I know Roon does the 1st unfold, but is it good enough?

As well you should. The truth is that there is nothing to the MQA marketing speak called “2nd fold” other than upsampling at the DAC with slow rolloff, high IMD “min phase” filters. Even MQA supporters such as John Atkinson (technical editor for Stereophile) and Jim Austin (Editor of Stereophile) admit this is the case. Bob Stuart himself does as well, in a round about way, but you have to read between the lines of his/MQA non-standard use of signal processing terms (e.g., “resolution”, etc.).

see: Lies, damned lies, and ~~statistics~~ MQA

2 Likes