Streaming

Get a subscription to Tidal or Spotify or Deezer (Quobuz says they will be in the US later this year).
Using the app, connect from your phone or computer to the Gungy and the Gungy goes to your preamp. 
Eeezy peezy...
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Or get a streamer from a company like Auralic or Bluesound, or various others and connect the streamer to your DAC. I use an Auralic Aries Mini in that configuration and really like it.

In the current market there is no high resolution streaming, if what you mean is live streaming from internet. The maximum quality for now is standard redbook CD, from Tidal in the US and Qobuz in Europe. The stream is compressed as a FLAC file, but this is completely transparent. So what you can get is CD quality.
To get this into your DAC you need a streamer of one kind or another. It is important that the streamer has an app(lication) for the streaming service you intend to use, like Tidal or TuneIn (for internet radio - much recommended). My preference is for widely supported streamers like Sonos, Chromecast Audio or Apple Airport Express since no service provider can afford to ignore them. These all have digital outputs, so the sound quality depends entirely on your DAC. You can use a computer for this (even a micro one like a Raspberry Pi), but I am a great fan of the Chromecast Audio. It is convenient, dirt cheap, and the digital output is bitperfect, so sonically there is nothing to worry about. Also, and unlike the Airport Express, once you have given the streaming command, the Chromecast makes a direct connection to your router, so you can turn off your tablet/smartphone. You can also use it to stream downloaded files from a NAS (even up to 24/96), but that demands a bit of computer skills (using the BubbleUPnP software). The Chromecast Audio also supports multiroom use, if that interests you. Similarly, if you have been listening in your living room and want to continue listening in the bedroom, you can simply transfer to that bedroom system. Some apps have additional functions, like a sleeptimer in the TuneIn App for internet radio (much liked by my wife).

As a preliminary step, I’ve connected with Tidal through my Oppo 105D player.
Now, how do I get programming to access extensive Classical repertoire?

Not sure I understand the question. Do you use the Oppo as a streamer? Does it have a Tidal app? In that case I assume you have to turn on the TV and use it to display the menu.
I hope others will now step in, because I don't have an Oppo nor do I use Tidal.

Tidal has one of the worst cataloging systems of all the streaming companies.
You literally have to:
1. Type the composer in the search box
2. Add the type of music (symphony/concerto/etc.) after the name.

You then get hits for albums most of the time.
Spotify has a much better organized catalog, and more complete, too.
Spotify also has a nice little 'Discover' tab that offers music related to what you have been listening to. I discovered lots of interesting new composer using that as well as 'Related Artists' when searching an artist.

FWIW, though you can get higher sampling rates on Tidal on some recordings (like MQA), most of their offerings are at the same 44Khz that Spotify outputs.
@willemj .
I believe he is using the OPPO to connect to the Tidal App. on his Ipad and then outputting to his Schiit Dac.
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Unfortunately, I have no way of connecting Spotify to my system by WiFi as I can do with Tidal.  Oppo has the Tidal app bundled with it, and I’m streaming through the Oppo. What’s worse is I can’t connect any device to my Gungnir DAC because (just a couple of months after I bought it,) the outlet for the optical cable broke. The outlet won’t hold the cable in tightly.  A washer broke off from the outlet. 
So, at this point, if I want to stream, I’m stuck with Tidal.

I haven’t wanted to send the DAC out for repair, because I’m experimenting with different tubes, and besides, I’m enjoying the system far too much.

OK. This means you are using the DAC in the Oppo, which is fine. You could even use the Oppo as a very good pre amplifier and connect it directly to your power amplifier. However, on the Oppo you only have a Tidal App and nothing for other services. Fortunately the Oppo has an optical input as well, so you could simply get yourself for example a Chromecast Audio for some $30, plus a basic $10 optical cable (with mini plug at the Chromecast end), plug it into the Oppo, and you will have access to whatever streaming service you like, and with very good audio quality. Searching for the music you want is easier if you use a tablet rather than the small screen of a smartphone.

