Tools and facilities necessary to design world class drivers
Optimizing force factor and linearityIn a dynamic transducer the motor consists of a magnet system and a moving coil.
Ole Wolff designs single magnet motors as well as dual magnet motors (push-pull principle) depending on the individual performance and size target set by either the customer or Ole Wolff.
COMSOL Multiphysics® is used to optimize the magnetic motor system.
Force factor is measured using a Klippel test system. The plot shows BL(x) for a Ole Wolff headphone driver.
Advanced simulation tools such as COMSOL Multiphysics® are used in the development and optimization processes, taking nonlinear parameters and material properties into account.
In a dynamic transducer the voice coil is moving and therefore the mechanical properties have to be taken into account as well since the mass and dimension of the voice coil will affect the the acoustic performance.
Getting the design of the diaphram just right can seriously improve the speaker’s linearity and frequency performance.
Designing diaphragms has during the years been based on “cut & try” engineering.
This method is very time- and cost ineffective and even if huge resources are invested, there is no guarantee that the optimal design and performance has been reached. At Ole Wolff we have a faster and more reliable way of designing and optimizing diaphragms.
COMSOL Multiphysics® allow us to design diaphragms for various sizes of transducers where parameters such as foil type (single or multi layers), thicknesses of the foils, geometry of suspension, piston area and shape, number of stabilizing grooves in the diaphragm surface etc. can be simulated and performance verified before any mechanical tooling process is entered. This combined with years of experience assures shortest lead time and closest match to performance targets.
COMSOL Multiphysics® is used to optimize linearity of the compliance and break-up modes. Image shows motion analysis performed on a diaphragm for a 50mm receiver.