Using SMSL M400 to fully decode MQA

Hi all,
Trying out Roon. I have a bluesound node 2i as end point and an SMSL M400 handling MQA. Do these pics of the display on my SMSL and a screen shot of the Roon signal path indicate that I am using the SMSL M400 to fully decode the MQA file streaming from Tidal?

You cant get pass MQA out via Spdif of the Node2i into the SMSL. So the path is correct just the DAC only accepts MQA via USB input. Looks like the Node2i is doing the full decoding your just getting the output of that stream to the DAC either already decoded or it’s an undecoded stream I would say the latter. Roons has no idea what output your using after the Node2i so it’s reporting what it knows the Node is doing and nothing more.

To see if the Node2i is sending out fully decoded or undecoded material you need to try an MQA file that has a higher res master output as that one is only 44.1 so hard to tell. But I would imagine it’s either first unfold or just untouched. Neither of which will help for the SMSL DAC.

Thanks Simon,

Okay, it looks like if I get Roon to do the decoding and the node to do the rendering, I get a Hi-Rez 96kHz indicator on the SMSL but no MQA symbol, Will the SMSL do both the decoding and rendering if I can get it to pass through the node 2i, and will using the optical output on the node 2i allow me to do this?

Hello @Nigel_Potter,

The Bluesound NODE 2i is capable of passing MQA over its SPDIF outputs.

The NODE 2i has an option for “External MQA DAC” in the BluOS audio settings. Here’s how it affects playback when the NODE 2i receives and MQA stream:

“External MQA DAC” = Disabled: SPDIF outputs an “MQA Core Decoded” stream in a 24/88.2 or 24/96 container.

External MQA DAC = Enabled: SPDIF outputs a bit-perfect undecided MQA stream in a 24/44.1 or 24/48 container.

Something to consider is wether the SMSL M400 handles MQA over it’s SPDIF inputs. Many DACs are only capable of decoding/rendering MQA on their USB or Network inputs. We do not have the M400 in-house for testing, so you will need to confirm this with the manufacturer.


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No as said this DAC only accepts MQA via it’s usb input it will ignore MQA encoding via Spdif and just treat it as standard PCM so want your getting is Roons first unfold to 96/24 but you won’t get the 2nd MQA decode and filters. If you want full MQA via that DAC ditch that Node2i and get a USB endpoint or ditch the DAC and use the nodes output.

Hi, I am using M400 too, SMSL M400 handles MQA over its USB only.