What is it

Esparagus HiFi MediaLink is a handy low-cost media device, that will upgrade your legacy audio system with cutting-edge internet streaming capabilities and enhance your audio experience.

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Motivation

I did few audio projects in the past, some using ESP32, some using larger Orange Pi and Raspberry Pi devices. Each has its pros and cons, and with each iteration, I'm trying to focus on the details that were working best for me, while actually using them.

What I like about ESP32 is how lightweight it is. It barely draws power, so you may not care to turn it off at all. It boots in seconds and is ready for use in a snap. Still, it is capable and works at par with Linux SBC solutions for audio applications while costing a fraction of their price. Combined with a proper Hi-Fi DAC you would not tell a difference to commercial devices standing side by side and costing much more.

Over the last few years, I have seen a few amazing software products created to deliver audio on the ESP32, like squeezelite-esp32 or  euphonium. Esparagus HiFi MediaLink is designed specifically to run these great pieces of software and bring a new life into aging audio equipment that most of us have at home, but do not use that much these days, since it is not working with Spotify and the family.

Features

	ESP Audio Duo	Loud Esparagus	Hifi ESP	HiFi Esparagus	Louder ESP32	Louder Esparagus
Image
Docks with	ESP32 Mini Module	ESP32-WROVER-N8R8 onboard	ESP32 Mini Module	ESP32-WROVER-N8R8 onboard	ESP32-WROVER-N16R8 onboard	ESP32-WROVER-N16R8 onboard
DAC	Dual I2S DAC (MAX98357) with built in D-Class amp	Dual I2S DAC (MAX98357) with built in D-Class amp	PCM5100A 32bit Stereo DAC	PCM5100A 32bit Stereo DAC -100 dB typical noise level	Stereo I2S DAC (TAS5805M) with built in D-Class amp	Stereo I2S DAC ( TAS5805M ) with built in D-Class amp
Power	5V from Mini-USB	5V from USB-C	5V from USB-C	5V from USB-C	Up to 26V from external PSU	Up to 20V from USB-C PD
Output, 4Ω	2x 3W	2x 3W	Non-amplified stereo output	Non-amplified stereo output	2x 32W (4Ω, 1% THD+N)	2x 32W (4Ω, 1% THD+N)
Output, 8Ω	2x 5W	2x 5W	-	-	2x 22W (8Ω, 1% THD+N)	2x 22W (8Ω, 1% THD+N)
PSRAM	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable) Onboard	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable) Onboard	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable) Onboard
Peripheral		External WiFi Antenna, WS2812B RGB Led, SSD1306 128x64 OLED screen (optional)		External WiFi Antenna, WS2812B RGB Led, SSD1306 128x64 OLED screen (optional)		External WiFi Antenna WS2812B RGB Led SSD1306 128x64 OLED screen (optional), IR receiver, W5500 SPI LAN
Connectivity	WiFi + BT4.2 + BLE	WiFi + BT4.2 + BLE	WiFi + BT4.2 + BLE	WiFi + BT4.2 + BLE	WiFi + BT4.2 + BLE	WiFi + BT4.2 + BLE Ethernet
Size	39 x 31 x 20mm	80 x 50 x 20mm	39 x 31 x 20mm	80 x 50 x 20mm	86 x 56 x 20mm	100 x 80 x 38mm
Software support	Arduino samples, ESPhome config	Arduino samples, squeezelite-esp32, snapcast, ESPhome config	Arduino samples, squeezelite-esp32, snapcast, ESPhome config	Arduino samples, squeezelite-esp32, snapcast, ESPhome config	Arduino samples, squeezelite-esp32, snapcast, ESPhome config	Arduino samples, squeezelite-esp32, snapcast, ESPhome config

Onboard PSRAM

Audio streaming requires proper buffering to work, even with ESP32 500K of RAM it is a challenging task. Esparagus HiFi MediaLink is based on a WROVER module that has an onboard PSRAM chip.

