room acoustics specification (FA2020)

The paper looks at the problem, that there seems to be a lack of consensus on the methods and forms, optimum values of room acoustic specifications.

2017

'A Comprehensive Approach to Venue Design and Management Creating Experiences' presented at World Stadium Congree, Doha,
about usual PA specifications in stadiums vs. real requirements, physical constraints; how specifications could be made reasonable, how PA system be more than just a way to communicate. Author: Andor T. Fürjes, co K. Molnár)

2014

Prediction of noise of the stations of the new Budapest metro line M4

New Budapest metro line M4 as a case study of efforts in acoustic design.

2005

'Application of Inverse Methods in Room Acoustics' Presented at Forum Acusticum '05,
about the use and basics of the inverse approach. Summary: detailed and scaleable analysis without the usual trial-and-error engineering scheme. Author: Andor T. Fürjes (paper, presentation)

2004

'Using Auralisation as a Tool for Subjective Evaluation' Presented at CFA/DAGA'04,
about the use of auralisation and inverse methods to compare different room configurations. This paper presented our first HRTF-based auralisation together with the MatLab based beam-tracing algorithm that does not need a full recalculation when a modelling parameter (exluding geometry of course, but including diffusity) is changed. Auralisation works in 2D already and the EDC-fitting procedure proved to be useful again. Authors: Andor T. Fürjes, Éva Arató Borsi, Fülöp Augusztinovicz (paper, presentation)

2003

'Investigation of Objective Parameters Correlating with Subjective Impression in Studio Spaces' Presented in Bilbao 2000,
about the results of a subjective test, their correlation to objective measurable parameters. This presentation introduced the EDC contour plot in addition to our earlier results. Authors: Andor T. Fürjes and Éva Arató Borsi. (paper, presentation)

2000

'Design, Measurement and Prediction of Sound Quality in Rooms' Presented in Braunschweig in 2000,
about the inverse method, the EDC fitting method and the room 'potential' for comparison of different room geometries and source-receiver configurations. Author: Andor T. Fürjes (presentation)

'A New Approach to Design Control Rooms and Studios' Presented at AES'00,
about evaluation of different room acoustic environments by their acoustical 'potential', ie. what range of values can be achieved of different EDC based room acoustical parameters by varying absorption and diffusion in different 'classic' control room layouts. The method is based on the inverse approach. The results proved what experience have shown and more... Author: Andor T. Fürjes (paper, presentation)

'A New Method for the Objective Qualification of Rooms' Published in Acta Acustica,
about an efficient way of qualification of rooms, by means of inverse acoustic calculations, EDC prototype fitting, etc. Author: Andor T. Fürjes (paper)

1999

'Solving Acoustical Problems Using the Laplace-Transformation' Research report,
about a new analytical approach to the wave equation to eliminate the problems of conventional steady-state (Fourier, etc.) solutions that neglect transients. Original ideas and support from Mrs. Orsolya Ferencz Erhardt, who applied the same method for electromagnetic fields. Author: Andor T. Fürjes (note)

'Evaluation and Design of Small Rooms' Published in Building Acoustics,
about the subjective evaluation tests, design and modelling issues of small rooms in general. Authors: Andor T. Fürjes, Éva Arató Borsi, Fülöp Augusztinovicz, (paper 228kB pdf)

'Evaluation and Modelling of Small Rooms' Presented at Forum Acusticum 2000,
about the subjective evaluation tests, design and modelling issues of small rooms in general. Authors: Andor T. Fürjes, Éva Arató Borsi, Fülöp Augusztinovicz, Tamás Póth (paper 170kB pdf, presentation 191kB pdf)

'Validation of Geometrical Room Acoustics Algorithms by Comparing Predicted and Measured Room Responses' Presented at ISMA Leuven,
about a fairly new way of thinking about validation of room acoustical models. This is the first paper about the inverse room acoustic method. Authors: Andor T. Fürjes, Éva Arató Borsi, Fülöp Augusztinovicz, Tamás Póth, (paper, presentation)

'Investigations of Acoustical Properties for a Studio Designed by Békésy' Presented at the Békésy Conference about the studio designed by Békésy for the Hungarian National Radio in 1935.
Authors: Éva Arató Borsi, Andor T. Fürjes (paper 244kB pdf, presentation 160kB pdf)

'Methods for Designing Room Acoustics in the Past and in the Future'
Presented at the Békésy Conference about the evolving methods of designing. Authors: Andor T. Fürjes and Éva Arató Borsi (paper, presentation)

'Investigation of Listening Conditions for Multichannel Sound Systems' Presented at AES'99
about modelling and evaluation of the multi-channel stereo reference listening room of the Hungarian National Radio. Authors: Éva Arató Borsi, Andor T. Fürjes (paper, presentation)

1998

'New Reference Listening Room for Two-Channel and Multichannel Stereo' Presented at AES'98
about the design of a reference listening room in the Hungarian National Radio. Authors: Éva Arató Borsi, Andor T. Fürjes (paper, presentation)

'Room Acoustics Evaluation of Small Rooms' Presented at ICA'98,
about finding parameters to evaluate room acoustic qualities in small rooms. Authors: Éva Arató Borsi, Andor T. Fürjes (paper, presentation)

Project reports & appereances

2022

'Sound system design - A theoretical and practical overview'
Basic overview of the topic including important terms, equations, tables, original illustrations prepared for the Engineering Chamber of Hungary, available to members for free (to prepare for exam)

2020

Tales of more than One Thousand and One Measurements (STI vs. room acoustic parameters -a study on extensive measurement data (2020)

The paper is a proof why STI should not be part of a room acoustic specification.

'Room acoustic engineering in common situations - Examples'
Examplar of room aoustic engineering cases including important terms, equations, tables, original illustrations prepared for the Engineering Chamber of Hungary, available to members for free (to prepare for exam)

2019

'Room acoustic engineering in common situations - Theory'
Basic overview of the topic including important terms, equations, tables, original illustrations prepared for the Engineering Chamber of Hungary, available to members for free (to prepare for exam)

Call for Adaptive Automotive Acoustic Emission Control - presentation (2016)

A presentation for a kick off meeting on how acoustic modelling, inverse modelling can be important for the new automotive technologies.

2006

'Festival Theatre Brings Meyer Sound Surround to Budapest'
About the loudspeaker system of the Festival Theatre Hall of the Palace of Arts of Budapest. (direct link to Meyer Sound news)

'Port of Entry' The Changi (Singapore) Airport had a huge new Terminal opened in 2006,
where the public space PA system is based on Duran Audio Intellivox system. There had been different configurations to consider and our work was to give an evaluation and support for the installation. Published in Pro Audio Asia, by Richard Lawn (articla)

2005

'Basement Jacks' The club named 'Süss fel nap' did invest both in audio systems and room acoustics (our work) to get the best out of the site. Published in Installation Europe, by Dan Goldstein