The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform

Sota Hiramatsu - One of the best experts on this subject based on the ideXlab platform.

  • EUSIPCO - MTF-based method of blind estimation of Reverberation Time in room acoustics
    2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). It is used to estimate the Reverberation Time from the reverberant signal without measuring room impulse response. We incorporated a process for estimating a parameter related to the Reverberation Time into the method of MTF-based speech deReverberation we previously proposed. We investigated whether the estimation process we then presented worked as a blind method of estimation and found problems with it. We therefore propose a new method of blindly estimating the Reverberation Time to resolve these problems, where the Reverberation Time is correctly estimated by inverse-MTF filtering in the modulation frequency domain. We evaluated the new method with the previous approach using both artificial MTF-based signals and speech signals to demonstrate how accurately it could estimate the Reverberation Time in artificial reverberant environments. The results revealed that it could accurately estimate Reverberation Times from observed reverberant signals. We also evaluated the new technique in real reverberant environments. The results suggested that it could accurately estimate the Reverberation Time from observed reverberant speech.

  • Blind estimation method of Reverberation Time based on concept of modulation transfer function
    Journal of the Acoustical Society of America, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method for blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). This method estimates the Reverberation Time from the reverberant signal without measuring room acoustics. In the MTF‐based speech deReverberation method, proposed by the authors, a process for estimating a parameter related to the Reverberation Time was incorporated. In this paper, we investigate whether the estimation process, previously presented by authors, works as a blind estimation method and point out a problem with their method. We then propose a new method for blindly estimating the Reverberation Time to resolve the problem. In the proposed method, the Reverberation Time is correctly estimated by inverse‐MTF filtering in the modulation frequency domain. We evaluated the proposed method with their method using both artificial MTF‐based signals and speech signals to show how well the proposed method correctly estimates the Reverberation Time in artificial rever...

  • MTF-based method of blind estimation of Reverberation Time in room acoustics
    European Signal Processing Conference, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time\nbased on the concept of the modulation transfer function (MTF). It is used\nto estimate the Reverberation Time from the reverberant signal without\nmeasuring room acoustics. We incorporated a process for estimating a\nparameter related to the Reverberation Time into the method of MTF-based\nspeech deReverberation we previously proposed. We investigated whether the\nestimation process we then presented worked as a blind method of estimation\nand found problems with it. We therefore propose a new method of blindly\nestimating the Reverberation Time to resolve these problems, where the\nReverberation Time is correctly estimated by inverse-MTF filtering in the\nmodulation frequency domain. We evaluated the new method with the previous\napproach using both artificial MTF-based signals and speech signals to\ndemonstrate how accurately it could estimate the Reverberation Time in\nartificial reverberant environments. The results revealed that it could\naccurately estimate Reverberation Times from observed reverberant signals.\nWe also evaluated the new technique in real reverberant environments. The\nresults suggested that it could accurately estimate the Reverberation Time\nfrom observed reverberant speech.

  • MTF-based method of blind estimation of Reverberation Time in room acoustics
    2008 16th European Signal Processing Conference, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). It is used to estimate the Reverberation Time from the reverberant signal without measuring room impulse response. We incorporated a process for estimating a parameter related to the Reverberation Time into the method of MTF-based speech deReverberation we previously proposed. We investigated whether the estimation process we then presented worked as a blind method of estimation and found problems with it. We therefore propose a new method of blindly estimating the Reverberation Time to resolve these problems, where the Reverberation Time is correctly estimated by inverse-MTF filtering in the modulation frequency domain. We evaluated the new method with the previous approach using both artificial MTF-based signals and speech signals to demonstrate how accurately it could estimate the Reverberation Time in artificial reverberant environments. The results revealed that it could accurately estimate Reverberation Times from observed reverberant signals. We also evaluated the new technique in real reverberant environments. The results suggested that it could accurately estimate the Reverberation Time from observed reverberant speech.

Masashi Unoki - One of the best experts on this subject based on the ideXlab platform.

  • EUSIPCO - MTF-based method of blind estimation of Reverberation Time in room acoustics
    2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). It is used to estimate the Reverberation Time from the reverberant signal without measuring room impulse response. We incorporated a process for estimating a parameter related to the Reverberation Time into the method of MTF-based speech deReverberation we previously proposed. We investigated whether the estimation process we then presented worked as a blind method of estimation and found problems with it. We therefore propose a new method of blindly estimating the Reverberation Time to resolve these problems, where the Reverberation Time is correctly estimated by inverse-MTF filtering in the modulation frequency domain. We evaluated the new method with the previous approach using both artificial MTF-based signals and speech signals to demonstrate how accurately it could estimate the Reverberation Time in artificial reverberant environments. The results revealed that it could accurately estimate Reverberation Times from observed reverberant signals. We also evaluated the new technique in real reverberant environments. The results suggested that it could accurately estimate the Reverberation Time from observed reverberant speech.

