What exactly is Roon doing on when it “decodes” native 44.1 kHz to 88.2?

That is when the version is 24\44.1 what is a Roon doing when it decodes it to 88.2, when the original high res file the MQA is based on is 24/44.1?


That’s a question for MQA Ltd… All MQA is encapsulated as 2x sample rate “MQA Core”, even if the original sample rate is 44.1kHz or 48kHz.

“All” that Roon is doing is using the MQA decoder to extract the 2x rate MQA Core audio from the 1x rate folded MQA file.

I imagine that the master used to create the MQA encode was actually 16-bit. The extra 8 bits in the MQA container are used for the encapsulation/folding process.

MQA filter also play a part here. MQA filter typically has a roll-off above 44.1/48kHz frequency response, not 22.05/24KHz as most standard filters are used. Therefore the MQA core needs to always output 88.2/96kHz regardless whether it is mastered originally in 44.1/48kHz or higher. The authentication is the only information that shows the actual mastered sample.