Applications and Implications

What will it do?

Symphoni is a retro-futuristic music device that brings together tactile interaction and modern streaming. It allows users to play Spotify tracks/albums/playlists using custom vinyl-style NFC tags. When a tag is placed on the turntable, the system reads the playlist ID encoded in it and connects to the user's phone via Spotify Connect to begin playback. There is a bluetooth speaker which allows playback from the Spotify Connect Device.

The device includes physical buttons and rotary encoders for controls like play/pause, next/previous, and volume adjustment. A display shows the current songs information, such as title, artist, and album art, creating a rich and immersive audio-visual experience. The entire system is housed in a beautifully crafted enclosure that resembles a turntable, with a spinning platter powered by a small motor to simulate traditional vinyl playback.

The NFC tags can be written using a companion app which allows the user to write tracks, albums or playlists to any NFC Records when placed on the turntable

Who's done what beforehand?

There have been a few notable projects that inspired Symphoni. For instance, the Spotify Box by Spotify and various maker communities demonstrated the potential of using NFC tags to trigger Spotify playlists. Most of the projects use an Raspberry Pi.

• Rpi-Spotify E-INK Display
• DIY Spotify Car Thing
• Spotify smart speaker using ESP32
• RFID Record Player - RPi

Projects like RFID Record Player and ESP32-based music streamers have explored playlist control using tags. While levitating turntables and NFC-triggered music devices exist, there hasnt been a seamless, well-packaged integration of NFC Spotify control, custom controls, and display with aesthetic design for personal use. Symphoni stands out by combining handcrafted design, tactile controls, and a display interface in one cohesive unit.

What sources will you use?

For the design and development of Symphoni, I will be using a combination of online resources, tutorials, and documentation. The primary sources include:

ESP32 Libraries and Documentation:
• SpotifyEsp32 - for Spotify API Communication with ESP32
• Spotify API Documentation - for understanding how to interact with Spotify's API and implement features like playlist control and song information retrieval.
• ESP32 A2DP - Library for A2DP Bluetooth Sink and Source
• Audio Tools Library for Audio

What will you design?

Enclosure

The enclosure will be designed to resemble a traditional turntable, with a spinning platter and a sleek, modern aesthetic. The design will incorporate space for the ESP32 board, NFC reader, motor driver, and other components. The enclosure will be made from wood and acrylic, with a focus on craftsmanship and attention to detail.

The enclosure will also include cutouts for the display, buttons, sliders and rotary encoders, ensuring that all components are easily accessible and functional. The design will prioritize user experience, making it easy to interact with the device while maintaining a visually appealing appearance.

PCB

The PCB will be designed to integrate all the necessary components, including the ESP32, NFC reader, motor driver, and audio output. The design will focus on compactness and efficiency, ensuring that all components fit within the enclosure while maintaining optimal performance.

I will be designing 2 different PCBs:Main PCB and Bluetooth Speaker PCB

Main PCB: The main PCB will be responsible for Spotify Communication, turntable control and Display.

Bluetooth Speaker PCB: The Bluetooth Speaker will be driven entirely based on this PCB working on a ESP32 Wroom at it's center

What materials and components will be used?

The main body will be made by using 18mm plywood cross sections and the control platform will be made using 3D printing/CNC milled wood. The knobs and buttons will be 3D Printed.

The finishing will be done using veneer sheets or leather

The turntable and the records will be made using acrylic sheet.

The main components used in the project will include:

• ESP32 Wroom 32
• NFC Reader (RC522 Based)
• Motor Driver (MOSFET Driven)
• Rotary Encoder
• Buttons (Tactile Push Buttons)
• Slider Potentiometer
• SPI TFT Display (2.2")
• PCM5102 I2S DAC
• Audio Amplifier
• Speaker Drivers 4 Ohm 5W
• Power Supply (12V)
• Buck Converter :12V to 5V/3.3V

Where will come from?

The electronics components will primarily be from the Fablab Inventory and online websites such as Robu.in and Hubtronics.

I will be upcycling my old speaker drivers for this project

The 18mm Plywood is available in the lab. The veneer/leather and the finishing material will be purchased from local market

How much will they cost?

The estimated cost of the materials and components for Symphoni is as follows:

Speaker Module

Player Module

What parts and systems will be made?

The bluetooth speaker PCB and the main PCB will be designed and fabricated in the lab. The DC Motor driver will be made using N-Channel Mosfet. The turntable system will be made using DC Motor and wheel system.

The I2S DAC, Amplifier board and speakers will be purchased from online stores.

What processes will be used?

The processes used in the project will include:

• 3D Printing for knobs and buttons
• CNC Milling for the control platform and enclosure
• PCB Design and Fabrication for the main PCB and Bluetooth speaker PCB
• Laser Cutting for acrylic turntable and records
• Assembly of electronic components and wiring
• Finishing using veneer or leather

What questions need to be answered?

Some of the questions that need to be answered during the development of Symphoni include:

• How to ensure seamless communication between the ESP32 and Spotify API?
• What is the best way to design the enclosure for optimal user experience?
• How to integrate the NFC reader and ensure reliable tag detection?
• What is the most effective way to implement tactile controls for playback and volume adjustment?
• How to optimize the audio output for high-quality sound reproduction?

How will it be evaluated?

The success of Symphoni will be evaluated based on the following criteria:

• The Record is easily writable and readable by the system
• The device can seamlessly connect to Spotify and play tracks/albums/playlists using NFC tags
• The tactile controls (buttons, rotary encoders, sliders) function smoothly and intuitively
• The display provides clear and informative song information
• The overall design is aesthetically pleasing and functional
• The audio output is of high quality and meets user expectations