title: Modular feed-forward active noise control units for ventilation ducts.
abstract: This paper presents theoretical and experimental work on feed-forward active noise control for a ventilation duct. In particular three single channel control arrangements are investigated: (a) A classical widespread-mid-span configuration, where the control loudspeakers are located approximately half way through the duct and the reference and error microphones are placed close to inlet and outlet duct sections, respectively; (b) a compact-mid-span configuration, where both the reference and error microphones are moved close to the control loudspeakers to form a self-contained control unit, and (c) a compact-outlet configuration where the self-contained control unit is moved to the duct outlet. The two compact configurations offer self-evident practical installation and operation advantages. Moreover, the paper shows that they are characterized by much simpler control filters, which can be effectively implemented on modern audio digital signal processing boards and produce similar control performance to the classical widespread configuration.
authors.affiliation: Università degli Studi di Udine, Dipartimento di Ingegneria Elettrica Gestionale e Meccanica (DIEGM), Via delle Scienze, 208 33100, Udine, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Gardonio
authors.affiliation: Università degli Studi di Udine, Dipartimento di Ingegneria Elettrica Gestionale e Meccanica (DIEGM), Via delle Scienze, 208 33100, Udine, Italy.
authors.forename: J
authors.initials: J
authors.lastname: Rohlfing