Do you recall "instant improvement" from your first stand-alone DAC ?

Nothing earth-shattering, IMHE. Compared to speakers, tubes, or TT, DAC differences are at best flavoring. I compared a $250 Topping D50III with a $5K Holoaudio May 2 DAC, and while there were *slightest* differences, one was not objectively better than the other. For some recordings I liked one better, for others the other. And I did a side-by-side comparison, having both plugged in, grouped in Roon, volume matched, so could switch back and forth on preamp for instant comparison.

Differences in recordings are greater than differences between delta sigma and RR DAC, so differences between DS DACs are even smaller. The is confirmed by comparing on headphones the Dragonfly series (red, black, cobalt). I had difficulties convincing myself that I heard any differences. This is at the low end of price spectrum, where one would expect the greatest improvements.

Thank you all for sharing your experiences with first DACs.  I'm trying to go into this without expectations and will be sure to take notes on familiar songs before and after.

oberoniaomnia    I compared a $250 Topping D50III with a $5K Holoaudio May 2 DAC, and while there were *slightest* differences, one was not objectively better than the other.

I agree. All DACs sounds different little. These little differences are insignificant and don't matter since veils and glare produced by separate DACs mask delicate music behind speakers. 

Also, far laid-back mid-range (human voice) in all systems (except mine) is even harder to hear. Alex/Wavetouch audio

Wavetouch audio live recording.

I'm trying to go into this without expectations and will be sure to take notes on familiar songs before and after.

The fact you started a thread here is proof that you are going into this venture with expectations. Unfortunately, expectation bias is practically impossible to circumvent. 
 

My bet is you’ll hear a notable difference, at least the first time you fire up the new DAC. Later, conduct a level-matched comparison between the WiiM and your new DAC. If you go into it with true objective intent, you will likely be surprised by the outcome. 
 

It was a bespoke design / built Standalone DAC that was the part of a Digital Source that converted me to having Analogue and Digital as a Source. 

For approx' 32 years of CD being a method to replay recorded Music, my system was not using digital. 

I know individuals who live and breathe CD as a Hard Medium Source, and apparently I fell well onto my feet with accepting this DAC that has Valves used in the circuit. 

For pure musical enjoyment and want to experience recorded music, digital in my system is parity with analogue. 

I am now looking at other forms of a digital source and will have two sources being digital at some time, in conjunction with analogue. 

Using a recorded music which is a file data that is not part of a tangible experience to manage when creating a replay, will be more like using a radio, but I do that a lot anyways.