Raspberry Pi I2S to SPDIF Hat

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

  1. noise11

    noise11 Rando

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    Hey scott did you tried feeding each board with a different LPS?
     
  2. strangecargo

    strangecargo Acquaintance

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    @Michael Kelly I noticed that there are pictures of a case for the 502DAC board up on the pi2design site. Any idea of an ETA for when we'd be able to buy them?
     
  3. Em84

    Em84 Rando

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    Just received my 502DAC with case.

    I may be one of the last people on the planet that prefers using Toslink.

    Michael, thanks for including a Toslink port that doesn't include a door that scratches the nice polished end of my Lifatec glass toslink cable! :) It's the little things.

    I have 2 x Uptone LPS-1's so I figured I'd use each to power the Pi and 502DAC boards separately (overkill)

    So if I have it correctly, the Toslink output of the 502DAC is directly powered by the ultra noise Uptone LPS-1 at 5V, and the very nice LT3042 powers the NDK oscilators to help reduce jitter as much as possible.

    After that I leave it to the glass Lifatec toslink cable and my DirectStream DAC's FPGA to work it's magic with jitter reduction and D to A conversion.

    It sounds better than the Digi+ Pro it replaced. I don't think I've had a better Toslink source in my system.

    I'm running DietPi and using this 502DAC as a Roon endpoint.

    I just used the same Pi board and SD card that was used with my Digi+ Pro, and went into DietPi to change the audio hat to Dac+ Pro and it worked right away. Really easy.

    The only issue I ran into is I can't use my nice right angled Oyaide 2.5mm connector to power the 502DAC board - the case prevents proper contact/insertion so it needs a straight 2.5mm DC plug but not a major issue at all.

    Thanks for the great HAT Michael and thanks for keeping quality Toslink sources alive !

    A metal case would be really cool, at some point later, but I don't mind the see through look at the moment.

    Looking forward to the DAC3 for a second system also.

    Photos here:

    http://imgur.com/a/hD3qL
     
    Last edited: Aug 3, 2017
  4. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    Cases for the 502DAC are now ready to ship. Sorry for the delay, we ended up waiting on the standoffs! Anyway, they are in the store at:

    http://www.pi2design.com/store/p16/502DAC_Acrylic_case.html

    Use coupon code SBAF at checkout and the cost is $0 plus shipping. Thanks for all your patience.

    BTW, you can use the coupon code if you are ordering a 502DAC also, or just the 502DAC alone. It takes $10 off your total purchase.

    Cheers,
    Michael
     
  5. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    Thanks for the very informative write up. So glad you're happy!

    Would you be willing to test it with a standard Pi power supply? Anyway you could do it as a blind test? I am really curious to see how well the 502DAC does with a stock supply versus a very high end power supply.

    Cheers,
    Michael
     
  6. Xen

    Xen Friend

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    Whoa, for just the cost of shipping? That is truly an awesome deal! Thanks so much!
     
  7. Em84

    Em84 Rando

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    Hey Michael. Yes happy to try this.

    in this case with using the stock Pi PSU, the Toslink connector is powered by the 5V stock Pi PSU? But the NDK oscillators will still be powered by the very nice ultra low noise LT3042, if I understand things correctly?
     
  8. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    Calling for reviwer
    Yes, you are correct. The toslink connector is powered from the raspberry pi 5V rail, but there is a ferrite bead in the line.

    I greatly appreciate your willingness to do this. That's why I love this forum, you guys (and gals) have been great.

    Cheers,
    Michael
     
  9. Em84

    Em84 Rando

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    Not a problem Michael. I'll be away for a few days but definitely looking forward to trying this out later in the week and will report back.

    Cheers
     
    Last edited: Aug 6, 2017
  10. Em84

    Em84 Rando

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    Just a question on this Michael. Is the ferrite bead on the Pi board or your 502DAC board? And what's it's purpose/s ? RF filtering?

    Cheers
     
  11. pandather

    pandather Acquaintance

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    I just finished setting up my rpi with the newer revision board and an lps I made. (and moode w/ bubbleupnp server so I can use Tidal) (btw the high pitched (coil?) whine is completely fixed.) Will post impressions after a few days of listening or so. The sound is awesome though, it seems to be a bit more dynamic than usb into my Modi Multibit.
     
  12. Merrick

    Merrick A lidless ear

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    I switched back from Moode to Volumio due to Moode failing to complete a library scan and also shutting off at random, and I was pleasantly surprised to see that the 502DAC is listed as an I2S DAC in the settings, no need to make Volumio think you're using a Hifiberry.
     
  13. pandather

    pandather Acquaintance

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    Wow that's actually really nice. I think I'll switch over. I dropped the $10 they started charging for Mo0de because it was what I used before and I wanted to support the dev, but I also like free software. I haven't had any issues yet, but I guess I'll just use another sd card and pick the one I prefer. Also, just for future reference, does anyone have the details for the power connector? (I saw it once but the last 3 times I looked [even using search,] I couldn't find it) I just kind of hacked it together with an old wallwart I found that fit, and soldered the cable onto the lps, but it'd be nice to make an enclosure for the lps with a removable cable.

    Thanks!
     
  14. Merrick

    Merrick A lidless ear

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    I also paid the $10 for Moode and I think it's good software, but I was having issues and didn't want to bother doing detailed troubleshooting.
     
  15. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    The power jack accepts 2.5mm center positive with a 5.5mm length barrel. The case does cut into the depth a bit, but as others have found out a typical straight plug works fine.

    Cheers,
    Michael
     
  16. Michael Kelly

    Michael Kelly MOT: Pi 2 Design

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    Sorry I forgot to answer this. The bead is from the PI 5V rail to the rest of the 502DAC. It is mostly for RF, but does server to decouple the rails which helps overall noise.

    Again, can't to hear your impressions with just the standard PI supply. :)

    Cheers,
    Michael
     
  17. Em84

    Em84 Rando

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    Thanks Michael. I'm looking forward to testing this out myself over the next few days.

    Since I'm using Toslink, obviously there's no electrical noise going from the 502DAC to my DAC.

    So it will be interesting to hear if powering the LT3042 (which powers the NDK's) with cleaner power makes an audible difference. And if powering the Toslink connector with cleaner power also makes an audible difference.

    Later I will try the other digital outputs of the 502DAC but Toslink is really my preferred so testing the other outputs will be later, on a quiet weekend perhaps.
     
  18. damaged-goods

    damaged-goods Acquaintance

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    I've compared the Pi supply vs my "over the top" version (ifi ipower into pi and sbooster psu into the 502dac).
    Listened with Meier Corda Daccord - Schiit valhalla 2 - HD650.
    In my regular setup I power the complete transport through the 502dac's barrel jack using just the sbooster, without the ipower.

    The "OTT" version has a more holographic soundstage, more space and air around the instruments, smoother treble, sounds more focused and more "real". It's hard to decide how big the differences are, they are not major, but I prefer the low noise psu version as it shows the magic of the Val2 can do.
    It does sound very good with the Pi psu already, better then the Hifiberry Digi+ I used previoulsy.

    It will be interesting to see how the 502dac compares to the Schiit Eitr.
     
  19. Em84

    Em84 Rando

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    Hi, just out of interest, which output of the 502DAC are you using?
     
  20. damaged-goods

    damaged-goods Acquaintance

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    Sorry I forgot to mention this. SPDIF from the BNC with a RCA adapter.
     

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