Hi
Need a way to listen to my files currently on a hard drive. I have organized these by Folders. I listen mostly to Spotify , followed by Apple Music Classical and regular. I need a way to listen to my files, and to train the AI/Algorithm of my favorites streaming services, especially Apple Classical.
A decent device with a good interface. I believe Human Interface is a neglected area. So far the easiest to use to Stream to my audio system is Spotify Connect and by far, Apple, usually very good in Human Interfaces miffed this one: , it is downright counterintuitive. People find their ways through it, but we would find our ways though anything so .. not a good score for Apple on that one.
Budget is very ASR-ish

(aka low, dirt level) .. I need it to work, while spending as little amoutn as necesary and hopefuly Amazon-next day ...
What do you suggest . People?
You raise a very good question - many of us are dealing with similar situations.
Lots of good advice from others so far, but
@chelgrian gets to the core issue: if you want a combination of
Apple Music streaming and
local hard drive-based playback, that limits your choices and makes any solution more complicated. This is NOT because what you want is unreasonable - not at all. It's just the result of the limited or nonexistent support for Apple services and protocols by some third-party vendors.
Ideally the best all-around device is probably something from Wiim - among the best user interfaces, very good product support, good control over maintaining lossless (and depending on how you use it, bit-perfect) quality, good product design, and affordable hardware. The problem is that the newest Wiim devices have USB ports that allow you to connect your HDD to them, BUT they don't support Airplay2, and no Wiim devices have built-in apps/support for Apple Music. And conversely, older but still current-production Wiim devices DO support Airplay2, but those particular Wiim devices do NOT have the USB ports that allow you to connect your HDD to them. You can't get both Airplay AND local USB connection in any Wiim device,
Here, in no particular order, are a few possible setups that could work for you, but they all have at least one "wrinkle" or drawback that you would have to deal with.
1. Get a Wiim Mini, Pro or Pro Plus. Like all the options here, this will connect to your audio system (though some of these options may require your audio system to have a digital input, while other of these options can be used with a digital or analogue input). You cannot connect your HDD to these Wiim devices, however.
So you'd have to have a computer on your local network running a DLNA server like Plex. Plex is 100% free to use this way (it has some paid features but you don't need to worry about that). It's really easy to set up too, and the Wiim devices natively support Plex. The downside is that you have to have a computer running 24/7 on your home network and it can't go to sleep (although if it has a screen it's of course fine if the screen goes dark, which will save a good deal of power).
To stream Apple Music you would simply open the app on your iPhone, select the Wiim as your Airplay destination for the sound, and tap Play. To stream your HDD files you would open the free (and excellent IMHO) Wiim Home app on your iPhone, tap Browse, tap Plex, then select whatever album or track you want and tap Play. To play Spotify, I believe you could either use the Spotify Connect app on your phone, or use the Wiim Home app and select Spotify within that - I'm not a Spotify expert but I think either method would work. Even if I'm wrong in the details, the point is that Spotify streaming with a Wiim device is super easy.
The one sonic downside of this setup is that while the HDD and Spotify sources would play at whatever their native/maximum quality is, the Apple Music stream from your phone to the Wiim device would be limited to lossy 256k AAC. Personally I prefer lossless - but on the other hand I very much doubt I could tell the difference between most 256k AAC content and lossless content if I had to take a blind test. So whether that matters is up to you.
And of course the real downside is that you'd have to have a computer involved, and you'd have to learn at least a little bit about setting up a network DLNA server if you don't already know how to do that. It's easy, but I of course respect that you might not want to deal with it.
2. Get a Wiim Ultra and a FiiO SR11. The Wiim Ultra has more features than the Mini, Pro, and Pro Plus, and the built-in DAC and associated circuitry is technically superior, though whether it makes any audible difference is doubtful. (The Ultra also has a really nice small built-in status/control display if that matters to you). You could connect your HDD directly to the Ultra, so you wouldn't need to have a computer involved in any way. The first time you connect the HDD to the USB port of the Ultra, it has to scan and index all the music files, but that's a one-time thing. Once that's done, to play music from your HDD you just go into the Wiim Home app, tap Browse, then tap USB, and your entire HDD library is right there for you to select music and tap Play.
For Spotify, it's the identical setup and experience to option 1 above.
For Apple Music, the Ultra won't work (except via Bluetooth, but yuk!). That's where the FiiO SR11 comes in. The SR11 supports Airplay1. Airplay1 has fewer features than Airplay2 - but the big advantage of Airplay1 is that it always streams in lossless 16/44.1 CD quality - no lossy AAC (as long as the original music source is lossless of course). The SR11 has an optical digital output. You would use an inexpensive optical digital cable to connect the SR11 to the optical digital input on your Ultra.
