# HiFi Plus Raspberry Pi Hat
Raspberry Pi Audio Hat with DSP-enabled PCM5122 DAC and PCM1863 ADC with line-in and mic inputs
- **Seller:** [Sonocotta store](https://lectronz.com/stores/sonocotta), Warsaw, Mazowieckie, Poland
- **Price:** $20.00 (USD, before shipping and taxes)
- **Availability:** Sold out
- **Categories:** Audio, Raspberry Pi, Home automation
- **Country of origin:** Poland
- **Product page:** https://lectronz.com/products/hifi-raspberry-hat-plus
## Links
- [Documentation](https://hackaday.io/project/201762-raspberry-pi-audio-hats)
- [Code](https://github.com/sonocotta/raspberry-media-center)
## Images
## Description
## What is it?
Raspberry HiFi Plus Hat is an upgraded version of the [base model](https://lectronz.com/products/hifi-raspberry-hat) that uses a more advanced PCM5122 DAC and adds an audio-grade PCM1863 ADC onboard. The main benefit of using PCM5122 is a built-in digital volume control that makes sure that audio resolution is not lost at low volume. It also has built-in DSP with 6x BQ filters, but software support in Linux for it is absent at the moment, so you might need to develop it yourself (or wait for it to be added by the community).
The HiFi Plus Hat is fairly similar functionally to [HifiBerry DAC+ ADC](https://www.hifiberry.com/docs/data-sheets/datasheet-dac-adc/), but developed from scratch to validate DAC/ADC schematics for the [sister product](https://github.com/sonocotta/esp32-audio-dock/) based on the ESP32
### Key features
- [PCM5122](https://www.ti.com/product/PCM5122) DAC with line-out level output
- -112 dB typical noise level
- 2.1V RMS output
- Up to 32-bit resolution
- Up to 384 kHz sampling rate
- Digital volume and analog gain control
- Built-in DSP with 6xBQ filters, DRC, AGL
- I2S + I2C interface
- [PCM1863](https://www.ti.com/product/PCM1863) ADC with line-level and analog mic inputs
- -110 dB typical noise level
- 2.1V RMS output
- Up to 32-bit resolution
- Up to 192 kHz sampling rate
- Software-controlled gain (-12..32 dB)
- I2S + I2C interface
## Why did I build it
I'm a huge fan of smart home solutions, specifically based on the [Home Assistant](https://www.home-assistant.io/) ecosystem. With the [Sendspin protocol](https://www.sendspin-audio.com/) introduction, it becomes possible to ingest external audio sources (Vinyl player, CD, etc) into the [Music Assistant](https://www.music-assistant.io/), so that they later can be distributed across connected speakers. HiFi Plus Hat is my first approach to this problem, based on the Raspberry platform (for ease of prototyping), and a stepping stone before an ESP32-based device with similar functionality can be created
## Use cases
**Raspberry HiFi-Plus Hat** is a flexible, open-source audio platform designed to fit into both smart homes and custom audio projects.
* **Smart Home Audio, TTS & Automation Node**
Integrates with Home Assistant and Music Assistant for high-quality playback, text-to-speech, and event-driven announcements. Functions as both an audio endpoint and a networked automation node for sensors, triggers, and smart home workflows.
With added ADC, it also allows you to ingest audio sources (vinyl or CD players) into smart home audio solutions, serving as a bridge between old audio gear and modern smart homes
* **Multi-Room Audio Infrastructure**
Use **HiFi Raspberry Plus Hat** as a Snapclient server and endpoint for perfectly synchronized distributed audio. Ideal for open, vendor-neutral whole-home or commercial audio systems.
* **Standalone Network Player & Streaming Hub**
Run LMS/Squeezelite for a self-contained streaming device supporting Spotify Connect, AirPlay, and Logitech Media Server — no external computer required.
