Digital Equalization

In the last decade several efforts have been made in the field of acoustic equalization which brought to a variety of different scenarios and different approaches. In most cases the equalization purpose is to provide a fixed frequency curve in order to modify the listening experience. It could be referred to the listening of particular musical genres or sometimes to have low frequencies boosted in the presence of background noise (e.g automotive equalization). In particular, the automobile is a well-known small noisy environment with several negative influences on the spectral, spatial and temporal attributes of the reproduced sound field. Specifically, depending on the absorbing or reflecting interior materials, on the position of the loudspeakers and on the shape of the car cabin, the reflected sounds can attenuate or amplify the direct sound from the loudspeakers. In this context, audio equalization is strongly required to enhance tone quality and modify frequency response to approximately obtain desired results in terms of audio quality. Equalizers are used to compensate for speaker placement, environment characteristics and to enhance the listening experience in relation to the user requirements. This compensation is accomplished by cutting or boosting, i. e.attenuating or amplifying a range of frequencies.

The main topics are:

  • Room/Car Fixed Equalization
  • Room/Car Adaptive Equalization
  • Single point and Multi point equalization
  • Multichannel equalization

Related projects:

Related pubblications:

  1. S Cecchi, P Peretti, L Palestini, F Piazza, F Bettarelli and A Lattanzi. Real Time implementation of an Innovative Digital Audio Equalizer. In Proc. 123rd Audio Engineering Society Convention. 2007. BibTeX

    @inproceedings{cecchi-aes-07,
	author = "Cecchi, S. and Peretti, P. and Palestini, L. and Piazza, F. and Bettarelli, F. and Lattanzi, A.",
	title = "{Real Time implementation of an Innovative Digital Audio Equalizer}",
	booktitle = "Proc. 123rd Audio Engineering Society Convention",
	year = 2007,
	month = "Oct.",
	address = "New York, NY, USA"
}

  2. S Cecchi, L Palestini, E Moretti and F Piazza. A New Approach to Digital Audio Equalization. In Proc. Workshop on Applications of Signal Processing to Audio and Acoustics. October 2007, 62-65. BibTeX

    @inproceedings{cecchi-waspaa-07,
	author = "Cecchi, S. and Palestini, L. and Moretti, E. and Piazza, F.",
	title = "{A New Approach to Digital Audio Equalization}",
	booktitle = "Proc. Workshop on Applications of Signal Processing to Audio and Acoustics",
	year = 2007,
	month = "October",
	address = "New Paltz, NY, USA",
	pages = "62-65"
}

  3. F Piazza, S Cecchi, L Palestini, P Peretti, F Bettarelli, A Lattanzi, E Moretti and E Ciavattini. Demonstrating hArtes Project Approach through an Advanced Car Information System. In Proc. International Symposium on Vehicular Computing Systems. 2008. BibTeX

    @inproceedings{piazza-isvcs-08,
	author = "Piazza, F. and Cecchi, S. and Palestini, L. and Peretti, P. and Bettarelli, F. and Lattanzi, A. and Moretti, E. and Ciavattini, E.",
	title = "{Demonstrating hArtes Project Approach through an Advanced Car Information System}",
	booktitle = "Proc. International Symposium on Vehicular Computing Systems",
	year = 2008,
	month = "Jul.",
	address = "Dublin, Ireland"
}

  4. S Cecchi, L Palestini, P Peretti, E Moretti, F Piazza, A Lattanzi and F Bettarelli. Advanced Audio Algorithms for a Real Automotive Digital Audio System. In Proc. 125th Audio Engineering Society Convention. 2008. BibTeX

    @inproceedings{cecchi-aes-08,
	author = "Cecchi, S. AND Palestini, L. AND Peretti, P. AND Moretti, E. AND Piazza, F. AND Lattanzi, A. AND Bettarelli, F.",
	title = "{Advanced Audio Algorithms for a Real Automotive Digital Audio System}",
	booktitle = "Proc. 125th Audio Engineering Society Convention",
	year = 2008,
	month = "Oct.",
	address = "New York, NY, USA"
}

  5. S Cecchi, L Palestini, P Peretti, F Piazza, F Bettarelli and R Toppi. Automotive Audio Equalization. In Proc. 36th Audio Engineering Society Conference. 2009. BibTeX

    @inproceedings{cecchi-aes-09,
	author = "Cecchi, S. and Palestini, L. and Peretti, P. and Piazza, F. and Bettarelli, F. and Toppi, R.",
	title = "{Automotive Audio Equalization}",
	booktitle = "Proc. 36th Audio Engineering Society Conference",
	year = 2009,
	month = "Jun.",
	address = "Deaborn, MI, USA"
}

