# Louder Raspberry HAT Plus

> Open-source Raspberry Pi audio HAT featuring TAS5825M Class-D amplifier with integrated DSP, delivering 32W per channel at 8 ohms. Includes 15-band parametric EQ, FIR filtering, DRC, IR input, and onboard step-down converter to power the Pi from 7-26V.

## Quick Facts

- **Brand:** Sonocotta
- **Board Type:** raspberry-pi-hat
- **Price:** ~$25
- **Product Readiness:** consumer
- **CPU:** N/A (HAT expansion board — uses host Raspberry Pi CPU)
- **CPU Architecture:** N/A (HAT)
- **RAM:** N/A (HAT)
- **Flash:** N/A (HAT)
- **Power:** 7-28V DC
- **Operating Voltage:** 3.3V
- **Dimensions:** 65mm x 56mm x 20mm

## Connectivity

- **Wifi:** false
- **Bluetooth:** false
- **Zigbee:** false
- **Ethernet:** false

## Open Source

- **Status:** fully-open
- **Firmware:** Yes
- **Schematics:** Yes
- **PCB Layout:** Yes
- **License:** GPL-3.0

## Compatible Firmware

volumio, squeezelite, snapcast, music-assistant, home-assistant-voice

## Use Cases

- hi-fi-audio
- multi-room-audio
- network-audio-player
- dsp-audio-processing
- text-to-speech
- smart-home
- music-player
- ir-remote-control
- internet-radio

## Components

- **TAS5825M** (audio-amplifier): Texas Instruments 38W stereo closed-loop Class-D amplifier with integrated DAC and advanced DSP featuring 15-band PEQ, 128-tap FIR, 3-band DRC, and speaker protection. Supports I2S/TDM input at up to 192kHz in a 5x5mm VQFN-32 package. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftas5825m&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)
- **ir-receiver** (sensor): Infrared receiver connected to GPIO 17 for decoding standard consumer IR remote control signals (38kHz carrier). Enabled with a single dtoverlay line in /boot/config.txt. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.vishay.com%2Fdocs%2F82491%2Ftsop382.pdf&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)
- **dc-dc-step-down** (power-management): Onboard buck converter accepting 7-26V input and providing regulated 5V at up to 3A continuous output to power the host Raspberry Pi through the GPIO header. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftps54331&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)

## Protocols

- **I2S**
- **I2C**

## GPIO Map

| Pin | Name | Type | Functions |
|-----|------|------|-----------|
| GPIO 2 | I2C Data (SDA) | — | — |
| GPIO 3 | I2C Clock (SCL) | — | — |
| GPIO 4 | DAC Power Down | — | — |
| GPIO 17 | IR Input | — | — |
| GPIO 18 | I2S Bit Clock (BCLK) | — | — |
| GPIO 19 | I2S Data (DIN) | — | — |
| GPIO 21 | I2S Word Select (LRCLK) | — | — |

## Available Software

- **[Volumio]()** (open-source)
- **[Music Assistant]()** (open-source)
- **[Home Assistant]()** (open-source)
- **[Squeezelite / LMS]()** (open-source)
- **[Snapcast / SnapClient]()** (open-source)

## Description

The Louder Raspberry HAT Plus is a high-power audio expansion board designed by Sonocotta in Poland for all Raspberry Pi models. Built around the Texas Instruments TAS5825M, it combines a high-resolution DAC, a fully programmable DSP, and a Class-D power amplifier into a single compact HAT. The board accepts 7-26V external DC power and includes an onboard step-down converter that supplies 5V at up to 3A back to the host Pi, so only one power supply is needed for the entire system.

The TAS5825M DSP offers 15-band parametric equalization per channel, 128-tap FIR filtering, 3-band dynamic range compression, automatic gain limiting, and advanced speaker protection including thermal foldback and excursion limiting. Audio arrives from the Pi over the I2S bus at sample rates up to 192kHz, and the amplifier drives speakers directly with up to 32W per channel into 8 ohm loads or 45W into 4 ohm loads at 20V supply. An IR receiver on GPIO 17 enables remote control integration with a single config.txt line.

The board is fully open source with schematics and PCB gerbers published on GitHub under GPL-3.0. It works out of the box with Volumio, Music Assistant, Home Assistant, Squeezelite/LMS, and Snapcast for multi-room audio. A dual-DAC 2X variant is also available for 2.1 speaker configurations with hardware crossover filters. The HAT measures just 65mm by 56mm and includes a 40-pin adapter for compatibility with all Pi models.

## Where to Buy

- [Tindie](https://openhardware.directory/r?to=https%3A%2F%2Fwww.tindie.com%2Fproducts%2Fsonocotta%2Flouder-raspberry-hat-plus%2F&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export) — $25.00

## Resources

- [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.tindie.com%2Fproducts%2Fsonocotta%2Flouder-raspberry-hat-plus%2F&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)
- [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fsonocotta%2Fraspberry-media-center&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)
- [hackaday](https://openhardware.directory/r?to=https%3A%2F%2Fhackaday.io%2Fproject%2F195272&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)
- [datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Ftas5825m&ref=openhardware.directory&product=louder-raspberry-hat-plus&source=md-export)

## Tags

`raspberry-pi`, `audio`, `amplifier`, `dac`, `dsp`, `class-d`, `i2s`, `open-source`, `hat`, `tas5825m`, `hi-fi`, `multi-room`

## Images

![Louder Raspberry HAT Plus](https://nbg1.your-objectstorage.com/openhardware-directory/entities/louder-raspberry-hat-plus/782abff13234.jpeg)

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