Ramses, wouldn't you agree that Hi-Fi, in the full "audiophile" sense, includes playback of analog sources (such as vinyl and, yes, hi-end open reel), not just digital sources? 

Accordingly, if you are that kind of audiophile, the ADI-2 Pro is a must if you want the benefits of the superb equalization features of this unit (room correction/speaker, headphone equalization) to be applied to your analog sources. I am doing it and there is no comparison between the sound quality of unequalized and equalized analog signals--particularly if you listen to properly equalized speakers in a properly corrected room when it comes to bass definition, extension, impact/slam, and overall musicality. No second thoughts about digitizing "precious" analog signal, the transparency of the ADI-2 Pro A-to-D converter circuit (being a top studio unit) is absolute by any practical standard.

dr.larkos

I understood you Ramses. My point is that, when the subject of which unit is recommended arises in this forum,  I see very often a short response like yours: "Pro FS for the Studio, DAC in front of HiFi." To me, this response implies that if you are a "Hi-Fi" user  (not a studio user) you only need the DAC.

So, I try to add my 2 cents by saying that Hi-Fi in the "audiophile" sense also includes listening to analog sources, and if that is one's case, the ADI-2 Pro, in my experience/opinion, is invaluable--actually, it is a must! Not to brag just to give proper perspective, in my a bit over $50K Hi-Fi system, Vinyl listened through the ADI-2 Pro (used in the manner and purpose I described in my previous post) sounds vastly superior than when listening without it.

Cheers...............dr.larkos

Unlike the DAC, the Pro doesn't have a true dark mode (the power button LED remains lit even when AutoDark is turned on and the other lights dim), which is the primary reason why I opted for the DAC instead. I need a way to use this device in the dark without it advertising itself by lighting the entire room. There's also the remote, which is not actually that important to me at the moment.

Other than that, the Pro is strictly better [1, 2]. Aside from the analog input, the ability to drive two independent outputs with different levels and DSP settings is pretty fantastic, and I would have been delighted to have that feature.

[1] I'm rather puzzled why the Pro FS revision, which clearly tweaked AutoDark, did not at least add a setting ("Studio Pro Mode"?) which would allow the user to choose whether the power LED would remain lit or not when AutoDark engages. I'm also puzzled at the omission of the remote control. If it is a matter of cost, then I'm sure the Pro FS could survive a small price increase relative to the original Pro, just like the retail price on the DAC has risen since its release.

[2] All right, there's also the IEM output on the DAC. Though I use IEMs with my ADI-2 device all the time, this feature is less important to me, as I'm sure the regular headphone output in low-power mode would work perfectly well.

See Handbook p49

22.2 SPDIF
Input
Two SPDIF inputs are available, optical via TOSLINK and coaxial via the included breakout cable, but only one can be used at a time.

Potential workaround: use only optical SPDIF and get an optical SPDIF switcher with remote control. Avaliable starting at about €40. Then you can select between up to 4 digital sources. Or use optical SPDIF and AES, these are separate ports.

You wrote you need both SPDIF inputs and it sounded as if you need it at the same time, so pls be more specific.
Of course you can switch between them if you would look into handbook chapter 17 "modes".

Simlpy see the blockdiagrams of each mode ... and explanations in the text if you search for "SPDIF" across the manual.

In the input section of blockdiagram you see SPDIF and a switch in the box to select between coax and optical.
"Isi pisi" .. you simply need to take a look.