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Transducer Parameters

Transducer Parameters

Small signal lumped parameters

  • Resonance frequency fs Mechanical quality factor Qms Electrical quality factor Qes DC resistance Re Force factor Bl(x=0) Mechanical resistance Rms(v=0) Stiffness Kms(x=0) and compliance Cms(x=0) Additional Thiele-Small parameters (e.g. Vas) Visco-elastic parameter (creep factor λ) Lossy inductance parameters (Wright, Leach, LR2 model)

Transducer nonlinearities (curve shape)

  • Force factor Bl(x) versus displacement x Mechanical compliance Cms(x) versus displacement x Mechanical stiffness Kms(x) versus displacement x Incremental stiffness Kinc(x) versus displacement x Inductance L(x,i) versus displacement x and current i Mechanical resistance Rms(v) versus velocity v Force-deflection curve F(x)

Single-valued nonlinear parameters

  • Voice coil offset Xoffset Suspension asymmetry Ak Maximal peak displacement Xmax Force factor limited peak displacement Xbi Suspension limited peak displacement Xc Inductance limited peak displacement XL Stiffness Kms(x=0) at the voice rest position Force factor Bl(x=0) at the voice coil rest position Effective stiffness related to effective resonance frequency Symmetry point xsym in force factor curve

Electrical impedance

  • Amplitude and phase response Nominal electrical impedance Zn Impedance measured by using a large signal model

Parameters of the enclosure

  • Port resonance fb Quality factor Qlb of vented enclosure