• 3 Posts
  • 14 Comments
Joined 3 years ago
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Cake day: June 9th, 2023

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  • You don’t need something huge. Remove the DVD drive and the old mechanical drive from a USFF machine, stick a pair of 4TB drives in it, and put a basic debian image on it. Configure SMB with a shared folder or two, and voila: you now have a comfortable NAS for maybe £20 plus drives. Add in a sata pcie card if you can find a decent low-profile one, and that’s an extra four or even six drives. It won’t give you the cream of top performance, but it will be perfectly serviceable for a homelab.





  • Neither. This is a purely personal project, and I’m using as much off-the-shelf as possible. The dac itself doesn’t have to be top of the line, just decent. The PCB itself I’ll probably just have printed, rather than trying to breadboard it or make some ungodly wire mess.

    Some stuff I can get for almost pennies, like a USB-C controller and the actual sockets and plugs, so this is a non-concern. The actual dac chip though, I’m expecting (or at least hoping) to find something around the £30-£40 mark, although this may well be aspirational. That said, this is something I can theoretically transplant to my next device, and the next after that, assuming I create custom housings for them.


  • I’ve put some thought into it, but realistically I lack the experience to flesh out the idea.

    I’ve seen a few small DAC concepts out there, like https://www.elektroda.com/rtvforum/topic4091483.html or that iPhone modification that Strange Parts did a few years ago, but none of these really 100% match my needs. As for the sizing, the only real answer I have for you is “small” - whilst it is intended for integration into a phone, I’m going to be building a housing for that phone from scratch, so the size requirements are somewhat led by the dac itself. I had a few ideas about using a flexi-strip in place of a solid PCB too, but I think that’s aiming too high for my non-existent skillset. Instead, I have no problem redesigning the board to be long and thin if necessary, or squat and fat in the alternate. Realistically, it’s probably going to be somewhat L-shaped, but there’s a good two inches or more of width and something like six inches of height to work with - minus the PCB of the phone, that is.

    The actual handset it will be accompanying is a Sony Xperia 1 IV, but that’s largely meaningless as we can add pretty much any additional size to it up to a reasonably large handset within the last ten years (preferably with an OLED display, but I’ll be somewhat limited in terms of compatibility anyway and might have to end up running the screen in an alternate fashion somehow, I haven’t thought too hard about that side of things because the project is useless if I can’t design a DAC inthe first place).

    The heatsink stuff was really just a suggestion, I’m not actually sure if it will be necessary, but it’s good to have the option.

    Specifications wise, it essentially needs to do four things:

    • Pass any connected headset microphone through to the handset
    • Run an EQ that is addressable and configurable from the handset
    • Have a volume ceiling at least comparable to a fifth-gen iPod video (i.e. a wolfson chip)
    • Take power from, and pass data and power through to, the existing USB-C socket on the handset.

    The bit that I’m stuck on, really, is the addressable EQ. I could possibly go with some sort of Arduino-esque solution, but that’s a lot of lifting for a single-purpose device. I have no idea where else to start looking - I know there are RISC chips out there that run on nothing but a button cell, but again I’m clueless as to whether or not this is a good idea.