What DAC upgrade made you say “DAMN, that sounds SO MUCH better than my last DAC”?

My DAC experience thus far is always with combinations of BluRay, Pre, and streamer. DAC implementations vary quite a bit.
As many did, I started streaming with a Bluesound Node, then streamed with it to a DAC in my preamp - a noticeable improvement. I then tried a Cambridge Audio 851N and Ir was really quite good. A wow step.
I t has poor use of streaming from my NAS, so that went away. Currently using a Cocktail Audio which integrates well, and is quite decent - on a par with the DAC in my preamp. Just using the analog outs.
I tossed around the Lumin idea, but the price range is outside my priority levels.

@lalitk

I didn’t see your request for what my system is amongst all the replies. 
For digital, I’m doing a Decware Torii Mk4 amp, Schiit Saga preamp for volume control and multiple inputs, Omega 6.5 XRS floor standing speakers, a Node2i for streaming, and a Topping E30 DAC. When a recording doesn’t sound great, I use my Schiit Loki+ to EQ it. I don’t own any cables more expensive than those from Blue Jeans.

I asked my question because I’m actually quite content with how my set up sounds, yet I’ve read in some places that my DAC is “insufficient”. This got me wondering about all the claims I read about how great some DACs are vs others and whether or not there were night and day or merely incremental differences between DACs.
It seems like people have had experiences of massive changes, so I’m eagerly reading and researching!

Roon Nucleus, Farad Power supply, Bricasti M3, Pass Labs XP30, Pass Labs Aelph Zero Monoblocks. 

chorus Try an R2R DAC with a tube and no caps

Very interested to know which R2R dac has a tube output stage with no coupling cap in the signal path??
Unless it uses a transformer, then I’d op for a good quality cap, to sound better, least colored, more dynamic and more transparent.

Cheers George

Ayon audio