Compatible I2S source devices


Success!!! :slight_smile:

I have just prepared the other GD-Audio module, using their original female pin connector (with removed mclk cable) and also gnd removed and soldered directly to one of Hecate GND pins. Now it works correctlywith all formats and both channels :slight_smile: even dsd128 works like charm.

I guess the cables i used on previous board for i2s have been flaky.

Its working even in no box and it’s sitting near linear psu with metal casing , now then listening test and search for good case can start :wink:

@@Patrick many thanks again, i was close to abandon this project after first failures, now i am very happy!! :slight_smile:


@ Maniac You’re welcome, can’t wait for your feedback 101_gif


@Patrick does it happen to you that HECATE stops responding on the USB until you power-cycle it? It happens to me with Ropieee and also DietPi (using RoonBridge) from time to time. It happens when skipping to next track - new track starts as a strong noise for 1-2 seconds and then Hecate stops responding. In the logs i can see lot of issues with USB when this happens:

Jan 16 09:21:13 DietPi kernel: usb 1-1.2: 1:2: usb_set_interface failed (-71)

in RAATServer logs:

01/16 06:42:00 Trace: [RAAT::TREXO] [lua@0x71e0443c] [] GOT [252] {“request”:“setup”,“format”:{“sample_type”:“pcm”,“sample_rate”:44100,“bits_per_sample”:16,“channels”:2,“sample_subtype”:“none”}}
01/16 06:42:00 Trace: [RAAT::TREXO] alsa output setup: format is pcm 44100/16/2
01/16 06:42:00 Trace: [RAAT::TREXO] opening [hw:CARD=TREXO,DEV=0] 44100/16/2
01/16 06:42:00 Trace: [RAAT::TREXO] prefer larger samples = 0
01/16 06:42:00 Trace: [RAAT::TREXO] [ALSA] [hw:CARD=TREXO,DEV=0] using hw pcmformat S16_LE bitspersample 16
01/16 06:42:00 Trace: [RAAT::TREXO] [ALSA] [hw:CARD=TREXO,DEV=0] Requesting 2 periods
01/16 06:42:00 Trace: [RAAT::TREXO] [ALSA] [hw:CARD=TREXO,DEV=0] Requesting 1764 frames/buffer (882 frames/period)
01/16 06:42:00 Trace: [RAAT::TREXO] [ALSA] [hw:CARD=TREXO,DEV=0] Initialized with 2 periods with 882 frames/period and 1764 frames/buffer
01/16 06:42:00 Error: [RAAT::TREXO] error in snd_pcm_hw_params: Input/output error (-5)
01/16 06:42:00 Warn: [RAAT::TREXO] [lua@0x71e0443c] [] setup failed: RAAT__OUTPUT_PLUGIN_STATUS_FORMAT_NOT_SUPPORTED

EDIT: i was suspecting the 5V regulator fed by 5,24V from linear PSU could get under-voltage so I have tried powering Hecate USB directly (without using regulator) from RPI USB port but it happens there too.

Then in regards to SQ - i think it’s on the same level when comparing Roon , but still Bridge2 is on top when playing UpNP.

I plan to test UpNP also via Hecate and yet still the Hecate has to go in the shielded case (it’s still without any case) - this might change the situation yet.


Hi Maniac, I never had such issue with my RPI3 neither with the NanoPI Neo. I’m using DietPI and I tried Roopiee (exclusively on RPI) but not for a while.

I guess the pb is there whatever the output is (SPDIF or I2S)?

Good idea to test another software than Roon bridge, however I always found Roon bridge as very stable and able to detect the USB correctly.

Hope you’ll find the pb.


I wanted to try mpd + upmpdcli apps instead of RoonBridge , however it seems DietPi does not have multicast configured in the kernel so i switched to SD card with Ropieee. Installed it sucesfully yesterday’s night, but did not have chance to listen (i am also hoping for better SQ than Roon) and to see if the problem would reoccur.

Will let you know the results hopefully soon :slight_smile:


Interesting development for Oppo owners…

(Look for 3rd link down, near the bottom of page)

Ive been modding my Oppo 203 and have fitted this guys linear power supply to my unit, to great improvement. His work is top class and when he brings out his I2s board I’ll be fitting it to my player.

The Oppo is a Roon Endpoint and if I can feed I2s from kit Imalready own directly to my Directstream then wow…I’m in!


Hi, I recently installed a Matrix X-SPDIF 2 between my Melco and DirectStream as follows: Melco > USB > Matrix > HDMI > DS.

The Matrix worked right out of the box, with and without an external PSU (in this case, an iFi iPower 5V).

I configured the Melco and Matrix to stream native DSD and my DS is showing “DSD” instead of “DOP” when playing DSF files, so I guess native DSD is working.

Preliminary impressions are quite positive – detail and sound stage/image focus have improved, without any noticeable negative effects.

Anyone else using a Matrix with their DS? If so, any suggestions as to the preferred Matrix dip switch settings for “IIS Reverse” and “MCLK”? Thanks.

Matrix X-SPDIF 2
Snowmass DirectStream Sr. upgrade - Available in the Downloads Section

@Bootzilla I also have the Matrix in use. I think the X-SPDIF 2 is PS Audio compatible by default. MCLK you would need with the Matrix X-Sabre Pro DAC. In Sync-Mode the X-SPDIF 2 will be the Master then.

With DSD-playback, when the LED is white then you have native DSD. A blue LED means DoP and green stands for PCM.

At the moment I have the X-SPDIF 2 between the USBridge from Allo and the DS DAC. As PSU I use the adjustable output of my HDPLEX set to 9V. I’m still thinking of the X-Sabre Pro as a second DAC.


