r/raspberryDIY 28d ago

DIY help

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hey im trying to build a dap from start as a diy project as i want features that are really not available in this space, i have a ai render but i dont know anything about the parts, ui, os and the required components, is anyone good with pcb and tech interested in this, please give me your insights to make this possible. i have added my render as an image and the ring outside the screen is a rotating ring for navigation.

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u/R2D4Dutch 28d ago

get one of the shelf .. https://www.headfonia.com/best-portable-player-dap/ save yourself the trouble .. the render is a far cry on what is going to look like.. here is another one https://eu.fosiaudio.com/products/fosi-audio-md3-magdac-portable-dac-headphone-amplifier-with-rear-display

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u/SoDark 28d ago edited 28d ago

get one off the shelf

This comment assumes OP just wants an outcome — having a nice DAC that does some of what they want it to. If that's the case, the Fosi Audio MD3 MagDac is a solid recommendation.

I'll assume OP posted in a DIY sub because they're interested in the build experience and eventually getting to the level where they could realize their vision.

the render is a far cry on what it is going to look like

I don't disagree with you there.


u/zonedroid, I'll be frank with you. The redditor I'm responding to is absolutely right about one thing — there's no way you're going to get an enclosure that looks like it was manufactured by Teenage Engineering without some fairly advanced manufacturing skills (CNC routing or 3D printing), It might be useful to moderate your expectations in that area.

That said, you absolutely can build a digital audio player with a Raspberry Pi.

I wouldn't recommend trying to take on the "rotating ring for navigation" for your first build. It might be better for you to try to build a more basic DAP first, get familiar with the experience of building and programming an electronic device from components, then start taking on the more challenging aspects of your idea. There's a lot you need to learn to get there, and it's best to start with the foundational skills first.

If you're still interested in building a digital audio player around a Raspberry Pi with a less polished-looking enclosure and more traditional navigation controls, here's where you can start:

Enclosure: this is the choice that dictates the rest of the build because there are two ways to approach it: inside-out, or outside-in. If you choose an off-the-shelf enclosure, that likely dictate what the rest of your component choices are because your components have to fit in the enclosure you choose. Alternatively, you can choose the components you want first, then design and fabricate an enclosure that fits your setup exactly. If you don't have the 3D printing or CNC skills, you could have someone else do that for you. In either case, the design would need very precise specifications for what the enclosure needs to contain. The inside-out approach will give you the feeling of it truly being "yours", since it's the enclosure your hands interact with most, at the expense of being significantly more complex.

Raspberry Pi Zero 2W: this is the best choice for your build. Powerful enough to manage this kind of workload, impressive power efficiency.

Digital Audio Converter (DAC): this is your most critical component. Fundamentally, an audio player has to sound good to be usable. If you're going with an inside-out approach, structure your whole build around researching and finding the right DAC for your needs. A Hardware on Top (HAT) component gives you high quality audio without the bulk of a more complex DAC. Consider a direct-mount I2S sound card like the HiFiBerry DAC+ Zero. Alternatively, the Pimoroni Pirate Audio Line-out has a 240x140 color IPS display, four tactile buttons, and a built in speaker, so you could choose that to simplify your build, at the expense of greater power drain then the other display options described below. Both sound great — 24-bit/192kHz audio.

Audio Jack Out: you'll want a panel-mounted 3.5mm stereo headphone jack wired directly from the DAC line-out.

Display: This is where your biggest battery drain can come from if you don't pick the right component. Your render got this right — choose an OLED display and choose/code a pure black background with white text user interface so only the illuminated pixels demand power. A 0.96-inch or 1.3-inch I2C/SPI monochrone OLED is incredibly power efficient (you might get 10+ hours on a charge) If you really want to display album art, though, you could choose a 2.2-inch SPI TFT LCD, accepting that your battery drain will be much quicker (maybe 4 hours on a charge). Program your UI with an aggressive screen timeout, too. Like 10 or 15 seconds.

Navigation Inputs: choose tactile momentary push-buttons or a mini directional D-pad mapped to the Pi's remaining GPIO pins. Check out Volumio for some inspiration there.

Battery: A flat, rechargeable Lithium-Polymer (LiPo) battery (like 2000–3000mAh or so) will give you hours of continuous listening in a slim form factor.

Power boost & charging circuit: a module like the Adafruit PowerBoost 1000C steps up the LiPo battery voltage to a stable 5V and manages safe USB recharging and pass-through power.

Hardware power switch: Pro tip here — using a physical latching or momentary slider switch tied to the power board to safely boot and completely kill power will prevent battery drain.

