Hi there folks!
I mostly use Roon so not very familiar with Audirvana, but trying to play hi resolution material on my Devialet Phantoms has had me rediscovering Audirvana since Roon doesn’t support UPnP.
I have Audirvana connected to both Qobuz and Tidal and playing various hi res albums on Tidal got me curious about MQA, so I started fiddling about and trying to understand exactly what the setting do. There are two relevant settings in Audirvana as far as I can see:
- “Auto-detect MQA devices” (toggle on/off). While the intention here might be clear, the actual effect is not, and I can’t find any documentation. Could it be that if set to “off” the actual behaviour of Audirvana is determined by setting 2. and if set to “on” Audirvana selects the optimum behaviour based on whatever capabilities the DAC presents?
- “DAC not detected as MQA, use as” (not MQA/MQA renderer, MQA decoder). According to my understanding there are only two alternatives here, either Audirvana performs software decoding or it doesn’t (correct?). So why three options? Using the DAC as a decoder means that Audirvana should not perform software decoding, and using it as a renderer means it should, but what about “not MQA”? In this case does Audirvana perform software decoding and send 24/88.2 or 24/96 or not and send the 24/44.1 or 24/48 original file?
To try to answer the above I tested playing the MQA (24/192) version of Norah Jones Come Away with Me from Tidal on both a Dragonfly Red (MQA-capable) and a Meridian Explorer (not MQA-capable). I tried all three settings for “DAC not detected as MQA, use as” with the “Auto-detect MQA devices” switch both on and off (the results in both cases were the same for both DACs so what this switch does is a bit of a mystery. Whatever it does it does not seem to influence whether the decoder in Audirvana is engaged or not).
The results for the Explorer were:
not MQA: Audirvana reports sending 24/96, confirmed by Explorer
MQA renderer: Audirvana sends 24/96, confirmed by Explorer
MQA decoder: Audirvana sends 24/48, confirmed by Explorer
The results with the Dragonfly were:
not MQA: Audirvana reports sending 24/96, Dragonfly lights Magenta indicating 96KHz
MQA renderer: Audirvana sends 24/96, Dragonfly lights purple indicating “MQA”
MQA decoder: Audirvana sends 24/48, Dragonfly lights blue indicating 48KHz
So, it seems that my suspicions were correct inasmuch as Audirvana performs core decoding (first unfold) regardless of whether the “use as” switch is set to “no MQA” or “MQA renderer” (but not if it is set to “MQA decoder”). Presumably then “MQA renderer” signals to an MQA renderer to perform the second unfold, whereas “not MQA” doesn’t (and this presumably only in manual mode whereas the decision is taken automatically in “Auto-detect” mode?). Unfortunately since the Dragonfly is limited to 24/96 and the result is the same regardless this is impossible for me to prove.
What I can conclude however is that Audirvana performs the first unfold if the receiving DAC is capable of processing the higher bitrate, regardless of whether it is MQA-capable or not, and that the only way of stopping it is to set “use as” to “MQA decoder”. So the purpose of two switches and three settings is still a bit of a mystery to me.
Grateful for any clues for the clueless!