Driver Study

The force factor (BL), the mass (weight) of moving parts, the cone's stiffness, and the suspension system's compliance all shape how a speaker sounds. An obvious requirement, such as high sensitivity, deep bass, or low distortion… will give the direction for driver design or the modifications to fine-tune. Driver designers first arrange the key parameters and later balance them with others to produce qualified speakers.


They are building the simulation model to predict the frequency response in specific driving voltage and distance. The impedance curve tells the driver's low-frequency performance and how much inductance of the coil might impact high frequencies.


If problems cause a glitch or peak and dip in the frequency response, we can analyze the modes on the issued frequency and then implement solutions to fix or damp it.

An animation (.GIF) illustrates the diaphragm modes on the problematic frequencies.


The asymmetry of the suspension system, which includes the driver’s surround and spider, will increase Total Harmonic Distortion (THD), especially in low frequencies.


The plot of stiffness (Kms) versus displacement indicates the symmetry or asymmetry of suspension when the diaphragm moves front and back. The considerations for keeping the symmetry of both Kms (or Cms) and BL versus displacements are the most important ways to achieve low distortion. Adjusting one parameter usually influences another or even others; the simulated results can directly let the designer realize which ingredient should be fine-tuned.