Raspberry Pi I2S to SPDIF Hat

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by Michael Kelly, Apr 30, 2016.

  1. Azteca

    Azteca Friend

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    I don't want to derail, but can you briefly outline the advantage behind this?
     
  2. pandather

    pandather Acquaintance

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  3. darkstar>eyesoftheworld

    darkstar>eyesoftheworld New

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    I'm very interested in this SPD2. Right now I use lap top>chi-fi USB cable>regen>USB adapter> yulong u18 USB/spdif>yulong d18 DAC. This is pretty much all I've ever known as a source. After reading the USB converter threads on another forum (I'm sure some of you know which one I'm referring to) I was set to buy the singxer su-1. I some how Stumbled on the raspberry pi and the digi+. Through trying to read everything I can I stumbled upon this thread. My main question is, would a raspberry pi with the SPD2 be a better choice than one of the new USB converters out there?
     
  4. error

    error Friend

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    Someone has to try that before we know...
     
  5. error

    error Friend

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    I'm also curious if advanced DIGI HATS (Hifiberry Digi+ Pro, SPD2 and maybe others) would benefit from better i2s or not...maybe @Michael Kelly can comment on this.
     
  6. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    The big issue with the raspberry pie sound output is the clock jitter. When you provide the clock externally, which is what our hat and those others do as well, you significantly reduce the clock jitter.

    External FPGA or other re-clocking devices will not improve upon our hat. Essentially, we are a re-clocker.

    Cheers,
    Michael
     
  7. bobsherman

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    Any update on availability?

    thanks
    Bob
     
  8. Vastx

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    Meanwhile, waiting for the release of the new version of the speed2, I packed up my Pi, the speed2 and the diyink psu in a metal case. Nothing fancy, I was just tired of all the wires around in my living room :)
    [​IMG]
     
  9. Xen

    Xen Friend

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    Random left over case from another project or something more specific?
     
  10. Wfojas

    Wfojas Friend

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    Add in a display, and you're in Bryston territory. Very nice, have you settled on a LPS setup?
     
  11. pedalhead

    pedalhead Friend

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    ... Except, I think you're gonna need a bigger chassis to cope with that toroidal ;-)
     
  12. Vastx

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    The case has been specifically bought... for another project :) But I didn't go on with it so I recycled it for the raspy.

    Man... It lacks a display but I am way beyond Bryston territory! It has a LPS onboard. Bryston Pi comes with a smps and charges you more money for a LPS. So I would say screw the display :p I wanna keep it cheap and good sounding.
    Edit: I settled on the diyink lt3042. But with speed2 I could have spent a lot less. Almost pointless in here but I already bought it for the digi+, what a waste of money.

    Yep, It is pretty tight in there, I agree. But I can put the top cover and close it even if it the toroidal touches the top cover. So I'd say It will be alright.

    The first advise I can give is buy a bigger case (mine is 220x150x80).
    The second is buy an insulated BNC panel connector. Otherwise you will waste the transformer isolation. I didn't thought of it and now I have to buy another BNC or use a RCA. XLR is already isolated on the 3rd pin.
     
    Last edited: Oct 2, 2016
  13. minio

    minio New

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    Hello, I'm a new user and i just discovered this interesting project. Count me in for purchase, I'm from Italy.
     
  14. nedifer

    nedifer Facebook Friend

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    I would also be very interested in one of these. Would it be possible to turn one into either a Roon Bridge or a Squeezelite streamer? I wouldn't need an image with either of those, but knowing how to apply the ALSA changes to take advantage of the clocks would be useful.
     
  15. fierce_freak

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    I'll definitely grab one. Looks like it's time to research up on how to make a ridiculous rpi digital source. I'll read through the whole thread, but I appreciate if anyone can provide the highlights (number/type of powersupplies, screens, anything else).
     
  16. evikins

    evikins New

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    @Michael Kelly
    How is the your progress and pre - order time ?
    Thank
     
    Last edited: Oct 19, 2016
  17. Scott Kramer

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    @Michael Kelly, could you please post the speed2 schematics (or current design) --> those PDF's are missing now--
     
  18. nedifer

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  19. Scott Kramer

    Scott Kramer Friend

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    Yes, sort of... they glommed on a DAC to it now however :( edit: Looks good tho after checking the layout, the wm8804 is slaved to the good clocks.
     
    Last edited: Dec 13, 2016
  20. Naimsayer

    Naimsayer New

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    Well the dac chip itself is only a $2 part, so this seems to me like a very smart idea - a single pcb can now be used for digital only, analog only or digital and analog versions combined. If I understand correctly, fitting the dac chip also helps ensure driver compatibility with Hifiberry Dac boards even if you are only looking for digital out. This looks like a very useful board indeed.
     

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