What is it

HiFi Esparagus and HiFi Esparagus S3 are handy, low-cost media devices that will upgrade your legacy audio system with internet streaming capabilities. It exposes line-level output that you can plug into active speakers, a stereo amplifier, or headphones. They use the legendary PCM5100 series DAC with supreme audio quality.

Recent addition – ESP32-S3 version – adds front-facing microphone and RGB LED, so it can also be used as a voice-assist device, providing an off-grid Alexa-like experience for your Home Assistant setup.

Our Crowd Supply campaign to back the manufacturing of the Esparagus series boards was successfully funded, thanks to everyone who made that possible.

Motivation

I did a 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.

Which device is right for me

Features

	HiFi Esparagus	Loud Esparagus	Louder Esparagus	Amped Esparagus
Image
MCU	ESP32-WROVER-N8R8	ESP32-WROVER-N8R8	ESP32-WROVER-N16R8	ESP32-WROVER-N16R8
DAC	PCM5100A 32bit Stereo DAC -100 dB typical noise level	Dual I2S DAC (MAX98357) with built in D-Class amp	Stereo I2S DAC ( TAS5805M ) with built in D-Class amp	PCM5100A 32bit Stereo DAC working with TPA3110D2 D-Class amp
Power	5V over USB-C, 2x LP5907 3.3 V Ultra-Low-Noise LDO for analog section	5V from USB-C	Up to 20V from USB-C PD or up to 26V from generic power adapter	Up to 20V from USB-C PD or up to 26V from generic power adapter
Output, 4Ω	Non-amplified stereo output	2x 3W	2x 32W (4Ω, 1% THD+N)	2x 22W (4Ω, 1% THD+N) at 16V 1x 40W (4Ω, 1% THD+N) at 20V
Output, 8Ω	-	2x 5W	2x 22W (8Ω, 1% THD+N)	2x 25W (8Ω, 1% THD+N) at 22V
PSRAM	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable)	8MB PSRAM (4MB usable)
Peripheral	WS2812B RGB Led SSD1306 128x64 OLED screen (optional)	WS2812B RGB Led SSD1306 128x64 OLED screen (optional)	WS2812B RGB Led SSD1306 128x64 OLED screen (optional)	8xWS2812B RGB Led SSD1306 128x64 OLED screen (optional) Rotary encoder with push button
Connectivity	WiFi BT4.2 BLE	WiFi BT4.2 BLE	WiFi BT4.2 BLE W5500 Ethernet	WiFi BT4.2 BLE W5500 Ethernet
Size	80 x 50 x 20mm	80 x 50 x 20mm	100 x 80 x 38mm	100 x 80 x 38mm
Software support	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

Mic

ESP32-S3 versions of the board have an onboard I2C microphone. It can be used for wake word functionality in the Home Assistant or for custom firmware.

The mic model that I used for testing and validation is the TDK ICS-43432 MEMS microphone

Which software is right for me

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.

Using with Home Assistant

Both HiFi Esparagus versions were created specifically to be used with Home Assistant via ESPHome integration. For both boards, rich configs were pre-created with hardware configuration for common use cases. These include

• media_player component for simple and robust media playback and TTS announcements (with ducking effect)
• Sendspin media player – new experimental protocol for multi-room sync with media controls and more
• An experimental snapclient component that allows near-perfect multi-room sync and seamless integration with Music Assistant
• Another snapclient fork with an implemented 15-band software equalizer and a rich set of EQ presets
• Voice assist config for S3-based boards, allowing local voice-controlled assist and automation

Configurations are being actively maintained and upgraded, new experimental components added for you to test and enjoy

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.

Please find detailed instructions on the linked GitHub

Squeezelite-esp32 Bug causing boot loop

Before version 1681 squeezelite-esp32 had a bug that caused a boot loop with certain LMS servers when RGB LED was used for visualizations. It seems to be fixed in 1681, but the quick workaround is to clear led_vu_config NVS setting.

Squeezelite-esp32 reboots and connection drops

The default configuration of the squeezelite-esp32 runs automatic discovery of the available LMS server nearby. In fact it depends on it so much that in case the LMS service is not found on the network, it will reboot automatically (every few minutes).

In many cases, if you use squeezelite for Airplay and Spotify only and don't have LMS servier, you need to disable discovery altogether. Currently disabling Squeezelite in the GUI does not work correctly, it places too much spaces between the commands in the autoexec command. Following autoexec1 NVS setting can be used to disable it:

squeezelite -o i2s -s -disable -b 500:2000 -C 30 -d all=sdebug

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

Restocking & Availability

New restock batches are regularly ordered from the factory, and I plan to keep all versions available at least until the next board revision is released. For current availability, you can also check the official reseller Elecrow.

USA shipping Update

Due to the new tariffs introduced by the Trump administration, standard shipments are temporarily on hold. However, shipping to the US has now resumed via UPS, though rates are currently quite high. I’ll fully resume regular shipping as soon as the restrictions are lifted. In the meantime, you may consider ordering through Elecrow.

Sponsorship & Community Support

If you’re working on an open-source project, an educational initiative, or any pro-bono/volunteer effort, feel free to reach out for sponsorship details. I’ll do my best to provide discounts or even free boards.

Custom Design & Consultation

If you’re interested in a custom design based on or inspired by my boards, I also offer contract design work and consultation when needed.

Most orders are shipped the next business day morning. All shipments are tracked. Delivery time in the EU is 3-7 days, outside 2-3 weeks, depending on the distance. After 30 days, the package is considered lost - reach out for a refund or replacement.