For those that have separate Streamers & DACS

Get an Aurender N20 it's the sweet spot, Aurender is a major brand with good support and resale value.

Computer based servers will have you fiddling around, forget it.

If you are positive you never want a pre-amp, I'd consider a Lumin U1.

People will try to confuse you with esoteric and exotic brands but where will they be in a few years?

An N20 is the best bang you'll get this side of 20 grand.

I started with a Raspberry Pi, which worked quite well, then "traded up" to an Aurender, which didn't. I dumped that in favor of a Bryston BDP-3 and have been happy ever since.

Visit resellers, audition what your research tells you could be options.

Make a shortlist, then...

You have to audition in your own system / environment. If you can't get a home audition, then cross that dealer / brand off your list.

Try with internal and external DAC's.

Try direct into pre-amp.

Take your time, your choice is important to YOU. 

I'm using iFi Zen Streamer USB to Wyred4Sound DAC2v2SE. The iFi Zen was a little kludgey for initial setup but it sounds far better than I expected. At a $399 price point I wasn't expecting much and I'm still pleasantly surprised.

The Zen stream was an interim purchase for me as my previous streamer had died and I needed something quick. I assumed I'd be trading up within a few months of finding my next streamer.

Maybe not though. I'm still really enjoying the heck out of the iFi zen. And I've got a Matrix Audio X-SPDIF 2 on the way to serve as an I2S converter between the USB iFi Zen and the I2S interface on the DAC.