@Bootzilla Interesting to see that the SQ can be improved by an XMOS/XILINK interface (Matrix is similar to Xsinger or Hecate devices) on a streamer like Melco designed with extreme care, especially if we compare it with several SBC cited here (RPI, NanoPI and others standard computers). The Melco is far beyond.

This reinforces the idea that bypassing the integrated XMOS (USB input) of the DS Dac is a good idea. Did you test the SPDIF output instead of the I2S. Is it still better than the USB link (Meco direct to DS Dac) ?

Holzohr said

With DSD-playback, when the LED is white then you have native DSD. A blue LED means DoP and green stands for PCM.

Hi @Holzohr, and thanks for the post, good to know there is another Matrix/DirectStream user out there. When I play DSF files (1xDSD and 2xDSD) on my Melco, the Matrix light is BLUE, but the DS display now registers "DSD" instead of the former "DOP," so I am not sure what to make of that.

@Patrick: Hi, I have not yet tried the Matrix’s SPDIF output. I have an AES/EBU digital cable, and I intend to try it at some point between the Melco and the DS. Is there reason to think AES/EBU could be a better-sounding connection than I2S? Thanks.


It seems the Matrix is transcoding DoP to native DSD. From the Matrix X-SPDIF 2 website:

Configurable IIS Port

X-SPDIF 2 support different standard of IIS, it can compatible for different devices by configuring the IIS definition switch. The DoP converting function transcode DoP audio stream to native DSD stream output from IIS port.
The color of the LED stands for the input format.


Btw, I have to update my post from last September (bridge means the Matrix X-SPDIF 2 USB-to-I2S bridge):

I have tried the bridge directly with Roon ROCK and my old Daphile box but maybe the best way is to use it with a Raspberry Pi (via USB) and RoPieee (as a Roon endpoint). Thanks to Harry (the RoPieee author) the latest version supports DSD natively (even DSD512?). The current used kernels in ROCK and Daphile supports DoP only. At the moment I let Roon upsample everything to DSD128.
Daphile supports native DSD up to 512 via the Matrix X-SPDIF 2 for a couple of months and Roon has updated ROCK now, too.

So, native DSD512 is possible with:

  • Daphile
  • Roon ROCK
  • Raspberry Pi2/3 with RoPieee
  • Allo USBridge with DietPi


@Bootzilla No idea at all but in I2S I believe (may be I’m wrong) that it is the preferable input on DS Dac as it supports native DSD and up to DSD128. On Hecate the SPDIF (coax) output beats the a RPI3’s USB output connected directly to the DS. A RPI3 is not on par with a Melco so…


short update about Hecate with AugioGD i2s hdmi output - it was playing stable for the last week (kept Roon playing 24x7) - so far so good :slight_smile:

now i am working with my father on the copper enclosure, hopefully 1 or 2 more weekends to have it finished

teaser photos:


Hi Maniac, realy impressed by your box 105_gif

I can say too, I have a very stable behaviour, since more than one month now, on the NanoPI side or the Hecate side.

One thing puzzled me on your pictures. How do you manage the different grounds ? If I see well the copper case seems to link all connectors ground?
Along my experience, with these setup we have to manage at least 3 or 4 different PSU:

- the SBC (RPI in your case) PSU => 5V

- the Hecate's input PSU through USB (which is the same as the SBC PSU in my own case in NanoPat) => 5V

- the Hecate's output PSU for the Xilink processor and the I2S+SPDIF outputs. This one is self powered (may be a weak point?) and isolated from the Hecate's input PSU.

- the I2S/HDMI LVDS output mudule's PSU => 3.3V

I took care to not ground them all together. Especially the input and output of the Hecate board are isolated, so I think it make sense to let things as they are. The HDMI module will be inevitably grounded with the Hecate Output, so we have no choice to link the 3,3V PSU ground with the internal output PSU ground of the Hecate. For that I choosed, a bit arbitrarly I must admit, to ground my metal box only to the HDMI output module PSU ground.

How do you manage your grounds and do you think that grounding all together does not harm anything ?


thanks Patrick :slight_smile:

You are right, I have to isolate all connectors from the case. I was also thinking about isolating also the HDMI connector and connecting only the RPI GND to the case - to have case grounded only via RPI PSU. I plan to use some kind of insulating pad/tape to do the isolation of connectors…

Ideally I would do it in a way that I can choose which PSU will provide the GND to enclosure so I can do some listening tests and choose the best one.

I agree that connecting grounds from 3 PSUs to the case could make trouble, i don’t know if it could be even dangerous for the electronic parts, but definitely it could incur noise to Hecate/I2S output module which I want to prevent.

I would need to have a look how is Hecate powering it’s SPDIF/I2S output part of the board as I have one 5V linear PSU still free, however I do not have spare 5V regulator. That may be good idea for some future project… :slight_smile:


Is there a pin-out diagram for the PS Audio I2S over HDMI standard which shows which dataline turns on and off the de-emphasis flag?


We openly share this standard we created with the rest of the world. It’s a great format and one we’d love to encourage other manufacturers to adopt. Here’s the pinout and schematic.


Thanks Paul. That answers half of my question. The other half is does one of these data-lines represent a flag for turning-on de-emphasis? In investigating Raspberry Pi I2S implementation I can find a documented data-line which does this. But in looking at this diagram, I can’t identify any similar data line which is documented here.

Am I missing something?


I can give you a little more info: the I2C control lines are used for signaling. What states and/or bit sequences do what I don’t know. You won’t hurt anything by trying a pull up or down to see if it does what you want, maybe 10k.