What is it?

The Loud Raspberry Hat is a cost-effective version of the Loud Raspberry Media Center. It combines the power of the Raspberry Pi SBC and the Hi-Fi audio capabilities of the Analog Devices MAX98357A DAC.

1X	2X

Loud Raspberry Hat has the same DAC and audio circuitry in a cost-efficient Hat form. The 1X version can be used with any Raspberry Pi, while Raspberry Pi 5 users can use two pairs of speakers independently on the 2X version. Hat will pull the juice from the Pi's 5V line, or power the Pi itself using screw connectors, so you can make sure enough power is delivered to both boards.

Why did I build it

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 is special about the Raspberry eco-system is, of course, its community support. Being a not-so-strong software developer, I often have to rely on the work that other people did and baked into the base Raspbian image. Attaching a DAC, Ethernet, and IR reader is as simple as adding 3 lines into config.txt file. All the device tree definitions, kernel drivers, and dependency packages are already in place, believe it or not.

Sure, compared to the ESP32 platform, it is not as lightweight. It requires more power, it takes some time to boot. But when it comes to rapid development, there is nothing like the Raspberry Pi.

Loud Raspberry Hat uses a quad MAX98357 HiFi DAC with a built-in highly efficient D-class amp to deliver 3 to 5W of music power directly to your speakers. It is not too loud, but it is very simple to use and fun to play with. It powers from a standard USB-C power source, like a phone charger or a standard 5V wall adapter delivering a few amps.

Use cases

Loud Raspberry 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.
• Multi-Room Audio Infrastructure Use Loud Raspberry 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.
• Networked Sensor & Interface Controller Combine audio output with GPIO control, sensors, buttons, displays, or actuators. Ideal for interactive installations, smart appliances, voice feedback devices, or industrial status systems.
• 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, Loud Raspberry Hat provides a flexible foundation for personal projects, research platforms, or commercial device development.

Features

	Loud Raspberry Hat	Loud Raspberry Hat 2X	Loud Raspberry Media Center
Image
Compatible with	Every Pi	Raspberry Pi 5	Raspberry Pi Zero (W), Raspberry Pi Zero2 W
DAC	Dual MAX98357 DAC with built in D-Class amp	Quadruple MAX98357 DAC with built in D-Class amp	Dual MAX98357 DAC with built in D-Class amp
Output	5W per channel on 4Ω load (3W on 8Ω)	5W per channel on 4Ω load (3W on 8Ω)	5W per channel on 4Ω load (3W on 8Ω)
IR input	❌	❌	✅
RGB LED	❌	❌	✅
Onboard Serial Bridge	❌	❌	✅
Wizznet W5500 Ethernet	❌	❌	✅
Mechanical dimensions (WxHxD)	65mm x 30mm x 15mm	65mm x 30mm x 15mm	88mm x 38mm x 100mm
Power requirement	5V from the host (up to 2A) or 5V from screw connector (powering host)	5V from the host (up to 4A) or 5V from screw connector (powering host)	5V USB-C power adapter (up to 3A)

⚠️ 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 Raspberry Hat and HiFi Raspberry Media Center

💡 Need DSP capabilities? Check out Louder Raspberry Hat, Louder Raspberry Hat Plus and Louder Raspberry Media Center

Board Pinout

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=max98357a,sdmode-pin=5

Other software options

The project repository provides a few examples with build instructions, including Volumio setup instructions, among others.

Hardware

Please visit the 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.

PCB diagram

1X	2X

Power considerations

Below are the power requirements for different Pi models

Consider each 5W of expected audio output to be another 1A of the current budget and buy a reasonable power source capable of delivering the sum of Pi and audio requirement with a reasonable margin of 15%+

In the extreme scenario, using all 4 channels with 4 Ohms load with Pi5, you'd need (3A [Pi] + 4A [audio]) * 1.2 = 8.4A or 42W, round up to 50W.

Raspberry Pi 5 note

Raspberry Pi 5 is the first one that allows the user to drive multiple I2S data lines using the same interface. What it means in practice is that while all older Pis have just 3 I2S lines (CLK, WS, DATA), Pi5 supports up to 4 Data lines (CLK, WS, D0, D1, D2, D3), capable of driving 4 independent audio interfaces.

2X Raspberry Pi hats support alternative data lines. You need to short some solder bridge to use it, though. It allows configuring Hats to use different pins and stack them together to create 4 individual stereo interfaces (8 channels in total) using the same device.

By default, the 2X hat uses pins 21,23 for data, with the possibility to switch to pins 25 and 27 with solder bridges and stack 2 boards together.

Loud Hat

The device tree that can utilize all channels and DACs on and off properly is a work in progress. But a quick and dirty way to enable all channels is to use hifiberry-dac8x device tree. It lacks enable pins, and thus they need to be permanently switched on in the software.

The configuration value that allows this is quite simply

dtoverlay=hifiberry-dac8x

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.

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.

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.