Esparagus Media Center

Esparagus Media Center is a series of ESP32 based media center devices. They all run Squeezelite-ESP32 software and have similar media capabilities, but aimed at different use cases. They share a similar look, and compared to my earlier designs, they have a great looking aluminum case.

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Why Esparagus

ChatGPT made me call it that way. I only asked if there is a fruit or vegetable that is phonetically close to ESP32, which is the heart of this device.

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 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 proper Hi-Fi DAC you would not tell a difference to commercial devices standing side by side and costing much more.

Over last few years I see few amazing software products created to deliver audio on the ESP32, like squeezelite-esp32 or euphonium. Esparagus media center devices are 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.

Esparagus HiFi MediaLink

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. It exposes line level output that you can plug into a stereo amplifier. It uses the legendary PCM51 series DAC with supreme audio quality.

Loud Esparagus

Loud Esparagus is aimed to be paired with small-to-medium sized speakers in a small room. It uses a dual MAX98357 Hi-Fi DAC that will output 3W per speaker. Admittedly not much, but well enough for a kid's room or work place. Due to the D-class amp, it barely uses power and can be paired with a standard USB wall charger.

Louder Esparagus

Louder Esparagus is a top-of-the-range model that uses modern highly capable TAS5805M DAC and is aimed to be paired with medium-to-large speaker systems. With 25W per channel stereo output it packs a punch and can easily enlive living quarters or dorm rooms. It is highly efficient, but much more demanding for power when cranked, therefore it uses USB-C Power Delivery to pull up to 65W from the wall power adapter. It can be used both with Wi-Fi and Ethernet (to make sure bad Wi-Fi would not interrupt the stream)

Features

	Hifi ESP	Esparagus HiFi MediaLink	Loud ESP	Loud Esparagus	Louder ESP	Louder Esparagus
Image
DAC	PCM5100A 32bit Stereo DAC	PCM5100A 32bit Stereo DAC -100 dB typical noise level	Dual I2S DAC (MAX98357) with built in D-Class amp	Dual I2S DAC (MAX98357) with built in D-Class amp	Stereo I2S DAC (TAS5805M) with built in D-Class amp	Stereo I2S DAC (TAS5805M) with built in D-Class amp
Power	3x LP5907 3.3 V Ultra-Low-Noise LDO	3x LP5907 3.3 V Ultra-Low-Noise LDO	5V from Mini-USB	5V from USB-C	Up to 26V from external PSU	Up to 20V from USB-C PD
Output	2.1 VRMS Line-level stereo output 3.5mm jack	2.1 VRMS Line-level stereo output 3.5mm jack	2x 3W	2x 3W	2x 23W at 22V Vin	2x 22W at 20V over USB-PD
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
Size		80 x 50 x 20mm		80 x 50 x 20mm		100 x 80 x 38mm

Onboard PSRAM

Audio streaming requires proper buffering to work, even with ESP32 500K of RAM it is a challenging task. All Esparagus boards are based on WROVER modules that have an onboard PSRAM chip.

Board Pinout

Common to every board

	I2S CLK	I2S DATA	I2S WS	PSRAM CE	PSRAM CLK
ESP32	26	22	25	16	17

Peripheral (Loud Esparagus & Esparagus HiFi MediaLink )

	SPI HOST	SPI CLK	SPI MOSI	SPI MISO	OLED DC	OLED CS	OLED RST	WS2812 RGB LED	RELAY EN
ESP32	2	18	23	19	4	5	32	33	21

TAS5805M DAC (Louder Esparagus)

	I2C CLK	I2C DATA	PWDN	FAULT
ESP32	27	21	33	34

Peripheral - OLED Screen and W5500 Ethernet (Louder Esparagus)

	SPI HOST	SPI CLK	SPI MOSI	SPI MISO	LAN RES	LAN CS	LAN INT	OLED DC	OLED CS	OLED RST
ESP32	2	18	23	19	14	5	35	4	15	32

Other Peripheral (Louder Esparagus)

	USB-PD EN	USB-PD POWER GOOD	IR INPUT	WS2812 RGB LED
ESP32	13	36	39	12

Software samples

In the software section two firmware examples 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-readio stream player. It expects playlist as an input in 'data' folder.

Platformio IDE

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

Arduino IDE

Follow the ESP8266Audio library guide.

Squeezelite-ESP32

Squeezelite-ESP32 is a multimedia software suite, that started as 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 connect to all major on-line 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 web-browser. You can use Squeezelite-ESP32 installer for that purpose.

How to flash and configure

Use Squeezelite-ESP32 installer to flash firmware first.


Use `Generic/I2S` profile
Connect device to USB port and select if from the list
Press `Flash` and wait around 2 minutes
(Optional) You may enter serial console to get more information
Device is in recovery mode. Connect to `squeezelite-299fac` wifi network with `squeezelite` password (your network name suffix will be different)
When redirected to captive portal let 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
HiFi and Loud Navigate to NVS Editor section and provide following updates `dac_config`: `model=I2S,bck=26,ws=25,do=22` `display_config`: `SPI,width=128,height=64,cs=5,reset=32,driver=SSD1306,HFlip,VFlip` `led_vu_config`: `type=WS2812,length=1,gpio=33` `spi_config`: `mosi=23,clk=18,host=2,miso=19,dc=4` Press `Commit` button
Louder ESP Navigate to NVS Editor section and provide following updates dac_config: `model=I2S,bck=26,ws=25,do=22,sda=21,scl=27,i2c=45` (STEREO, BTL mode) dac_controlset: `{"init":[{"reg":3,"val":2},{"reg":3,"val":3}],"poweron":[{"reg":3,"val":3}],"poweroff":[{"reg":3,"val":0}]}` (MONO, PBTL mode) dac_controlset: `{"init":[{"reg":3,"val":2},{"reg":3,"val":3},{"reg":2,"val":4}],"poweron":[{"reg":3,"val":3}],"poweroff":[{"reg":3,"val":0}]}` i2c_config: `scl=27,sda=21,speed=400000,port=1` set_GPIO: `33=vcc` Press `Commit` button
Louder ESP, Rev E Update Ethernet configuration, if you're planning to use Ethernet module eth_config: `model=w5500,cs=5,speed=20000000,intr=35,rst=14` spi_config: `mosi=23,clk=18,host=2,miso=19` Press `Commit` button
(Optional) You may change device names to something close to you heart
Exit recovery