Roon Nucleus+ configuration to allow the DAC to decode MQA, instead of Roon decoding

[Tushar_das]

Dear Team,

Can someone guide me on the configuration to allow the DAC decode the MQA instead of the Roon.

Below are my device (iFi iDSD) settings, the iFi iDSD is connected to my laptop via USB 3.0.

Thank You,
Tushar.

[Tushar_das]

Signal Path:-

[Martin_Webster]

Set the DAC to Decoder and Renderer and set Enable MQA Core Decoder to No. But note that you will not be able to use DSP and retain MQA signaling, i.e. use the Audeze presets and have an autenticated MQA signal.

[Tushar_das]

Thank you so very much… I now get what you meant, and able to understand the settings what they do.

[Carl]

@Martin_Webster

Set the DAC to Decoder and Renderer and set Enable MQA Core Decoder to No.

All that should be needed is “Set the DAC to Decoder and Renderer” … this way the Roon’s MQA decoder engaged should Roon’s DSP features be needed also be needed.

“Enable MQA Core Decoder to No” is a too much of a sledgehammer for my preferences.

[Tushar_das]

Dear Carl,

This is what I understood from what you just said, Please correct me if I’m wrong. Set the DAC to ‘Decoder and Renderer’ and Enable MQA Core Decoder to YES. The ROON will software decode MQA (max 96) to separate the MQA signature, apply DSP and then add back the MQA signature. Once the signal reaches the DAC it decodes the MQA (as we have Set the DAC to ‘Decoder and Renderer’), this way both the DSP & MQA is available… Is my understanding correct?

Regards,
Tushar.

[Carl]

Hi @Tushar_das,

Not quite … MQA decoding is only perform once, after that is about MQA rendering.

DSP processing can only be performed on the decoded MQA signal, however in order for it to still be MQA renderable the MQA signaling information must be preserved (it has to be extracted, the DSP applied and then re-injected into the signal) then the resultant signal can still be rendered by an MQA DAC.

In Roon with the zone’s DAC setup as “Decoder and Renderer” when playing an MQA track … Roon will just MQA authenticate it and then pass on the bitperfect MQA stream to DAC … letting the DAC perform all work. You can see this in the signal path…

• MQA Authentication (as before)
• Stream MQA to the DAC
• DAC performs both MQA decoding & rendering.

However, if you then enable a DSP function, Roon operates like this:

• MQA Authentication (as before)
• MQA Decode
• MQA Signaling preservation
• DSP (as selected)
• MQA Signaling restore
• Stream MQB to the DAC
• DAC identifies the stream as MQA and performs MQA rendering as directed

Hope this explanation helps.

[Tushar_das]

Thank you Carl. Decoding by DAC is better, so I guess I have to skip the Audeze LCD i4 DSP.

[Carl]

Hi again @Tushar_das,

MQA decoding is mathematical process (input A and get B out), thus the signal out of the MQA decoder is the same no matter where it is performed either by Roon or within the DAC.

Where no DSP is involved it’s down to user preference rather than if decoding in one place is better than the other … to me there is no difference so I can’t say that MQA decoding sounds better when performed within the DAC as apposed to by Roon.

However, as always with our hobby … experiment and let your own ears decided with everything else equal / constant try MQA decoding in Roon vs. in the DAC.

Personally I’d not forgo enabling the Audeze LCD i4 DSP preset just to have the decoding in the DAC.

Let us know how you get on.

[Tushar_das]

Dear Carl,

The auduze preset is really effective. So I went with it.

Regards,
Tushar.