Chain of command


Greetings,
     I have an ongoing lack of understanding about what piece of equipment in the following system, actually gives the music it's final quality out to my speakers.
  
**Thumb-drive with 48000Hz, 24-bit .wav music---to Samsung Android phone---analogue out of phone's earphone jack---to input on amp---to 16 ohm speakers.**

      Will a quality amp, tube or other, influence the quality, or is it already set by the phone's DAC?
      I only want to use the phone for it's interface to select my files to play.  I have read that any DAC connected to the phone's analogue earphone jack, ...will by-pass the phone's DAC?  This comment has been both substantiated and ridiculed, so I'm at a loss here.
      Seems to me that the earliest the quality is set, that anything after will just be upsampling.  
Is my most logical route to buy a DAC with a visual screen for file selection?

Any help here....would.....ah, ....help!
Thanks.
128x128sound22card
How many thumb drives do you have?  Can you put it all on a player like an astell & kern or even a Pono?  Other choice is put it all on micro sd cards (128gb) and put them in the phone.  Use an OTG cable ($5 on Amazon) to a real DAC.  Essentially you will put a ton of music on your phone, use the usb out to a DAC and from there to an amp.
So, essentially, the headphone 'out' of the phone gives me the phone's DAC result, but using an OTG cable, out of the phone's USB will allow a connected DAC to give me it's results....but this is how I access my music (thumbdrive through an OTG into the phone's USB).  I guess what I really need is a DAC that has a USB input, and a screen to view the files on the thumbdrives.
Thanks for the clarifications, folks.
My setup at the moment:

Laptop > 3.5/RCA > Vali 2 > recvr >   /Grado/Sony HP / B&W DM600 S3.

The quality of the 3.5/RCA really does matter. Amazon Basics, once you hear the difference, just no longer cuts it.

 I am on a *very* tight budget and have found used high quality cables/interconnects here for *very* good prices, mainly because I have no problem using gear that may be a few years old.

Regardless, enjoy the journey. If you let it, it can be a blast.
I read somewhere where an Android (Samsung) phone, the Galaxy 7, puts out 16 or 24 bits, at 48 or 192kHz ...only, ...through the headphone 3.5mm jack.  If my music is 32f bits at 96000Hz on my thumbdrive then it will be demoted by the phone's DAC, correct?  Wouldn't anything after that, even a high quality DAC only be able to deliver upsampled audio?....which defeats the purpose.  (No, I probably can't hear any difference between the two. That's not the point.)  I use an OTG cable to get the audio into the phone.  Is there a way to send audio into the phone to be able to select the files, and still get it back out to a good DAC without going through the phone's DAC?
Sisyphus' punishment...WAIT...not to roll the boulder up the hill...BUT down the hill.

No, I probably can't hear any difference between the two. That's not the point