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.
You could attach a USB DAC like a AQ Dragonfly (that only provides a 1/8 inch output and no wireless). You touched on it yourself already. The SONOS is the way to go, it can be controlled by all devices including PC. I use Spotify with my Sonos and a DAC I owned already (Sonos has digital+ analogue output). Keep in mind your getting a DAC and a wireless music streamer for $350.00! Cant beat the value. I recommend bite the bullet and get the SONOS it is amazing little device. Other external music streamers cost 700+ dollars.
Hi Matt, thank you for your suggestion. Can you comment on why you use a DAC with the SONOS? Did you just already have it or did you find the analog out quality was lacking? Which DAC to you use?
No idea of sound quality but this seems like it will do what you want and costs $130 via Amazon "Grace Digital GDI-IRDT200 Hi-Fi Internet Radio Tuner". It has wireless and ethernet jacks, digital out on toslink and coax, and analog out on RCA jacks. Or you could buy a used squeezebox. They appear here from time to time and all the time on ebay.
Look at a simple USB DAC from halide, ifi or mytech and use a laptop for streaming. I think that would be the most cost effective solution.
Spotify + Audioengine B1 Bluetooth streamer. Use phone or iPad Spotify app. Works great, sounds great, esp. with Spotify premium.
Pure I20. It is an Ipod, Iphone dock and has an internal Dac thst is better than the iphone dac. If you wanted, you could run a digital signal out of it into an external dac also.

My one and only source is a wadia 170i ipod dock with upgraded power supply. The wadia has no dac, it just bypasses the iphone dac.

Make sure you are using spotify premium though! With a good dock and dac, it is cd quality.
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.
I use a NAD wireless USB DAC1 which I bought on Ebay for $60 to stream from my apple Macbook computer. Works fine.
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
After reading the whole post, the more as I know is about Spotify music. How to convert Spotify music to common format. Since all Spotify music are DRM protected, there is no right for us to play all these download music in any format on any devices. If you really want to enjoy all these music on any devices freely, you can use a Spotify Music Converter to remove DRM protection at first. Now there are so many powerful DRM removal software on the Internet that are helpful to us. You can catch one to help you crack DRM protection and convert music to MP3, AAC, WAV, FAC, M4A, M4B, etc at faster speed with lossless quality. Wish this point is helpful to you.

Bluesound just came out with the Node 2i.  It's $499, but you may be able to pick up the previous Node 2 for quite a bit less now.  I just ordered one for $200 from my local dealer who took some in on trade.  I should have it in a few days and plan to put it in my main system.  It will stream Tidal, Spotify, Napster, Deezer, Qobuz, and a lot more.  It has an internal DAC and analog outs.  I'm planning to use my Auralic Vega for the DAC, but for what you've described the Node 2 sounds like a good option.
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