  • Blind estimation method of Reverberation Time based on concept of modulation transfer function
    Journal of the Acoustical Society of America, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method for blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). This method estimates the Reverberation Time from the reverberant signal without measuring room acoustics. In the MTF‐based speech deReverberation method, proposed by the authors, a process for estimating a parameter related to the Reverberation Time was incorporated. In this paper, we investigate whether the estimation process, previously presented by authors, works as a blind estimation method and point out a problem with their method. We then propose a new method for blindly estimating the Reverberation Time to resolve the problem. In the proposed method, the Reverberation Time is correctly estimated by inverse‐MTF filtering in the modulation frequency domain. We evaluated the proposed method with their method using both artificial MTF‐based signals and speech signals to show how well the proposed method correctly estimates the Reverberation Time in artificial rever...

  • Blind estimation method of Reverberation Time based on concept of modulation transfer function
    Proc. Intl. Conf. on Acoustics, 2008
    Co-Authors: Masashi Unoki, Sadaharu Hiramatsu
    Abstract:

    This paper proposes a method for blindly estimating the Reverberation Time based on the concept of the modulation transfer function ({MTF}). This method estimates the Reverberation Time from the reverberant signal without measuring room acoustics. In the {MTF}-based speech deReverberation method, proposed by the authors, a process for estimating a parameter related to the Reverberation Time was incorporated. In this paper, we investigate whether the estimation process, previously presented by authors, works as a blind estimation method and point out a problem with their method. We then propose a new method for blindly estimating the Reverberation Time to resolve the problem. In the proposed method, the Reverberation Time is correctly estimated by inverse-{MTF} filtering in the modulation frequency domain. We evaluated the proposed method with their method using both artificial {MTF}-based signals and speech signals to show how well the proposed method correctly estimates the Reverberation Time in artificial reverberant environments. Results suggested that the proposed method correctly estimates Reverberation Times from the observed reverberant signals.

  • MTF-based method of blind estimation of Reverberation Time in room acoustics
    European Signal Processing Conference, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time\nbased on the concept of the modulation transfer function (MTF). It is used\nto estimate the Reverberation Time from the reverberant signal without\nmeasuring room acoustics. We incorporated a process for estimating a\nparameter related to the Reverberation Time into the method of MTF-based\nspeech deReverberation we previously proposed. We investigated whether the\nestimation process we then presented worked as a blind method of estimation\nand found problems with it. We therefore propose a new method of blindly\nestimating the Reverberation Time to resolve these problems, where the\nReverberation Time is correctly estimated by inverse-MTF filtering in the\nmodulation frequency domain. We evaluated the new method with the previous\napproach using both artificial MTF-based signals and speech signals to\ndemonstrate how accurately it could estimate the Reverberation Time in\nartificial reverberant environments. The results revealed that it could\naccurately estimate Reverberation Times from observed reverberant signals.\nWe also evaluated the new technique in real reverberant environments. The\nresults suggested that it could accurately estimate the Reverberation Time\nfrom observed reverberant speech.

  • MTF-based method of blind estimation of Reverberation Time in room acoustics
    2008 16th European Signal Processing Conference, 2008
    Co-Authors: Masashi Unoki, Sota Hiramatsu
    Abstract:

    This paper proposes a method of blindly estimating the Reverberation Time based on the concept of the modulation transfer function (MTF). It is used to estimate the Reverberation Time from the reverberant signal without measuring room impulse response. We incorporated a process for estimating a parameter related to the Reverberation Time into the method of MTF-based speech deReverberation we previously proposed. We investigated whether the estimation process we then presented worked as a blind method of estimation and found problems with it. We therefore propose a new method of blindly estimating the Reverberation Time to resolve these problems, where the Reverberation Time is correctly estimated by inverse-MTF filtering in the modulation frequency domain. We evaluated the new method with the previous approach using both artificial MTF-based signals and speech signals to demonstrate how accurately it could estimate the Reverberation Time in artificial reverberant environments. The results revealed that it could accurately estimate Reverberation Times from observed reverberant signals. We also evaluated the new technique in real reverberant environments. The results suggested that it could accurately estimate the Reverberation Time from observed reverberant speech.

Raf Orlowski - One of the best experts on this subject based on the ideXlab platform.

  • Balancing Sound Strength and Reverberation Time in Small Concert Halls by Means of Variable Acoustics
    Noise & Vibration Worldwide, 2010
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It has been measured in six small concert halls in Cambridge, UK, in combination with measurements of Reverberation Time. The aim is to investigate the relationship between sound strength and Reverberation Time in small halls and to study the effect of variable acoustics in these halls. Large ensembles in small halls are often too loud and it is desirable to reduce the sound level. This can be done by introducing acoustically absorbent material but the Reverberation Time is also decreased. Reverberation Time cannot be decreased by an arbitrary amount as it is closely related to sound quality. Therefore, Reverberation Time and strength have to be carefully balanced in order to maintain sufficient reverberance whilst at the same Time avoiding excessive loudness. The study also compares measured strength levels with values derived from traditional and revised theories fo...