Board Pinout

Audio

Peripheral

Software samples

In the software section two firmware examples are provided.

• esp32-i2s-bare is base I2S implementation based on ESP-IDF implementation directly.
• esp32-i2s-esp8266audio is based on excellent ESP8266Audio library (it works with the whole ESP range, don't get fooled by the name), providing minimum code implementation.
• esp32-i2s-web-radio is based on the same library, providing minimum web-radio stream player. It expects a playlist as an input in the 'data' folder.

Platformio IDE

All samples are provided as Plarformio IDE projects. After installing it, open the sample project. Select the proper environment based on your dock. Run the Build and Upload commands to install necessary tools and libraries, and build and upload the project to the board. Communication and proper upload method selection will be handled by IDE automatically.

Arduino IDE

Follow the ESP8266Audio library guide.

ESPHome and Home Assistant

Being an ESP32-based device, you can easily integrate it into your Home Assistant using ESPHome. Start with esphome web installer, which will give you ESPHome base install and WiFi configuration in minutes. Some S2/S3 boards have issues with we-installer, you may need to use Adafruit flasher instead with binaries pulled from the HA.

Next, navigate to your Home Assistant (assuming you have your ESPHome integration installed), and adopt the newly created node

ESPHome will give you ESPHome configs for Solo board running with ESP32-S2/S3, as well as Duo/HiFi-ESP and Louder ESP working with ESP32.

Few words of explanation.

• media_player publishes the media player into the Home assistant, so you can use it together with the native player or Music Assistant. You have a volume knob in the HA as well.
• 
• Volume set up to 50% on player start. Especially for Louder-ESP32, this is helpful :)

Bonus - automation example

The true power of the native speaker in the eHA is the use of automation. One example that I find useful. This simple automation will be pronounced every hour between 8 AM and 9 PM. Another one is used to pronounce bedtime, you get the point...

Squeezelite-ESP32

Squeezelite-ESP32 is a multimedia software suite, that started as a renderer (or player) of LMS (Logitech Media Server). Now it is extended with

• Spotify over-the-air player using SpotifyConnect (thanks to cspot)
• AirPlay controller (iPhone, iTunes ...) and enjoy synchronization multiroom as well (although it's AirPlay 1 only)
• Traditional Bluetooth device (iPhone, Android)

And LMS itself

• Streams your local music and connects to all major online music providers (Spotify, Deezer, Tidal, Qobuz) using Logitech Media Server - a.k.a LMS with multi-room audio synchronization.
• LMS can be extended by numerous plugins and can be controlled using a Web browser or dedicated applications (iPhone, Android).
• It can also send audio to UPnP, Sonos, Chromecast, and AirPlay speakers/devices.

All Esparagus boards are tested with Squeezelite-ESP32 software. It can be flashed using nothing but a web browser. You can use Squeezelite-ESP32 installer for that purpose.

How to flash and configure

Use Esparagus Squeezelite-ESP32 installer to flash the firmware. It has been preconfigured to work with Esparagus boards and will configure all hardware automatically.

Select correct device first
Connect the device to USB port and select it from the list
Press Flash and wait around 2 minutes
(Optional) You may enter the serial console to get more information, like device IP and boot logs
Device is in recovery mode. Connect to squeezelite-299fac wifi network with squeezelite password (your network name suffix will be different)
When redirected to the captive portal let the device scan wifi network and provide valid credentials
You can use provided IP address (http://192.168.1.99/ on the screenshot) to access settings page
(Optional) You may change device names to something close to your heart
Exit recovery

You can use it now

Bluetooth	Spotify Connect	AirPlay	LMS Renderer

Hardware

Esparagus HiFi MediaLink

Please visit the hardware section for board schematics and PCB designs. Note that PCBs are shared as multi-layer PDFs as well as Gerber archives.

Boxed

Esparagus HiFi MediaLink

PCB

Esparagus HiFi MediaLink