Dreamwhisper

Discussion in 'Buyer and Seller Feedback (Negative)' started by Mr.Sneis, Mar 27, 2017.

  1. Mr.Sneis

    Mr.Sneis Friend

    Pyrate
    Joined:
    Oct 2, 2015
    Likes Received:
    1,321
    Trophy Points:
    93
    Location:
    Phoenix, AZ
    Without knowing exactly, the gist of the conversations suggests it was due to something in the digital board; I am guessing there were many parts eventually swapped and tested in the process. The PMD200 and many chips are SMD as I recall.

    Pretty stoked!
     
  2. Cspirou

    Cspirou They call me Sparky

    Pyrate
    Joined:
    Sep 27, 2015
    Likes Received:
    8,200
    Trophy Points:
    113
    Location:
    Northwest France
    That's lucky that they managed to replace the PMD200. I was looking around the other day for one out of curiosity and it's basically unobtanium. If I wanted one I would need to buy the cheapest gear that had one and desolder it.
     
  3. Cspirou

    Cspirou They call me Sparky

    Pyrate
    Joined:
    Sep 27, 2015
    Likes Received:
    8,200
    Trophy Points:
    113
    Location:
    Northwest France
    So I inherited this DAC from @Mr.Sneis as a white elephant project. The good thing is that this a modular DAC with power supply, digital filtering and DAC/Analog output on separate boards. I'll probably end up making a separate thread on the work I am doing to this, but I wanted to show some close up pics of the pmd200 chip first.

    As you can see the PCB around pins 100-95 is totally destroyed, but it's actually not as bad as you might think. Checking the datasheet most of these are NC (no connection). However pin 95 does serve an important function which is why there it a blob of solder to makeup for the damaged pad. More concerning though is that the alignment is terrible and I might have found a short circuit somewhere. There is also flux everywhere.

    So first thing for me to do would be to remove the pmd200 and take a close look at the PCB. If it is beyond hope then I'll need to remove the digital board and replace it with and I2S converter for the pcm1704 chips. Luckily this is exactly what df1704 chips are made for and they are still available. However I will need to create my own board.

    An alternative solution is an interesting project on diyaudio by a fellow named iancanada. He has developed some I2S boards that will make this into a NOS DAC. While it is not a true Assemblage 3.1, at least it will be functional.
     

    Attached Files:

    Last edited: Jul 25, 2018

Share This Page