  • sound strength and Reverberation Time in small concert halls
    Applied Acoustics, 2009
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Abstract Sound strength and Reverberation Time measurements have been carried out in six small concert halls in Cambridge, UK. The sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It compares integrated impulse responses at a point in the measured room with that measured at ten metres distance in the free field. The aim of the measurements is to investigate the acoustic characteristics of the halls concerning sound strength and Reverberation Time. Furthermore the effect of the variable acoustics in the halls on these parameters is discussed in this paper. Especially for bigger ensembles it is often desirable to reduce the sound level in a small concert hall. The measurement results show that for a fixed hall volume, this can primarily be achieved by decreasing the Reverberation Time in the hall. However, with regard to the sound quality of a hall and the recommended Reverberation Times for chamber music, Reverberation Time cannot be reduced by an arbitrary extent. Therefore Reverberation Time and strength have to be balanced very carefully in order to obtain sufficient Reverberation whilst at the same Time avoiding excessive loudness. Finally the measured strength levels are compared to values derived from traditional and revised theory [Barron M, Lee L-J. Energy relations in concert auditoriums. J Acoust Soc Am 1988;84(2):618–28] on strength calculations in order to assess the accuracy of the theory for small chamber music halls. Possible reasons for the low measured strength levels observed are discussed with reference to related design features and objective acoustic parameters.

  • Sound strength and Reverberation Time in small concert halls
    Applied Acoustics, 2009
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Sound strength and Reverberation Time measurements have been carried out in six small concert halls in Cambridge, UK. The sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It compares integrated impulse responses at a point in the measured room with that measured at ten metres distance in the free field. The aim of the measurements is to investigate the acoustic characteristics of the halls concerning sound strength and Reverberation Time. Furthermore the effect of the variable acoustics in the halls on these parameters is discussed in this paper. Especially for bigger ensembles it is often desirable to reduce the sound level in a small concert hall. The measurement results show that for a fixed hall volume, this can primarily be achieved by decreasing the Reverberation Time in the hall. However, with regard to the sound quality of a hall and the recommended Reverberation Times for chamber music, Reverberation Time cannot be reduced by an arbitrary extent. Therefore Reverberation Time and strength have to be balanced very carefully in order to obtain sufficient Reverberation whilst at the same Time avoiding excessive loudness. Finally the measured strength levels are compared to values derived from traditional and revised theory [Barron M, Lee L-J. Energy relations in concert auditoriums. J Acoust Soc Am 1988;84(2):618-28] on strength calculations in order to assess the accuracy of the theory for small chamber music halls. Possible reasons for the low measured strength levels observed are discussed with reference to related design features and objective acoustic parameters. © 2009 Elsevier Ltd. All rights reserved.

Marc Aretz - One of the best experts on this subject based on the ideXlab platform.

  • Balancing Sound Strength and Reverberation Time in Small Concert Halls by Means of Variable Acoustics
    Noise & Vibration Worldwide, 2010
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It has been measured in six small concert halls in Cambridge, UK, in combination with measurements of Reverberation Time. The aim is to investigate the relationship between sound strength and Reverberation Time in small halls and to study the effect of variable acoustics in these halls. Large ensembles in small halls are often too loud and it is desirable to reduce the sound level. This can be done by introducing acoustically absorbent material but the Reverberation Time is also decreased. Reverberation Time cannot be decreased by an arbitrary amount as it is closely related to sound quality. Therefore, Reverberation Time and strength have to be carefully balanced in order to maintain sufficient reverberance whilst at the same Time avoiding excessive loudness. The study also compares measured strength levels with values derived from traditional and revised theories fo...

  • sound strength and Reverberation Time in small concert halls
    Applied Acoustics, 2009
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Abstract Sound strength and Reverberation Time measurements have been carried out in six small concert halls in Cambridge, UK. The sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It compares integrated impulse responses at a point in the measured room with that measured at ten metres distance in the free field. The aim of the measurements is to investigate the acoustic characteristics of the halls concerning sound strength and Reverberation Time. Furthermore the effect of the variable acoustics in the halls on these parameters is discussed in this paper. Especially for bigger ensembles it is often desirable to reduce the sound level in a small concert hall. The measurement results show that for a fixed hall volume, this can primarily be achieved by decreasing the Reverberation Time in the hall. However, with regard to the sound quality of a hall and the recommended Reverberation Times for chamber music, Reverberation Time cannot be reduced by an arbitrary extent. Therefore Reverberation Time and strength have to be balanced very carefully in order to obtain sufficient Reverberation whilst at the same Time avoiding excessive loudness. Finally the measured strength levels are compared to values derived from traditional and revised theory [Barron M, Lee L-J. Energy relations in concert auditoriums. J Acoust Soc Am 1988;84(2):618–28] on strength calculations in order to assess the accuracy of the theory for small chamber music halls. Possible reasons for the low measured strength levels observed are discussed with reference to related design features and objective acoustic parameters.