* **Embedded Audio Processing & DSP Platform**
Execute real-time digital signal processing, filtering, effects, or audio analysis directly on-device. Suitable for smart speakers, alert systems, acoustic sensing, and custom audio interfaces.
* **Educational Platform for Systems & Networking**
A practical teaching platform for embedded Linux-style workflows without full SBC overhead — covering networking, streaming protocols, real-time processing, IoT architectures, and open-source audio systems.
* **Rapid Prototyping for Connected Products**
Designed for fast iteration of networked hardware products — from smart audio devices and notification systems to interactive kiosks and connected consumer electronics.
* **Open Platform for Custom Products & DIY Builds**
With fully open firmware and tooling, **HiFi Raspberry Hat** provides a flexible foundation for personal projects, research platforms, or commercial device development.
## Features
| | [HiFi Raspberry Hat](https://lectronz.com/products/hifi-raspberry-hat) | **Raspberry HiFi Plus Hat** |
|---|---|---|
| Image |  |  |
| Compatible with | Every Pi | Every Pi |
| DAC | PCM5100A 32-bit Stereo DAC | PCM5122 32-bit Stereo DAC |
| Output | 2.1 VRMS Line level output -100 dB typical noise level | 2.1 VRMS Line level output -112 dB typical noise level |
| IR input | ✅ | ✅ |
| ADC | ❌ | PCM1863
ADC with line-level and analog mic inputs
-110 dB typical noise level |
| DSP features | ❌ | Digital volume, analog gain, 6x BQ filters, DRC |
| Mechanical dimensions (WxHxD) | 65mm x 30mm x 15mm | 65mm x 30mm x 15mm |
| Power requirement | 5V from the host Pi | 5V from the host Pi |
⚠️ *HiFi boards require an external amplifier or active speakers; you can't connect passive speakers to it.*
💡 *Need to connect speakers as well? Check out [Amped Raspberry Hat](https://lectronz.com/products/amped-raspberry-hat) and [Amped Raspberry Media Center](https://lectronz.com/products/amped-raspberry-media-center)*
💡 *Need only speakers output? Check out [Loud Raspberry Hat](https://lectronz.com/products/loud-raspberry-hat) and [Loud Raspberry Media Center](https://lectronz.com/products/loud-raspberry-media-center)*
💡 *Need more powerful DSP? Check out [Louder Raspberry Hat](https://lectronz.com/products/louder-raspberry-hat), [Louder Raspberry Hat Plus](https://lectronz.com/products/louder-raspberry-hat-plus) and [Louder Raspberry Media Center](https://lectronz.com/products/louder-raspberry-media-center)*
## Board Pinout
| | I2S CLK | I2S DATA | I2S WS | IR INPUT |
|--------------------|---------|--------------------|--------|----------|
| Raspberry Pi | 18 | 21 | 19 | 17 |
## How to use
You need nothing more than an SD card with a Raspbian image and a USB-C power brick. You can use any distribution you like. The only change you need to make to enable hardware is to add 3 lines to the `/boot/config.txt`
```
dtoverlay=gpio-ir,gpio_pin=17
dtoverlay=hifiberry-dacplusadc
```
To test the line input capture you may use the below snippet
```
arecord -D hw:0,0 -f S16_LE -r 48000 -c2 | aplay -D hw:0,0 -f S16_LE -r 48000 -c2 --buffer-time=50000
```
## Other software options
The project repository provides a few examples with build instructions, including [Volumio setup](https://github.com/sonocotta/raspberry-media-center#volumio) instructions, among others.
## Hardware
Please visit the [hardware](https://github.com/sonocotta/raspberry-media-center/tree/main/hardware) section of the project repo for board schematics and PCB designs. Note that PCBs are shared as multi-layer PDFs as well as Gerber archives.
### IR reader
Please follow [this guide](https://github.com/sonocotta/raspberry-media-center?tab=readme-ov-file#ir-reader) to configure an IR reader
## 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.
## 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.
## Shipping policy
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.