You will need two things, and sometimes they come in one box. You will need a streaming device and a DAC. Simple to use streaming devices could be an Apple Airport Express, a Sonus Connect or a Google Chromecast Audio. Personally I prefer these units to dedicated audiophile streamers because these three are from brands with such a market penetration that each and every streaming service will have to provide an App - you are not locked in. These three all have an inbuilt DAC, and to be honest pretty good ones. So you could start with them and use their internal DACs first, to see if you like the system. In my own case, I use Chromecast Audio players in a number of diferent set ups, and I am rather pleased. Even in my main system with Quad 2805 electrostats the sound is very good. This of course is not surprising, given the excellent measured results with 16/44 (i.e cd quality) recordings. See here for measurements: http://archimago.blogspot.nl/2016/02/measurements-google-chromecast-audio.html
The Airport Express measures similarly well, but it is perhaps slightly less convenient because it needs continued contact with your tablet or smartphone: http://www.kenrockwell.com/apple/airport-express-audio-quality-2014.htm
If you think you can get better audio quality, you can get a DAC with optical input (all three streamers that I mentioned have optical outputs as well and produce bitperfect and hence identical digital output). Here, the sky is the limit, but the million dollar question is whether you will hear the difference, as differences will be minute at best. The Pioneer U-05 would be a very good DAC at a reasonable price, the Benchmark DAC 3 defines the high end of the market, and an Oppo UD 205 UHD Bluray player may be a very practical option, as it combines pre amplifier, UHD multi format disc player and DAC with external inputs. If you also want digital room equalization the new DSpeaker Antimode X4 will give you that, plus automatic crossover setting between main speakers and subwoofers. All four of these DACs have variable outputs (i.e. a volume control) so they can serve as pre amplifiers, but not all of them still have analogue inputs for legacy gear like turntables.
But if I compare the sound quality of even the analogue output of a Chromecast Audio with that of a good turntable like my Linn Sondek LP12, it is obvious that the 16/44 stream is far superior.
The Airport Express measures similarly well, but it is perhaps slightly less convenient because it needs continued contact with your tablet or smartphone: http://www.kenrockwell.com/apple/airport-express-audio-quality-2014.htm
If you think you can get better audio quality, you can get a DAC with optical input (all three streamers that I mentioned have optical outputs as well and produce bitperfect and hence identical digital output). Here, the sky is the limit, but the million dollar question is whether you will hear the difference, as differences will be minute at best. The Pioneer U-05 would be a very good DAC at a reasonable price, the Benchmark DAC 3 defines the high end of the market, and an Oppo UD 205 UHD Bluray player may be a very practical option, as it combines pre amplifier, UHD multi format disc player and DAC with external inputs. If you also want digital room equalization the new DSpeaker Antimode X4 will give you that, plus automatic crossover setting between main speakers and subwoofers. All four of these DACs have variable outputs (i.e. a volume control) so they can serve as pre amplifiers, but not all of them still have analogue inputs for legacy gear like turntables.
But if I compare the sound quality of even the analogue output of a Chromecast Audio with that of a good turntable like my Linn Sondek LP12, it is obvious that the 16/44 stream is far superior.