  • Sound strength and Reverberation Time in small concert halls
    Applied Acoustics, 2009
    Co-Authors: Marc Aretz, Raf Orlowski
    Abstract:

    Sound strength and Reverberation Time measurements have been carried out in six small concert halls in Cambridge, UK. The sound strength G is a measure of the physical sound level in a concert hall and is closely related to the subjective sensation of loudness. It compares integrated impulse responses at a point in the measured room with that measured at ten metres distance in the free field. The aim of the measurements is to investigate the acoustic characteristics of the halls concerning sound strength and Reverberation Time. Furthermore the effect of the variable acoustics in the halls on these parameters is discussed in this paper. Especially for bigger ensembles it is often desirable to reduce the sound level in a small concert hall. The measurement results show that for a fixed hall volume, this can primarily be achieved by decreasing the Reverberation Time in the hall. However, with regard to the sound quality of a hall and the recommended Reverberation Times for chamber music, Reverberation Time cannot be reduced by an arbitrary extent. Therefore Reverberation Time and strength have to be balanced very carefully in order to obtain sufficient Reverberation whilst at the same Time avoiding excessive loudness. Finally the measured strength levels are compared to values derived from traditional and revised theory [Barron M, Lee L-J. Energy relations in concert auditoriums. J Acoust Soc Am 1988;84(2):618-28] on strength calculations in order to assess the accuracy of the theory for small chamber music halls. Possible reasons for the low measured strength levels observed are discussed with reference to related design features and objective acoustic parameters. © 2009 Elsevier Ltd. All rights reserved.

Fergus R. Fricke - One of the best experts on this subject based on the ideXlab platform.

  • The Prediction of Reverberation Time Using Optimal Neural Networks
    Building Acoustics, 2002
    Co-Authors: Joseph Nannariello, Fergus R. Fricke
    Abstract:

    A neural network approach to predicting the Reverberation Time, RT60, at the conceptual design stage of auditoria, and churches is presented. The results of investigations previously carried out indicated that there was a good basis for using trained neural networks to predict the Reverberation Time for unoccupied enclosures but that 15 input variables were required to achieve the desired accuracy. As the number of input variables that can be readily identified and quantified at the early design stage is small, the objective of this work is to reduce network size and to obtain optimal neural networks. The results showed that the generalization performance of neural networks with simplified internal representation is efficient. Generally, the Reverberation Time prediction accuracy of the network models, for the six enclosures 'tested', is within the range of the subjective difference limen (ΔT/T 5%).

  • The prediction of Reverberation Time using neural network analysis
    Applied Acoustics, 1999
    Co-Authors: Joseph Nannariello, Fergus R. Fricke
    Abstract:

    Abstract An alternative method of predicting the Reverberation Time for enclosures, using artificial neural networks, has been investigated. The study begins with the hypothesis that, at the conceptual design stage, Reverberation Time predictions are too difficult to derive using existing computer models, and too inaccurate when using other methods and that a more explicit and quicker method of predicting Reverberation Time is required. Assessments are made of the predictive powers of trained neural networks by comparing the predicted Reverberation Times obtained using neural networks with those using Sabine's and Eyring's ‘classical equations’ and the ray tracing model ODEON 2.6D. The results indicate that there is a good basis for using trained neural networks to predict the Reverberation Time for enclosures but that 15 input variables are required to achieve accuracy of ±10%. In addition, the results show that neural network analysis can identify those variables which have the greatest effect on the predicted Reverberation Times.

  • Reverberation Time predictions using neural network analysis
    Journal of the Acoustical Society of America, 1998
    Co-Authors: Joseph Nannariello, Fergus R. Fricke
    Abstract:

    The study aims to utilize neural network analysis to develop a method to predict the Reverberation Time for enclosures—in the low and mid frequencies—by using neural networks that have been trained with constructional and acoustical data. The study begins with the hypothesis that, in practice, Reverberation Time predictions are too difficult to undertake using existing computer models, and too inaccurate when using other methods. Specifically, the study aims at providing an expeditious and accurate method of predicting the Reverberation Time of enclosures at the initial design stage. To substantiate the hypothesis, and to bring into effect the aims of the study, assessments are made of the predictive powers of the trained neural networks. The results of the investigations have indicated that there is a good basis for using trained neural networks to predict the Reverberation Time for enclosures. The results have also shown that neural network analysis can identify those variables that have an effect on the predicted Reverberation Times.