Some background on the USB receivers

Input = Output

Actually there are many solutions on the market, but I decided to pick only 4:

• The HiFace module (based on the M2Tech)
• Rockna Audio, similar with HiFace, but simpler design
• The Musiland Monitor 03
• The WaveIO Module (from Lucian Luckit) link to his Site

Long story short, you listen to a few soundtracks and things are so clear, the WaveIO wins easily. Sound stage is more transparent, you can look through easier. Also texture of voices and instruments are more natural. On top, when you use a high end 5V power supply (instead of USB bus powered mode) all this improves another clear step.

You will read more about this in the Power Supplies and Sound Check sections.

The WaveIO USB Interface Lucian did a great job designing this receiver and we agreed he would make a special version for the DDDAC. No big things, but we left out the spdif for example and some other things you do not need when you build my design. On top, the drivers and ID's are recognized as DDDAC. So it is more consistent in your audio player. I am very glad I found this solution and many thanks go to Rumania!!! PS: what I like, is the fact the board can be easily switched between bus powered and external powered. Great for initial testing :-). Also both options have on board filtering! Download USB drivers: DDDAC Windows drivers for the WaveIO USB Module. Very easy install (XP, Vista, W7)

XMos design at its best: Lucian really did a great job designing this USB Interface.

Below is important information on the functioning and connections of the board (with thanks to Lucian):

• For the J8 (the one in top-left corner of the card - near the USB-B on-board connector): EXT means that USB data bus will be connected to the J1 external USB pin header while BRD option will choose the on-board USB input. If there's no jumper then BRD is selected by default.
  The J1 pinout is visible on the card:
  SHD = USB shield,
  GND = USB Ground,
  DT+ and DT- are USB Data lines,
  +5V = USB 5V VDD.
  
  
• uBNC (non-isolated) I2S Lines have self-explanatory comments on the TOP Silk Screen layer.
  
  
• J12 header (PSU Select - see bottom of the card) switches between two power supply options:
  EXT = external PSU by means of J13 power connector while USB = power from USB bus.
  Note: external PSU voltage must be 5V DC +/-10% @ 0.5 A or more, check the polarity right below the J13 screw-type connector!
  Even if there's a protection diode (D2) installed on the card, it wasn't tested when external AC voltage is applied thus please avoid this situation!
  
  
• J9 Pinheader is to control the LEDs for following signals:
  • L1 = 44.1 KHz
  • L2 = 48 KHz
  • L3 = 88.2 KHz
  • L4 = 96 KHz
  • L5 = 176.4 KHz
  • L6 = 192 KHz
  • L7 = Host Active
  • L8 = Audio Streaming
  • Host Active is ON when the card is plugged into the USB port and is recognized.
  • Audio Streaming is enabled when there's streaming over USB (when a track will play) and disabled else wise. Also, when incoming sample rate is changed, the Audio Streaming signal is disabled for ~1 sec. This signal could be used to MUTE the analog output if required (not done in DDDAC) Use normal LEDs (that can sink 8mA or less to lit).
  
  
• J6 Header is for isolated I2S output signals (used in the DDDAC) The NVE's IL715 isolator accept 5V or 3.3V power supply on the V+ pin to work accordingly (please see the bottom of the card). DT = I2S Data, LR = I2S Word Clock, BC = I2S Bit Clock, MC = I2S Master Clock (not used in DDDAC). There are also 5 pins dedicated to isolated GND. These are used too.
  Attention: There will be NO signals at J5 pin-header connector (Isolated I2S Outputs) if there's no voltage applied on the V+ and Isolated-GND pins (usually 3.3V but 5V is also accepted - please see IL715 datasheet for more informations).
  

On your PC, (in Program Files) you will find an application named "TUSBAudio Control Panel" When your DDDAC is connected to the USB port (and powered up) this application will allow you to change the ASIO buffer size and USB connection mode: Safe, Low latency.. and so on. I have not been able to do extensive testing, but it is worth trying around

NEW: after an update to firmware version 333 (use the TUSB program for this), the WaveIO can do up to 384 kHz sample rate. To indicate this. Lucian decided to use the 88.2 AND 176.4 to indicate 352.8 kHz and consequently the 96 AND 192 to indicate 384 kHz..

NEW!! have a look at the "other projects"

I made a nice project out of an Arduino controller and a standard 16x2 LC display to use this indication for more explicit messages :-)
"Other projects" page with the LCD project

Bottom Side Not much to say actually, just wanted to show this side of the medal as well :-) Related to the SPDIF outputs: On the DDDAC version they were left out as there is no need for them. In addition, H1, H2 and H3 mounting holes are NOT connected to the ground planes while H4 is... so, be careful! H4 must not be connected to the rest of the DAC Ground And, as a last note, just make sure that your WaveIO is powered properly using a 5Vdc PSU sourcing with approximately 0.5A. If you'll use the USB ports then it's possible that some laptop/motherboard USB power chips doesn't supply the required amount of current (specified in USB specs) Especially at higher sample rates this might affect proper functioning. Download USB drivers: DDDAC Windows drivers for the WaveIO USB Module. Very easy install (XP, Vista, W7)

Bottom view: Nice piece of handicraft...

Keep reading ...... the story continuous with the new S/PDIF functionality and new mainboard functionality and new mainboard new S/PDIF mainboard