What is it?
HiFi-ESP32 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 PCM5100 series DAC with supreme audio quality.
The HiFi-ESP32 Plus represents the next evolution of HiFi-ESP32 boards, featuring the advanced PCM5122 DAC with built-in DSP capabilities. This board maintains the same audio quality as the original HiFi-ESP32 while adding powerful digital signal processing features, including parametric EQ (6 BQs per channel), DRC, and crossover functionality. The PCM5122’s flexible DSP engine can be configured for various audio enhancement scenarios, making it ideal for projects requiring sound tuning (why would you not), and opening the path to create 2.1 systems with PCM5122+PCM5102 master-slave config.
Motivation
Over the past few years, I dedicated my time to developing various solutions using ESP devices. It all began with the ESP8266, which had limited CPU power, restricting it to basic tasks like simple sound alerts. However, with the arrival of the ESP32, everything changed. This new model brought two significantly more capable cores, simultaneously providing a powerhouse for handling communication and real-time decoding. Furthermore, the inclusion of 4MB of PSRAM proved to be crucial, enabling effective buffering for streamed content.
I developed a diverse selection of ESP32 docks that allow for rapid prototyping across the entire spectrum of ESP32 chips. These docks cater to various needs, ranging from small, compact devices resembling toys to large, full-sized speakers. The HiFi-ESP32 is a high-end Hi-Fi DAC offering top-of-the-line audio quality and the lowest noise levels.
Features
| HiFi ESP (discontinued) | HiFi-ESP32 | HiFi-ESP32 Plus | |
|---|---|---|---|
| Docks with | ESP32 Mini Module | ESP32-WROVER-N8R8 or ESP32-S3-WROOM-N8R8 | ESP32-WROVER-N8R8 or ESP32-S3-WROOM-N8R8 |
| DAC | PCM5100A 32-bit Stereo DAC -100 dB typical noise level | PCM5100A 32-bit Stereo DAC -100 dB typical noise level | PCM5122 32-bit Stereo DAC -112 dB typical noise level and DSP |
| Output | Non-amplified stereo output, 2.1V RMS | Non-amplified stereo output, 2.1V RMS | Non-amplified stereo output, 2.1V RMS |
| PSRAM | 8MB (4MB usable) | 8MB (4MB usable for non-S3 ESP32) | 8MB (4MB usable for non-S3 ESP32) |
| Connectivity | WiFi + BT4.2 + BLE Ethernet | WiFi + BT4.2 + BLE W5500 Ethernet (optional) | WiFi + BT4.2 + BLE W5500 Ethernet (optional) |
DSP Features
The new PCM5122 DAC is a more advanced version of the PCM5102 DAC. While it shares the same audio stage, it has a powerful built-in DSP with I2C control. Basically, all the stuff you’d normally need a separate DSP chip for, or would have to burn CPU cycles on the ESP32 to handle.
- Parametric EQ (6 BQs per channel) and crossover capabilities (for cascading DACs)
- Digital volume control (avoids loss of resolution compared to software volume)
- Advanced audio processing features (DRC)
Onboard PSRAM
Audio streaming requires proper buffering to work, even with ESP32 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.
Case
HiFi-ESP32(S3) is mechanically compatible with Raspberry Pi 3/4 cases, tested with transparent ones.
Optional SPI Ethernet module
Every board has a header that allows soldering in the W5500 SPI Ethernet module, which is very easy to find. The only downside is that with the module installed board will not fit the case unless it is cut to accommodate extra height.
Firmware samples
In the software section, two firmware examples are provided. But the editor’s favorite is the squeezelite-esp32 firmware that you can flash directly from your browser using web-installer
Documentation
Both software and hardware documentation can be found on the project’s GitHub. You can follow the project progress at Hackaday
Where to buy
You may support our work by ordering this product at Tindie and Elecrow