In this setup, to stream Apple Music you would open the Wiim Home app on your iPhone, tap Browse, and then tap Optical. (Or you could just use the physical remote control included with the Ultra to switch to the optical input.) That would set the Ultra to receive input from the SR11. Then you'd open Apple Music on your iPhone, select the SR11 as your Airplay destination for the audio, and then just select some music and tap Play.
In this scenario there are two downsides. One is that it's the most expensive of the options. The Wiim Ultra is their most expensive streamer at $349, and you have to pay an extra $100 or so for the SR11 and have that extra device connected to your main streamer, the Ultra. The other is that to stream music from Apple Music to your audio system, you'd have to do that small extra step of switching the Wiim to its optical input before using the Apple Music app on your iPhone to start playing the music. If you don't mind spending the money, though, this might be the ideal solution. And as a new and happy Ultra owner myself, I can say that if I needed Airplay capability, this is the route I would go.
3. Get an AppleTV. This is essentially an all-Apple version of option #1 above, except the AppleTV lacks a built-in DAC and so it only has a digital output. You can stream Apple Music directly to the AppleTV device, and the AppleTV app store has free native apps for Spotify and other streaming services so you can easily use Spotify Connect on your phone to stream to the AppleTV. The AppleTV's Apple Music streaming can also be controlled from your iPhone with Apple's own Remote app or the Apple Music app.
But the AppleTV outputs everything in 48kHz sample-rate format (it might also limit everything to 16-bit, but I seem to recall reading something recently that said that wasn't necessarily the case). So most of your musical sources will be resampled (and possibly reduced in bit-depth). Now again, whether that's audible is questionable, and I would say unlikely, as 16/48k lossless is perfectly adequate for hi-fi and proper sample-rate conversion is trivially easy for modern gear. But if it's important to you, it's something to be aware of.
And while the AppleTV's own interface is excellent, I find that the Apple iPhone apps like the Music app and especially the Remote app are more limited and not as easy or pleasant to use as the Wiim Home app is.
Finally, the biggest downside of the AppleTV option is the same issue as option 1 above: the AppleTV does not allow you to directly connect a drive via USB. So you have to stream from your HDD to the AppleTV over your network, which in most cases means having a computer running 24/7 to serve your HDD's files to the AppleTV over a network connection. So unless having an Apple-made streamer really appeals to you, this option has all the downsides of option 1, plus less bit-perfect playback and no built-in DAC.
4. Get a FiiO SR11 and use it by itself with no Wiim device at all. I can't tell from your post if you actively use Spotify, or if you were just using Spotify as an example of a better user interface than Apple Music. If you would be okay just using your HDD and Apple Music, then you could potentially just get the FiiO SR11. It supports Apple Music streaming via Airplay1 as I've noted above, and it allows for direct connection of a USB device like your HDD. As far as I know, however, it does not support Spotify Connect.
With this option, you'd stream Apple Music just like the first part of the process in option 2 above: You'd just fire up Apple Music on your phone, select the SR11 as your Airplay destination, and start playing music. Super easy. To play from your HDD connected to the SR11, you'd use the free FiiO Control iPhone app to switch the SR11 to its "Local" input, and then use the FiiO Control app to play the music.
Aside from the obvious downside of no native Spotify integration, the one other downside is that I don't know how the FiiO Control app user experience compares to the others in the previous options. Based on the few screenshots of the phone app on FiiO's webpage for the SR11, I'd guess the FiiO Control app is probably in between the Apple Remote app and the Wiim Home app in terms of user experience, features, display options, and so on.
But on the upside, if you don't need Spotify, the FiiO SR11 is the only one of these options that only requires a single device - and it's also the cheapest overall option at just over $100 with no additional equipment needed.
Just be aware that the SR11 is a digital streamer only - your audio system needs a digital input, or else you have to get a separate DAC.
4a. Get a FiiO SR11 and a Wiim Pro. Think of this as the budget version of Option 2, or as a version of Option 4 that will inexpensively add both a DAC and Spotify capability. This option is very similar to option 2 (Wiim Ultra plus FiiO SR11). But in this case while you would still connect the SR11 to the Wiim's optical digital input, your HDD would be connected to the SR11 (since unlike the Wiim Ultra, the Wiim Pro does not have a USB port for that).
In this scenario Spotify streaming would be simple, same as in options 1 and 2. And Apple Music streaming would be the same as in option 2 (set the Wiim Pro's input to optical and then use your Apple Music phone app to stream to the SR11, which in turn will feed the Wiim). The one difference here is that to play music from your HDD you'd have to set the Wiim Pro to its optical input so it could receive music from the SR11, and THEN you'd have to use the FiiO Control app to set the SR11's own input to "Local" to access your HDD. Then you'd also use the FiiO Control app to select and play music from your HDD.
This option is exactly like option 2 - Spotify, Apple Music, and local HDD with no computer - except it adds an extra input-selection step for your HDD music, and in exchange for that it costs a bit less money (becuase the Wiim Pro is cheaper than the Wiim Ultra).
I hope this helps!