dumb question, streaming music to a preamp?


Hi. I am trying to put together a low cost system for my daughter, who is sharing an appartment with a few friends. We have a Luxman L-480 integrated amp and some TMM floorstanding speakers I built from a kit. She has WiFi in her appartement. She would like to use Spotify, which claims CD quality and allows you to select play lists or albums from more than 5 million albums. So how to get the music to the Luxman amp? Could buy a Sonos unit, but that is $399, which is about 1/2 the cost of everything else so far. Do not want to use a phone as have data streaming limits. Do not want to use a dedicated computer or iPad as too expensive as well. Any ideas out there. Could stream from her computer, but it just can not be tethered to the Luxman amp with a RCA cord. And if stream from her computer over WiFi, what device picks it up and converts to analog for the Luxman? Thank you for your help. This area is changing really quickly, and I have never even thought about it before.
john802
Audio Engine D2 wireless DAC works very well. One unit hooks up to usb port of computer other unit to receiver or preamp. Will play anything that is playing on computer such as spotify.
Yes my MSB Nelson DAC uses a Burr-brown chipset. Unlike the Sonos which uses a cirrus logic chipset. The MSB DAC sounds more warm and analogue, easy to listen too at higher volumes and is much more detailed. The Sonos is not bad sounding it might tend to be a little bright, that's all.
There is an NAD wireless DAC 1 on Ebay. Current bid is $20. The receiver can be set close to the integrated amp on short RCAs and the transmitter is connected to the computer via short USB cable. An inexpensive approach.
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Bluesound Node 2, self contained with integral DAC and MQA.
 Control via phone or laptop. 24 bit CD quality @$499