As long as you do not reduce the volume in the application, the result is bit perfect.
ASIO driver have direct access to the audio HW.
Also WASAPI (in exclusive mode if I remember right).
If Tital should have a possibility to play a local wav file from your computer, then you can perform the Bit test (play the WAV files that are provided by RME for this purpose). Or using an audio player.

So this is the Audirvana Studio player that routes Tidal Hi-Res music to ASIO/WASAPI/Kernel devices. Based on Audirvana tech support messages, the bit depth and sampling rate of the output stream are controlled by the device driver. So, in my case, 32-bit depth is what the RME ADI-2 ASIO driver advertised itself in Win OS. This has nothing to do with the original TIDAL stream parameters (bits/SR) or software processing (I have everything disabled, but there may be volume, upsampling/downsampling, effects, etc.).

Quote:
==============================================================================
In short:
No matter the settings in Audirvana, Audirvana always reports (in the right below corner) the maximum bitrate your DAC is capable of, this info is provided by your DAC (driver) to Audirvana.
....
Internally the 16-bit integer is passed as a 32-bit integer, because I assume your DAC is a 32-bit DAC.
16-bits passed as 32 bits is like packaging something in a slightly too large box. But what comes out is exactly the same number. So your signal is not converted or upsampled in any way. The indicator at the bottom left of Audirvana shows the original source (16-44.1 in your case) and the indicator at the bottom right shows how your DAC handles it.
==============================================================================

Is it true that the ADI-2 DAC in ASIO mode advertises itself to the OS as a 32-bit device?

P.S. Haven't done a "Bit Test" with RME files yet.

Thank you MC for confirming my guesses.

I have not used streaming platforms before, but only used local playback through Foobar2000 in ASIO mode.
It did not provide such detailed information about the process of playing files from source to destination device.
As a tech geek, I like to see and control all the details of the playback process, as implemented in Audirvana.

I finally found a software solution to route the audio of the TIDAL app for Windows to the ASIO interface of the ADI-2 DAC. Its name is VB-Audio Hi-Fi CABLE & ASIO Bridge (Donationware). Essentially, this is a Virtual Hi-Fi Cable and ASIO Bridge (XP, VISTA, WIN7, WIN8, WIN10/11 32/64 bit). https://vb-audio.com/Cable/index.htm

By setting "Hi-Fi Cable Input" as the default Windows audio playback device, selecting "ASIO MADIface USB" as the target device and turning on "ASIO Bridge", it now works fine with TIDAL application in bit-perfect mode and sample rate of ADI-2 DAC switching automatically.

In TIDAL app select 'VB-Audio Hi-Fi cable' device, turn on 'Use Exclusive Mode' and 'Force Volume'.

Notes: The buffer size in "MADIface Series Settings" needs to be set <= 2048 samples, otherwise it will cause some (unknown to me) incompatibility with ASIO Bridge.