Automotive
Speakers for EVs and gas vehicles
Problems
Heavy, bulky, inefficient electrodynamic speakers
In a standard vehicle setup, there are more than ten speakers that collectively weigh over 20 pounds and occupy substantial space. Additionally, these conventional electrodynamic speakers exhibit inefficiency, with 90% of the consumed energy being converted into heat rather than sound. Furthermore, due to their bulky nature, these speakers need to be discreetly placed in various locations, including corners and doors of the vehicle, which are not ideal for optimal sound performance.
solution
Flat panel speakers
With its ultra-slim profile, as thin as 1mm, Dragonfly™ seamlessly attaches to the rear side of various interior panels, such as dashboard and ceiling panels to create piezo flat panel speakers. These speakers can be combined with an electrodynamic subwoofer to create a complete premium audio system. The key advantages include:
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Weight and Space Savings: Substituting conventional speakers with Dragonfly™ can result in up to 90% reduction in both weight and installation space.
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Enhanced Efficiency: 3x more efficient than electrodynamic speakers due to their superior energy conversion rate of the piezo material. This efficiency is particularly critical for electric vehicles (EVs).
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Improved Audio Quality: Can be installed closer to the listener’s ears, enhancing both efficiency and audio performance, especially in the high-frequency range.
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Interior Design Freedom: Dragonfly™ offers greater freedom in interior design, as it eliminates the need for grilles or openings.
Demo
Car center console touch screen
For demonstration purposes, a Dragonfly™ has been affixed to the rear side of a 12″ OLED touch display, creating a flat panel speaker with a thickness of approximately 3mm. The display is securely mounted on a wooden frame using double-sided tape along its perimeter, simulating the setup found in modern cars. Powering the Dragonfly™ is a class D amplifier from our DEV kit. The audio input for the demonstration is sourced from a laptop via a 3.5mm cable, while the recording was conducted using a smartphone. Furthermore, the sound pressure level (SPL) curve was meticulously measured using a UMIK-1 microphone and REW software.
Result
High fidelity sounds
The findings indicate that the piezo speaker successfully achieved sufficient loudness, despite the inherent challenges of a relatively small (12″), thick (3mm), and heavy (>2 lbs) touch screen display – characteristics that are contrary to an ideal sound radiator. The SPL curve illustrates a commendable frequency response ranging from approximately 130 Hz to 20 kHz. Notably, the lower frequency limit (130 Hz) can be tailored to meet specific requirements.
In summary, these results underscore the potential of the Dragonfly™ – with its full-range capability, slim form factor (<3mm), and high reliability – to serve as a promising solution for transforming a car’s center console display into an effective center channel speaker within the car sound system.
In addition to producing sounds, Dragonfly™ in this configuration is capable of generating robust haptic feedback on the touch screen.
Other Applications
Unlock the potential
Being thin, lightweight, and efficient, Dragonfly™ offers distinct advantages that pave the way for a multitude of potential applications. It provides hardware designers with an exceptional opportunity to create innovative audio solutions that were previously beyond reach.
