Embedded audio
Cargo Bike Soundsystem
A powerful mobile sound system built on a three-wheel cargo bike platform. The vision was to modify a cargo bike and turn it into a mobile sound source for outdoor parties and events. The main challenge was to squeeze as much power as possible into such a form factor while keeping it mobile. Even though space was limited to 350 × 900 × 350 mm, we delivered a 1.3 kW RMS sound chain with on-board DSP for fine-tuning.
About the project
The project requirements were a cargo bike platform, 1 kW RMS of power and 6 hours of battery-powered playback. We started by selecting amplifier modules and speaker drivers. We then designed a custom PCB with a preamp stage feeding an external DSP for the digital crossover. From there, the audio signal went to class D amplifiers, with an analog LC crossover for the mid-high speakers.
The bass-reflex subwoofer was designed to boost output around 70 Hz, extending the low-frequency response. For mobile power, we designed a LiFePO4 battery bank with an AC inverter. In the end, the solution proved very efficient and met its targets.
Crucially, because the setup is mobile, it had to be durable enough to withstand vibration, impacts and water. It has already been used successfully at multiple events.
