• Introducing Raspberry Pi Hats

    andriy.malyshenko • 09/23/2024 at 11:45 • 0 comments

    One of the cool features of the Raspberry Media Center devices was the neat Aluminum case that you can place pretty much anywhere around your stereo system. One of the drawbacks of that design was the limited space and wifi antenna constraints, in other words, it would only work with Raspberry Pi Zero. Which is plenty, but not for everyone.

    Another obvious drawback is the added cost connected to non-functional features. Not everyone cares much for the case, as I'm sure.

    The Raspberry Pi Hat series is here to address both of those issues and one more. It will cost about half the Media Center cost, and pair with pretty much any Pi out there.

    Bonus feature - Pi5 supports now multiple data lines on the I2S interface (up to four to be precise). Thus you can have multiple cards on the same Hat, or stacking them together yields 4 stereo outputs, 8 channels in total. That's a call for a multi-room system right there!

    HiFi Hat is a HiFi Media Center in compact shape, doubling the audio inputs. Loud Hat is the same story, but using the MAX98357 DAC, four of them to be precise.

    Louder Hat uses TAS5805M DAC, just like the Louder Media Center. In that case, doubling thick didn't work, since (a) it needs a 5V drop-down, and oh boy, Pi5 is hungry for it! And (b) TAS5805 needs a good thermal interface and for now, I'm not ready to promise this small board can survive both. Even in that basic configuration, it requires good ventilation. But hey, they used to take whole shelves of those older amps of the same capability, didn't they?

    The last one in the family does not have a Media Center Equivalent yet, HiFi Plus uses the same DAC as the HiFi Hat but adds a TPA3110 D-class amp so you can use it with speakers directly. This is very much an experimentation platform for me since I want to play around analog regulators with it (work in progress).

    I'm planning to publish all the Hats to Tindie soon, allowing me to fund those experiments moving forward.

  • Loud model is the last one in the series

    andriy.malyshenko • 05/17/2024 at 09:35 • 0 comments

    Following the Louder model, a smaller version came into existence. Named Loud Raspberry, It is based on the very well-known MAX98357A DAC. Compared to the Louder model is it not as loud (obviously), delivering 'just' 5W of music power per channel. 

    Why would you want one? For starters, it is much easier to use, just like the HiFi model you need just one line in the config file, enabling built-in overlay. Another reason is that with just a 3 Amp power requirement, you can use it with a standard wall power adapter (any modern phone charger will do). Since everyone has a few laying around, it is easier to get started.

    To get a feeling, how much is the humble 5W, below is the demo video.

  • Louder version is here

    andriy.malyshenko • 04/18/2024 at 12:37 • 0 comments

    The project started with a line-level PCM5102 DAC which is very common among both Raspberry and Arduino users. I'm using it in combination with a classic 80's amplifier to get the look that I like and am used to with modern streaming capabilities.

    Sure it is possible to use it directly with speakers, I have just the DAC for it. It is TAS5805M that I used in the Louder Esparagus board. It requires around 20V of input voltage, so I opted for PD-enabled USB-C power sources. They are easy to find these days and 65W ones are just right wattage too. 

    I did some work collecting code and information around this DAC (it will not work out-of-the-box unfortunately). Instruction on how to set it up is available here, and frankly, it takes just a few minutes to get it working.

    Hope that many of the Raspberry Pi owners will find this little box useful.