What is it

Loud-ESP32 is handy, low-cost media streamer device that can be paired with passive speakers. Loud-ESP32 uses a dual MAX98357 Hi-Fi DAC that will output up to 5W per speaker, so it can be powered by a standard USB-C wall charger. Due to the D-class amp, it is highly efficient yet high-quality audio streamer.

Use cases

Loud-ESP32 is a flexible, open-source audio platform designed to fit into both smart homes and custom audio projects.

• Smart Home Audio & TTS
  Integrates with Home Assistant and Music Assistant for high-quality audio playback and text-to-speech announcements. Perfect for notifications, voice alerts, and whole-home audio driven by your smart home automations.
• Multi-Room Audio with Snapclient
  Use Loud-ESP32 as a Snapclient endpoint to create perfectly synchronized multi-room audio systems. Ideal for distributed music playback without proprietary lock-in.
• Standalone Player with Squeezelite-ESP32
  Run Squeezelite-ESP32 for a self-contained network audio player supporting Spotify Connect, AirPlay, and Logitech Media Server (LMS) — no external computer required.
• Educational Projects & Teaching Platforms
  A powerful tool for schools, universities, and technical education. Loud-ESP32 can be used to teach embedded systems, digital audio, networking, and open-source software — ranging from simple audio playback labs to advanced DSP, streaming, and real-time systems projects.
• Research, Prototyping & Experimentation
  Well-suited for rapid prototyping of audio devices, proofs-of-concept, and research projects involving DSP, low-latency streaming, wireless audio, or human-machine interaction.
• A Foundation for Custom Products & DIY Builds
  With all firmware and tooling fully open source, Loud-ESP32 is an ideal base for custom audio devices — whether you’re building a personal DIY project, a small production run, or a community-driven product.

Features

⚠️ Loud boards will connect to passive speakers; you can't use headphones or an external amp.

💡 Need to connect an external amp? Check out HiFi-ESP32 / HiFi-ESP32-Plus and Amped-ESP32 / Amped-ESP32-Plus

💡 Need DSP capabilities? Check out Louder-ESP32 / Louder-ESP32-Plus

💡 Looking for a more feature-packed version? Check out Loud Esparagus / Esparagus Echo

Onboard PSRAM

Audio streaming requires proper buffering to work, even with the ESP32's 500K of RAM; it is a challenging task. For that reason, all Louder-ESP32 board versions have an 8 MB PSRAM chip onboard, connected via a high-speed interface.

Which chip: ESP32 or ESP32-S3?

This board is available with either the 'classic' ESP32 or the newer ESP32-S3. They are not interchangeable for every use case, and picking the wrong one is the single most common support question — here's the short version:

• ESP32-S3 is the newer, more capable chip — more RAM headroom, a faster CPU, and native USB — but it has no Bluetooth Classic radio, so Bluetooth A2DP only works on the original ESP32.
• Squeezelite-ESP32 and standalone Snapclient: pick the classic ESP32. Neither firmware is fine-tuned for the S3 yet, and current S3 support is noticeably laggier.
• ESPHome / Home Assistant media player: pick ESP32-S3. The new Sendspin renderer runs much better on the S3's extra headroom.
• Voice assistant (wake word) in Home Assistant: ESP32-S3 is mandatory — the classic ESP32 doesn't have the RAM/CPU headroom to run it.
• AirPlay 1 & 2 (rbouteiller/airplay-esp32): both chips are fully supported; ESP32-S3 is preferred for its extra performance headroom.

If none of that applies to you and you just want the safe default, pick ESP32-S3 — it's the newer chip. Only choose classic ESP32 if you specifically need Bluetooth A2DP, or plan to run Squeezelite-ESP32/Snapclient today.

Board Pinout

Loud-ESP32

Ethernet

Optional peripheral

Software Options

• Home Assistant smart home audio and notifications. Start from the web-installer, as soon as you configure WiFi, the boards will be discovered by the ESPHome add-in automatically. Dedicated configs can be found in the documentation for simple and stable media-player, experimental sendspin protocol, and experimental snapclient component
• Squeezelite-ESP32 Spotify Connect, AirPlay, Bluetooth or Logitech Media Server. Flash directly from your browser using the web-installer. Configure WiFi using Hotspot (default password: squeezelite). Don't forget to exit Recovery mode when done.
• Snapclient multi-room audio streaming with snapserver. Flash directly from your browser using the web-installer, as soon as you configure the WiFi board will discover the snapserver automatically
• Snapclient (edge) - developer version. Developer's version of the snapclient, less stable and more feature-rich for those who cannot wait for new features to be released. Installed via web-installer, similar to standard snapclient
• AirPlay 1 & 2 with Sendspin and Bluetooth. Native, actively developed AirPlay 1 & 2 firmware (rbouteiller/airplay-esp32) with PTP multi-room sync, an experimental Sendspin renderer, and Bluetooth A2DP on the ESP32 revision. Flash straight from your browser with the web-installer — no toolchain needed. See AirPlay 2 support below for details.
• Your own software. Use Arduino IDE or Platformio IDE and the provided software samples

AirPlay 2 support

Loud-ESP32 runs rbouteiller/airplay-esp32, an open-source AirPlay 1 & 2 receiver you can flash straight from your browser via the web-installer — no PlatformIO or toolchain required. It's a separate firmware image from Squeezelite-ESP32 and Snapclient above, so flash whichever matches how you want to use the board.

• AirPlay 1 & 2 — shows up natively in Control Center and any AirPlay app, with PTP-based multi-room sync
• Sendspin (experimental) — an open multi-room protocol renderer sharing the same output path and volume control as AirPlay
• Bluetooth A2DP on the ESP32 revision — phones and laptops can stream directly whenever AirPlay is idle (the ESP32-S3 revision has no Bluetooth Classic radio)
• OLED status display — track metadata and progress for AirPlay, Bluetooth, and Sendspin alike
• USB audio (UAC) — the ESP32-S3 revision can be built as a USB sound card for a connected computer, sharing the same DAC path
• No on-chip DSP: the MAX98357A has no configuration interface to expose

Using with Home Assistant

Both Loud-ESP32 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

Flashing ESP32-S3

ESP32-S3 boards have two ways of firmware update: (1) similarly to classic ESP32, they can be flashed over built-in UART, or (2) uniquely for S3, over built-in USB host controller. Since it is firmware-controlled, it may be disabled if not used (or, more commonly, not available with factory default empty firmware). When come unflashed ESP32-S3 device comes into a boot loop, with a USB-CDC device appearing and disappearing every second, and requires a special flashing initialisation sequence to get flashed:

• Press the IO0 (FLASH) button and keep it pressed
• Press and release the RESET button. Release the FLASH button.
• ESP32-S3 will enter download mode, and the USB-CDC device will appear and stay available
• Run flashing routine as usual, either through web-serial or esp_tool
• This time, it is not possible to reboot the device over USB, so press RESET once more
• Device will boot normally into firmware, and if USB-CDC is enabled in the firmware, you will be able to flash it normally, download mode and reset sequence will work over USB.
• If you manage to flash firmware without USB-CDC support, you need to go through the above sequence once more

Hardware

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

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