Complete response function and system parameters for a loudspeaker with passive radiator

The response function, including all losses, for loudspeaker systems that use a passive radiator or a closed box is derived. It is shown that preferred system alignments, such as maximally flat ones, can be obtained while including both driver losses and internal enclosure losses that arise from the use of acoustic filling. A methodology for deriving the appropriate design curves is presented with an example. The process for obtaining system design parameters is explained, and it is shown how the properties of the filling material impact the design parameters. The additive effect of passive-radiator losses is presented, and a design method that compensates for these losses is outlined, including curves that provide the necessary correction factors for a particular case. The impact of leakage losses and a method of measuring them are also presented. Lastly, a method for accurately determining the parameters fp, and δ for an unknown passive radiator is presented in an appendix.