Yes, thank you, I didn’t think of that.  The Oppo could be used as a DAC.
How do you then access the other streaming services?

If you use the Chromecast Audio, you can install apps on your phone/tablet for any service you like, be it Tidal, Spotify, TuneIn, BBC radio 3 or whatever takes your fancy. Since the Chromecast is sold in such huge numbers, there is hardly any service that does not provide an app for it. The apps are in the Google Appstore. Designing these apps is the responsibility of the service, so not all of them are equally good. TuneIn and Spotify are good, but e.g. the Qobuz app does not yet work as well as it should. There are Apps for Android devices and for Apple. The way it works is that you have the app on your phone/tablet and you use that to connect to the service you subscribe to. It will start playing music on your phone/tablet, and when you then press on the cast icon, the phone/tablet will fall silent and hand over to the Chromecast. From that moment the streaming no longer goes to your phone/tablet, but directly from the router to your Chromecast and from there to the optical input of your Oppo/Dac and the rest of your stereo system. If you then want to choose a new piece of music or whatever, you take your phone/tablet, it will reconnect to the Chromecast, and you can instruct it to stop the current music and start something else.
Since the Chromecast Audio is so cheap, you lose nothing by experimenting. Make sure you get the Audio version and not the more common video one. And don’t let anyone persuade you that it does not have a digital connection - it does, but it uses the same multifunctional mini connector for both analogue and optical digital. Just make sure you have an optical cable with the mini connector at the Chromecast end and you are fine.
I hope this clarifies it a bit.

Thank you so much for your detailed explanation.
i do appreciate it!

Gladly done. Let us know how it all ends. I think it is a great system that costs next to nothing and has no sonic drawbacks even if combined with high end components. I admit, however, that if there is a glitch I sometimes need to consult my nineteen year old son......

I use a Oppo 105 for Tidal streaming and am quite happy with it.  Access to classical can be a nuisance until you learn the system...

@jl35 .
Do you have any tricks to access Tidal classical offerings?
I, for one, would like to know.
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jl35,

I have a question too.
 I downloaded two apps: The a Tidal app and the Oppo app.
There is music offered on both apps. But I can only access the offerings on the Oppo app.  There are more and better choices on the Tidal app.
is there any way  I can utilize the music from both apps?

for classical I always look under albums, not composers. I type in the composers name and as few words as possible.  works for me

I click on Tidal on the Oppo, then use the Oppo media app

jl35,

 I retract my question. I found out how to use the “search” option on the Oppo site.
The only problem I have now is the sound quality of the Oppo DAC, which is not up to the quality of the Gungy (which I’ll now have to get fixed if I want to get better sound.)

I found if you do a detailed search (e.g. composer, work, artist) for what you want, you can get practically anything.

Unfortunately, not as complete as Spotify.

Qobuz has streaming up to 24/192, at least here in Italy (where was introduced early this year). 

I noticed the same here in Holland: hires streaming for a premium price and on all material they have in hires, and just 16/44 on the rest. I don't know the proportion they have in hires.

https://www.primephonic.com/
For classical music fans, high bit rate streaming service and much more.  I’ve not used it, just heard about it.

Which brings me to my main reason for exploring the Audiogon forums.  I want to add network streaming capability to my home stereo systems.  Which means marrying colliding systems, digital to analog.  

Which Audiogon  forum section should I go to to get help in figuring out how to get started on doing this.  I have three more than decent to mid-high quality stereo systems.  Dipping my toes into this subject makes it  look highly technical and pretty expensive.

I now have Chromecast Audio.
 I have the apps for Spotify and BBC Radio
i can access Spotify on Chromecast but not BBC.

@echolane, I suggest using the topics dropdown and selecting 'Digital'.
And, thanks for posting Primephonic. I just signed up. Unfortunately, no link with my Bluesound App.
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