Senior Electroacoustic Transducer Engineer

Summary We are a Swiss acoustics company developing an active noise reduction systems. We require a senior transducer engineer to own the electromechanical build of an electromechanical system: turn our requirements into a driver/diaphragm/suspension specification, procure and assemble prototypes, characterise them rigorously, and validate the measured behaviour against our lumped-parameter model predictions. This is hands-on, senior-level work. We have already performed limited analysis of the physics of a candidate exciter; we need someone who can challenge that selection where warranted, execute the build cleanly, and produce measurement data of publishable quality. This is not a role for generalists or early-career engineers — please do not apply without demonstrable transducer-specific experience. Scope of work Review our requirements note (motor, suspension, diaphragm; targets for force, Bl, Re, stiffness, moving mass, modal behaviour) and either confirm the candidate driver or propose justified alternatives, including OEM/semi-custom routes. Specify and source the diaphragm (stiff sandwich panel, ~100 × 120 mm), edge suspension (airtight, low-stiffness), and driver mounting hardware; design the bonded/clamped joints. Assemble two to three prototype units into the enclosure we supply. Characterise: full Thiele–Small / lumped-parameter identification per unit (Bl, Re, Le, Mms, Cms/Kms, Rms), suspension stiffness and unit-to-unit spread, diaphragm modal behaviour (first bending and rocking modes), air-leakage check of the sealed cavity. Validate against our model: measured mechanical impedance and (with our electronics) acoustic impedance/absorption in a duct per ISO 10534-2 two-microphone practice, with a written comparison of measured vs predicted parameters and a discrepancy analysis. Required skills and experience — the core of this role 5+ years designing electrodynamic transducers (loudspeaker drivers, exciters, voice-coil actuators) with shipped or published designs you can show. Fluency in lumped-parameter electroacoustic modelling — you think natively in Bl, Mms, Cms, Rms and can sanity-check a stiffness budget on paper. Hands-on measurement competence: Klippel (LSI/SIM or equivalent), impedance-based parameter identification, added-mass methods, laser vibrometry desirable. Suspension and surround engineering: spiders, half-roll surrounds, and airtight edge terminations; understanding of stiffness linearity, creep and ageing. Diaphragm structural know-how: sandwich/composite panels, bending-mode placement, bonded hard points. Prototype craftsmanship: precision adhesive assembly, coil–gap concentricity, small-batch build discipline with documented process. Impedance-tube or duct acoustic measurement experience (ISO 10534-2). Strong plus: experience with actively controlled or motional-feedback transducers, current-drive amplification, or servo woofers — this diaphragm is a control plant, not a loudspeaker, and the specification is controls-driven (parameter accuracy and repeatability matter more than SPL). Strong plus: an established vendor network for coils, magnets, surrounds and machined parts in EU or Asia. Engagement Part-time contract, approximately 10–15 hours/week for an initial 3 months, milestone-based (specification review → sourcing → assembled prototypes → characterisation report → validation report). Remote, with prototype hardware shipped both ways; EU/CH time-zone overlap preferred but not essential. NDA required before the requirements note is shared. Extension into a small-batch sample build is likely for the right person. To apply: Please include: (1) two or three transducer projects you personally engineered, with your specific role; (2) a sample characterisation report or parameter dataset you produced (redacted is fine); (3) your Klippel or equivalent measurement access; (4) your view, in a few sentences, on what dominates unit-to-unit Cms spread in low-cost exciters and how you would control it. Applications without these will not be reviewed.