59617.8.5.5 Passive versus Active Crossovers.................................................... 625
17.8.6 Acoustic Boundaries.................................................................. 625
17.8.7 Conclusion......................................................................... 627
17.9 Characterization of Loudspeaker Performance................................................ 627
17.9.1 Motivation.......................................................................... 627
17.9.2 Efficiency and Sensitivity.............................................................. 627
17.9.3 Network Transfer Function............................................................. 628
17.9.4 Loudspeaker Transfer Function......................................................... 628
17.9.5 Impedance.......................................................................... 629
17.9.6 Distortion.......................................................................... 629
17.9.7 Characterization for Design Purposes..................................................... 631
17.9.8 Characterization for the User........................................................... 631
17.10 Direct Radiation of Sound............................................................... 632
17.10.1 Acoustics of Radiators............................................................... 633
17.10.1.1 Piston in an Infinite Baffle........................................................ 633
17.10.1.2 Piston Directivity............................................................... 634
17.10.2 Direct Radiator Enclosure Design...................................................... 635
17.10.2.1 Sealed-Box Systems............................................................. 635
17.10.2.2 Vented Boxes.................................................................. 636
17.10.2.3 Measurement of Thiele-Small Parameters............................................ 637
17.10.3 Horns............................................................................. 638
17.11 Loudspeaker Testing and Measurement..................................................... 638
17.11.1 Linear Transfer Function............................................................. 638
17.11.1.1 Spectrum Analysis Concepts....................................................... 638
17.11.2 Chart Recorders.................................................................... 639
17.11.3 Real Time Analyzers................................................................. 639
17.11.4 Time-Windowed Measurements........................................................ 639
17.11.4.1 Measurement of the Impulse Response............................................... 640
17.11.4.2 Maximum Length Sequence Measurements........................................... 640
17.11.4.3 Other FFT-Based Measurements................................................... 640
17.11.5 Swept Sine Measurements............................................................ 641
Reference.................................................................................. 641
Bibliography............................................................................... 641