  6. S Cecchi, L Palestini, P Peretti, F Piazza and A Carini. Multipoint Equalization of Digital Car Audio Systems. In Proc. 6th Int'l Symposium on Image and Signal Processing and Analysis. 2009, 650-655. BibTeX

    @inproceedings{cecchi-ispa-09,
	author = "Cecchi, S. and Palestini, L. and Peretti, P. and Piazza, F. and Carini, A.",
	title = "{Multipoint Equalization of Digital Car Audio Systems}",
	booktitle = "Proc. 6th Int'l Symposium on Image and Signal Processing and Analysis",
	year = 2009,
	month = "Sep.",
	address = "Salzburg, Austria",
	pages = "650-655"
}

  7. S Cecchi, L Palestini, P Peretti, L Romoli, F Piazza and A Carini. Evaluation of a Multipoint Equalization System based on Impulse Responses Prototype Extraction. In Proc. 127th Audio Engineering Society Convention. 2009. BibTeX

    @inproceedings{cecchi-aes2-09,
	author = "Cecchi, S. and Palestini, L. and Peretti, P. and Romoli, L. and Piazza, F. and Carini, A.",
	title = "{Evaluation of a Multipoint Equalization System based on Impulse Responses Prototype Extraction}",
	booktitle = "Proc. 127th Audio Engineering Society Convention",
	year = 2009,
	month = "Oct.",
	address = "New York, NY, USA"
}

  8. A Carini, S Cecchi and L Romoli. Multipoint Room Response Equalization with Group Delay Compensation. In Proc. Workshop on Acoustic Echo and Noise Control . 2010, . BibTeX

    @inproceedings{carini-iwaenc-10,
	title = "{Multipoint Room Response Equalization with Group Delay Compensation}",
	author = "Carini, A. and Cecchi, S. and Romoli, L.",
	booktitle = "Proc. Workshop on Acoustic Echo and Noise Control",
	volume = "",
	address = "Tel Aviv, Israel",
	month = "Sep.",
	year = 2010,
	pages = ""
}

  9. S Cecchi, A Primavera, F Piazza, F Bettarelli, E Ciavattini, R Toppi, J G F Coutinho, W Luk, C Pilato, F Ferrandi, V Sima and K Bertels. The hArtes CarLab: A New Approach to Advanced Algorithms Development for Automotive Audio. In Proc. 129th Audio Engineering Society Convention . 2010, . BibTeX

    @inproceedings{cecchi-aes-10b,
	title = "{The hArtes CarLab: A New Approach to Advanced Algorithms Development for Automotive Audio}",
	author = "Cecchi, S. and Primavera, A. and Piazza, F. and Bettarelli, F. and Ciavattini, E. and Toppi, R. and Coutinho, J. G. F. and Luk, W. and Pilato, C. and Ferrandi, F. and Sima, V. and Bertels, K.",
	booktitle = "Proc. 129th Audio Engineering Society Convention",
	volume = "",
	address = "San Francisco, CA, USA",
	month = "Oct.",
	year = 2010,
	pages = ""
}

  10. S Cecchi, L Palestini, P Peretti, L Romoli, F Piazza and A Carini. Evaluation of a Multipoint Equalization System based on Impulse Responses Prototype Extraction. J.~Audio Eng.~Soc. 59(3):110-123, 2011. BibTeX

    @article{cecchi-jaes-11,
	author = "Cecchi, S. and Palestini, L. and Peretti, P. and Romoli, L. and Piazza, F. and Carini, A.",
	title = "{Evaluation of a Multipoint Equalization System based on Impulse Responses Prototype Extraction}",
	journal = "J.~Audio Eng.~Soc.",
	volume = 59,
	number = 3,
	pages = "110-123",
	year = 2011,
	month = "Mar."
}

  11. S Cecchi, A Primavera, F Piazza and A Carini. An adaptive multiple position room response equalizer. In Proc. 18th European Signal Processing Conference . 2011, . BibTeX

    @inproceedings{cecchi-eusipco-11,
	title = "{An adaptive multiple position room response equalizer}",
	author = "Cecchi, S. and Primavera, A. and Piazza, F. and Carini, A.",
	booktitle = "Proc. 18th European Signal Processing Conference",
	volume = "",
	address = "Barcelona, Spain",
	month = "Aug.",
	year = 2011,
	pages = ""
}

