Sound Producing Devices TRIZ Cases

A guided stair machine uses a polyurethane track strip for noise damping and remote speed sequences for hands-free workouts.

Selects coherent vibration signals across noise bands for more effective vehicle noise reduction.

Calculate and display speaker or microphone placement for target sound pressure.

A feedback controller uses actual out-of-vehicle noise to drive a sound player that counteracts AVAS noise in the cabin.

The device detects launch-control preparation and shifts sound frequencies to signal acceleration through simulated engine audio.

Early reflections use real-world geometry while late reverberations use virtual geometry for immersive, boundary-aware spatial audio.

Virtual reflection surfaces reduce processing load for real-time VR stereophonic sound.

A light sensor and electromagnet move a resonator member to adjust acoustic resonance and frequency as ambient light changes.

Hollow rectangular columns and air cavities create impedance mismatch for 20 dB average underwater sound reduction at low frequencies.

A reference microphone and virtual error signal drive beam-forming speakers to cancel fan noise without compromising thermal management.

This case combines multiple error microphones and one adaptive filter, matching gain and delay to handle transfer-function differences.