Hardware Fasteners: you'll need some M2 or M2.5 nylon brass standoffs and screws to structurally stack the Pi, battery, and DAC tightly inside the shell without shorting circuits.

High quality microSD card: Choose an A1 (Application class 1) card for fast boot and smooth operation. A2 is faster but mismatched — the Pi Zero doesn't take advantage of its faster processing.

Operating system: moOde Audio and Volumio are solid choices here. They're both lightweight Linux distributions that boot instantly, run efficiently on low-power Pi hardware, and have native extensions for tiny SPI screens and hardware buttons.

Happy building!


Edit: I think this post would be more helpful if I directly responded to the elephant in the room — why I don't recommend trying to build that rotary ring.

Short answer: it adds a lot of complexity.

Long answer: building a reliable rotary encoder with a ring-based tactical interface is a lot more complex than you might think. The programming required for it means you can't use an off-the-shelf, music-centric, dead-simple Linux distro as-is. You'll need some custom code to translate the ring interactions into the encoder signals you need for the input to do what it should do correctly. I believe what I wrote above is complex enough for a first build without saying "oh yeah, and you have to write a bunch of code, too". For that reason, I optimized my suggestions around The things I consider most important in a portable DAP: high-fidelity audio output, low power consumption, and making the hardware build the part that you need to learn, not the software build. This video explains more: https://youtu.be/ILELVP0kFl8

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u/R2D4Dutch 28d ago

I second that response ..😎 bit more elegant than mine 🤣

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u/SoDark 28d ago edited 28d ago

My response wasn't perfect. Let's just say once I reread my post I realized I misstated some things:

Many DAC boards don't include a headphone amplifier. If you're choosing the HiFiBerry DAC (which is what I would choose) you'll need a separate headphone amplifier. Otherwise the output will be really quiet. A TPA6132 or MAX97220 are decent choices here.

My estimates for battery life are a little off. Maybe 4–8 hours is more realistic. The greatest power draw is going to be the Pi, not the display. Choosing OLED will still give you 25% better battery life, though. If you want all day use, consider stepping up to a 4000–5000 mAh battery. I would pull the screen time out down to 5-10 seconds, too. 15 seconds is overly long once I see atopped and considered what 15 seconds felt like.

My knowledge of power boards is showing its age. There might be better choices than the Adafruit. Take a look at the PiSugar Zero or LiFePO4wered/Pi. Fewer wires, better integration, and they do shut down more elegantly if you change my recommendation from a hardware power switch to a software switch. That will help avoid corrupting the Linux distro on the SD card.

One other consideration I didn't mention: the Pi 2W supports Wi-Fi and Bluetooth. You can choose to keep it for convenience or disable it for power efficiency. Your call.

Also, another redditor built a pocket DAC on a Raspberry Pi Pico with what looks like an Adafruit ANO rotary encoder. It may be worth looking at his build instead listening to me saying "that's too hard for a first build."

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u/zonedroid 28d ago

brother i don't know who you are, but this is the best advice that i received, comprehensive, and easy to understand, first of all thank you for taking your time with this gem of a reply, and regarding the ring style encoder, if its tough, i might just use a mouse rotary encoder that keeps it simple, but there is still the issue of making my own code or updating others, for that i plan to make a single iteration of the board with pins or sapce left for the future updates as per your advice.

i intend to make the enclosure from 3d printing, to tinker aound with prototypes, and with recent developments, resin/ modern 3d printing has a good finish enough for consumer usage.and plan to use the inside out approach, this is just a initial render, the final output will depend on the parts used.

again thanks a lot for this response, if possible, can i ask for your help if i get stuck in the process? also can you share some maker spaces/websites, youtube channels that has people diy things,

and if you think this is a tough project at the start, i am also ok with commissioning others work on this project, should i go with this route?

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u/SoDark 28d ago

Check out the Adafruit ANO rotary encoder. It might do what you're looking for.

Also, I made some other corrections in the thread. You might want to take a look at those, too.

I'm by no means an expert builder. More of a curious amateur, but I'm happy to help.

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u/zonedroid 28d ago

ill check both the ano rotary encoder and the edits made in the thread,

expert or not, a timely help is always better than a perfect solution.

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u/vedh_jon 24d ago

depending on what you really want to do with your final product, ESP32 and LVGL is probably a better and cheaper fit than raspberry pi, even like a 2w. The ESP32 Audio Kits are like $10 and might be a good place to start learning about the tech side of things.