  12. S Cecchi, L Romoli, F Piazza and A Carini. Multipoint Room Response Equalization with Group Delay Compensation: Subjective Listening Tests. In Proc. 7th Int'l Symposium on Image and Signal Processing and Analysis. 2011, . BibTeX

    @inproceedings{cecchi-ispa-11,
	author = "Cecchi, S. and Romoli, L. and Piazza, F. and Carini, A.",
	title = "{Multipoint Room Response Equalization with Group Delay Compensation: Subjective Listening Tests}",
	booktitle = "Proc. 7th Int'l Symposium on Image and Signal Processing and Analysis",
	year = 2011,
	month = "Sep.",
	address = "Dubrovnik, Croatia",
	pages = ""
}

  13. S Cecchi, F Piazza and A Carini. Subjective Evaluation of a Multiple Position Room Response Equalization Approach Applied in Frequency Domain. In Proc. 7th Int'l Symposium on Image and Signal Processing and Analysis. 2011, . BibTeX

    @inproceedings{cecchi-ispa2-11,
	author = "Cecchi, S. and Piazza, F. and Carini, A.",
	title = "{Subjective Evaluation of a Multiple Position Room Response Equalization Approach Applied in Frequency Domain}",
	booktitle = "Proc. 7th Int'l Symposium on Image and Signal Processing and Analysis",
	year = 2011,
	month = "Sep.",
	address = "Dubrovnik, Croatia",
	pages = ""
}

  14. A Carini, S Cecchi, I Omiciuolo, F Piazza and G L Sicuranza. Multiple Position Room Response Equalization in Frequency Domain. IEEE Trans.~Audio, Speech and Language Processing 20(1):122-135, 2012. BibTeX

    @article{carini-jasl-11,
	author = "Carini, A. and Cecchi, S. and Omiciuolo, I. and Piazza, F. and Sicuranza, G. L.",
	title = "{Multiple Position Room Response Equalization in Frequency Domain}",
	journal = "IEEE Trans.~Audio, Speech and Language Processing",
	volume = 20,
	number = 1,
	pages = "122-135",
	year = 2012,
	month = "Jan."
}

  15. A Primavera, S Cecchi, F Piazza and A Carini. Mixed Time-Frequency Approach for Multipoint Room Response Equalization. In Proc. 45th Audio Engineering Society Conference . 2012, . BibTeX

    @inproceedings{primavera-aes-12,
	title = "{Mixed Time-Frequency Approach for Multipoint Room Response Equalization}",
	author = "Primavera, A. and Cecchi, S. and Piazza, F. and Carini, A.",
	booktitle = "Proc. 45th Audio Engineering Society Conference",
	volume = "",
	address = "Helsinki, Finland",
	month = "Mar.",
	year = 2012,
	pages = ""
}

  16. S Cecchi, A Primavera, A Carini and F Piazza. An Adaptive Multiple Position Room Response Equalizer In Warped Domain. In European Signal Processing Conference . 2012, 1955-1959. BibTeX

    @inproceedings{cecchi-eusipco-12,
	title = "{An Adaptive Multiple Position Room Response Equalizer In Warped Domain}",
	author = "Cecchi, S. and Primavera, A. and Carini, A. and Piazza, F.",
	booktitle = "European Signal Processing Conference",
	volume = "",
	address = "Bucharest, Romania",
	month = "Aug.",
	year = 2012,
	pages = "1955-1959"
}

  17. S Cecchi, F Bettarelli and F Piazza. Multipoint Equalization for Car Audio Systems. In Proc. 48th Audio Engineering Society Conference . 2012, . BibTeX

    @inproceedings{cecchi-aes-12,
	title = "{Multipoint Equalization for Car Audio Systems}",
	author = "Cecchi, S. and Bettarelli, F. and Piazza, F.",
	booktitle = "Proc. 48th Audio Engineering Society Conference",
	volume = "",
	address = "Monaco, Germany",
	month = "Sep.",
	year = 2012,
	pages = ""
}

  18. M Virgulti, S Cecchi, A Primavera, L Romoli, E Ciavattini, F Bettarelli and F Piazza. Optimized Implementation of an Innovative Digital Audio Equalizer. In Proc. 133rd Audio Engineering Society Convention . 2012, . BibTeX

