The SparkFun Surface Transducer Kit gives you everything you need to turn almost any surface into a speaker. A surface transducer is essentially just a speaker except instead of a cone, the coil is attached to a pad that conducts the vibration into whatever you press it against. Hook it up to the included MP3 player and press it against the nearest table, wall or cardboard box. You can even put it against your head and play music directly into your skull (the ultimate surround sound).

With the included SparkFun Qwiic MP3 Trigger all you need to do is send a simple I²C command and listen to whatever is on your microSD card.

When a USB-C cable is connected to the Qwiic MP3 Trigger the contents of the microSD card appears as a jump drive. Simply plug in the Qwiic MP3 Trigger and you'll be transferring MP3s, no need for drivers and no need for WAV or Vorbis conversion! Sound output is provided via a 3.5mm headphone jack or poke-home connector allowing an external speaker to be connected without soldering. Your supplied speaker is boosted by a Class-D mono amplifier capable of outputting up to 1.4W making it capable of being incredibly loud! Volume is software selectable between 32 levels while equalization can be tuned to be sure your classical hits sound different from your jazz dance routines. If you don't want to deal with any programming, there are four trigger pins. When pin 3 is pulled low the T003.mp3 file will immediately be played. This allows you to start playing sound effects with the touch of a button! By pulling multiple pins down simultaneously the four triggers can play up to ten tracks: T001 to T010. Up to 255 tracks can be loaded onto the SD card and triggered via the I2C interface.

All settings including volume, EQ, and I²C address are stored in NVM and loaded at each power up. The I²C address of the Qwiic MP3 Trigger can be modified via a solder jumper or be assigned using a software command. Multiple Qwiic MP3 Triggers can be chained together on a single bus allowing for simultaneous track mixing and triggering.

The SparkFun Qwiic Connect System is an ecosystem of I²C sensors, actuators, shields and cables that make prototyping faster and less prone to error. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector. This reduces the amount of required PCB space, and polarized connections mean you can’t hook it up wrong.

• 1x Surface Transducer - Large
• 1x SparkFun Qwiic MP3 Trigger
• 1x microSD Card - 1GB (Class 4)
• 1x Jumper Wires M/M - 2 Pack
• 1x Reversible USB A to C Cable - 0.8m
• 1x USB Wall Charger - 5V, 1A

Surface Transducer:

• Datasheet

MP3 Player:

• Schematic
• Eagle Files
• Hookup Guide
• Datasheet (WT2003S)
• What is Qwiic?
• Example Sketch
• GitHub Hardware Info