How many of you believe in MQA?

Just a bit of clarification.  Larry, your Node 2i outputs Tidal/MQA by analog RCA, with the quality limitations discussed above, and by SPDIF Coaxial, but very few DACs decode MQA signals coming in that way.  The Mytek Liberty and Brooklyn DACs do, but the Pro-Ject PreBox S2 Digital does not...its MQA decoding is limited to the USB input.  With this item you do have to use a computer to stream your music...not an app on your tablet or smartphone.  But for that I'd have bought one of these myself! 
On the OP's main question, using my Tidal account and Node 2i, I find some Master files sound distictly better than regular CD quality files on Tidal...enough so to justify having the option, IMO, but some do not and in fact sound worse.  I suspect this has all to do with the integrity of the source file and less to do with the MQA process.
On balance, a desireable option, not a panacea.

I am currently looking into the Teac NT-505 as a better solution, but I am wary of the app used to control it.  I like Roon, but that's another expense.  As a Prime member I want to know if the NT-505 will be able to stream from Amazon Music.  Anyone know?

Teac nt-505 can be controlled by LUMIN app (recommended). That app is pretty good

I added a Pro-Ject S2 DAC to my Bluesound Node 2i yesterday and I am not sure I like the new sound.  I seems to sound brighter and produces more bass.  I think the bass is more punchy and the highs are brighter.  To me, it sounds harsher, unless I am hearing some of the detail I have not been hearing for the past 3 1/2 years.  I thought the Bluesound connected RCA (analogue) to my ARCAM sounded really good.  I think it might have sounded less harsh.

According to the Pro-Ject specifications, it says it can do MQA.  So, if that is the case, why did the dealer tell me when I connect the Bluesound digital coax to the Pro-Ject DAC and then RCA's to the back of my ARCAM I will not be hearing the complete unfold of MQA.  If that is the case, I will then hear one unfold and the highest resolution I will hear then will be 24 bit/88.2 kHz.  Why if the Pro-Ject is rated as MQA certified wouldn't MQA be passed through completely unfolded to my ARCAM.  This sure is confusing for someone like myself who is new to this hobby.  Maybe someone could explain this to me so I can understand.  So far, no one has been able to do so.

With Amazon Music Unlimited HD launching 2 days ago, I thought I would try adding a DAC so I could hear more songs 24/192, as it appears they offer more 24 bit albums than what TIDAL is offering.  For example, a Herbie Hancock album offered by TIDAL offers this album in CD quality (16/44.1) and the same album offered by Amazon Music is in 24/192.  If this is the case, why then be concerned with MQA?  What is the difference between listening to a FLAC recording done in 24/192 and the same recording done in MQA 24/192?  What would MQA do to that same recording to make it sound different?

My experience with MQA was through a PS Audio DirectStream Jr and was entirely positive. Some tracks I am very familiar with over decades sounded better than I had ever heard them, and I noticed the improvement without knowing they were MQA tracks and actually I didn't even know what MQA was at that point. I just noticed they sounded amazing with my (then) new Tidal subscription and started digging further to figure out why.

What I can tell you after thoroughly educating myself about MQA and digital audio in general is that nearly everything I see people write online is wrong. Most people have no concept of time resolution at all and harp on and on about frequency response, which is basically a non-issue in modern audio (modern including the last several decades) and something the human ear is far less sensitive to than time. You can take all the measurements you want but that doesn't tell you how the human ear perceives sound, just like anyone can show you a 1985 CD player measures better in every way than a record player, but lots of people think it sounds a lot worse. Alas, this MQA thing has gotten totally out of hand and people spew so much vitriol that it's become the right wing versus left wing argument of the audio world. Everyone could do well to take a deep breath and actually learn a little about what Bob Stuart has done for audio reproduction over the past 30 years before slandering everything involving the letters M, Q, and A.

That said, the simple answer to your question is you just have to listen to it. Audio is like food - there is no best and no one can tell you if what they like better is something you will like better. Try just using the BlueSound as a DAC for MQA and compare the same tracks with non-MQA versions. If you like MQA better, great, go for it. If not, don't. I'm not going to tell you vanilla ice cream is horrible and a scam because I like chocolate better. I wish people could see different file formats that way and stop telling everyone else what's good for them.

Larry5729,

“I thought the Bluesound connected RCA (analogue) to my ARCAM sounded really good. I think it might have sounded less harsh”

... this is because you prefer the dac in the bluesound over the dac in the pro-ject.

Have you even read anyones response on this thread that you started?