    @inproceedings{virgulti-aes-12,
	title = "{Optimized Implementation of an Innovative Digital Audio Equalizer}",
	author = "Virgulti, M. and Cecchi, S. and Primavera, A. and Romoli, L. and Ciavattini, E. and Bettarelli, F. and Piazza, F.",
	booktitle = "Proc. 133rd Audio Engineering Society Convention",
	volume = "",
	address = "San Francisco, CA, USA",
	month = "Oct.",
	year = 2012,
	pages = ""
}

  19. S Cecchi, M Virgulti, F Bettarelli, S Doria and F Piazza. Development of Multipoint Mixed-phase Equalization system for multiple environments. In Proc. 134th Audio Engineering Society Convention . May 2013, . BibTeX

    @inproceedings{cecchi-aes134-13,
	title = "{Development of Multipoint Mixed-phase Equalization system for multiple environments}",
	author = "Cecchi, S. and Virgulti, M. and Bettarelli, F. and Doria, S. and Piazza, F.",
	booktitle = "Proc. 134th Audio Engineering Society Convention",
	volume = "",
	address = "Rome, Italy",
	month = "May",
	year = 2013,
	pages = ""
}

  20. S Cecchi, L Romoli, F Piazza and A Carini. A Multichannel and Multiple Position Adaptive Room Response Equalizer in Warped Domain. In Proc. 8th Int'l Symposium on Image and Signal Processing and Analysis . 2013, . BibTeX

    @inproceedings{cecchi-ispa-13,
	title = "{A Multichannel and Multiple Position Adaptive Room Response Equalizer in Warped Domain}",
	author = "Cecchi, S. and Romoli, L. and Piazza, F. and Carini, A.",
	booktitle = "Proc. 8th Int'l Symposium on Image and Signal Processing and Analysis",
	volume = "",
	address = "Trieste, Italy",
	month = "Sep.",
	year = 2013,
	pages = ""
}

  21. M Virgulti, S Cecchi and F Piazza. IIR Filter Approximation of an Innovative Digital Audio Equalizer. In Proc. 8th Int'l Symposium on Image and Signal Processing and Analysis . 2013, . BibTeX

    @inproceedings{virgulti-ispa-13,
	title = "{IIR Filter Approximation of an Innovative Digital Audio Equalizer}",
	author = "Virgulti, M. and Cecchi, S. and Piazza, F.",
	booktitle = "Proc. 8th Int'l Symposium on Image and Signal Processing and Analysis",
	volume = "",
	address = "Trieste, Italy",
	month = "Sep.",
	year = 2013,
	pages = ""
}

  22. S Cecchi, L Romoli, F Piazza, B Bank and A Carini. A Novel Approach for Prototype Extraction in a Multipoint Equalization Procedure. In Proc. 136th Audio Engineering Society Convention . 2014, . BibTeX

    @inproceedings{cecchi-aes136-14,
	title = "{A Novel Approach for Prototype Extraction in a Multipoint Equalization Procedure}",
	author = "Cecchi, S. and Romoli, L. and Piazza, F. and Bank, B. and Carini, A.",
	booktitle = "Proc. 136th Audio Engineering Society Convention",
	volume = "",
	address = "Berlin, Germany",
	month = "Apr.",
	year = 2014,
	pages = ""
}

  23. S Cecchi, L Romoli, A Carini and F Piazza. A Multichannel and Multiple Position Adaptive Room Response Equalizer in Warped Domain: Real-time Implementation and Performance Evaluation. Applied Acoustics ():, 2014. BibTeX

    @article{cecchi-apac-14,
	author = "Cecchi, S. and Romoli, L. and Carini, A. and Piazza, F.",
	title = "{A Multichannel and Multiple Position Adaptive Room Response Equalizer in Warped Domain: Real-time Implementation and Performance Evaluation}",
	journal = "{Applied Acoustics}",
	volume = "",
	number = "",
	pages = "",
	year = 2014,
	month = ""
}

  24. S Cecchi, A Primavera, F Piazza, F Bettarelli and J Li. Advanced Audio Spatializer combined with a Multipoint Equalization System. In Proc. IEEE World congress on Computational Intelligence. July 2014, . BibTeX

    @inproceedings{cecchi-wcci-14,
	title = "{Advanced Audio Spatializer combined with a Multipoint Equalization System}",
	author = "Cecchi, S. and Primavera, A. and Piazza, F. and Bettarelli, F. and Li, J.",
	booktitle = "Proc. {IEEE} World congress on Computational Intelligence",
	address = "Beijing, China",
	year = 2014,
	month = "Jul",
	pages = "",
	notes = "accepted for presentation"
}