Using Apple Remote to stream music through Apple TV 2

Hi all

I have what may amount to a really silly question, but your help in answering it would be much appreciated nonetheless.

I have a Macbook Pro, an Apple TV 2, and an iPad 2 with the Apple Remote app. Having converted all my ripped music to lossless files, I am thinking of buying a new hifi. The one I have in mind (given budget restrictions) does not have Airplay. To stream my lossless tracks from my iTunes library I am thinking of either using the Apple TV 2 connected to the optical input at the back of the hifi, or buying an Airport Express (as I understand the Apple TV makes some adjustment when playing sound files where Airport Express just plays them without any conversion).

My plan is to use the Apple Remote app to control playback. The app has two options - one to control the Apple TV like a remote control, the other seems to take control of my iTunes library. I plan to use this library screen to instruct the Apple TV/Airport Express to stream the music and play it through the hifi. My question is this. If I open the Remote App and select the streaming device and play the tracks from the library screen in the app, are the files streaming direct from my laptop to the streaming device, or are they first streaming to the iPad then to the streaming device? Are they streaming using Airplay or something else? Either way, am I still guaranteed accurate lossless playback through the streaming device, or do I have to go and control Airplay from my laptop?

Hope the question is clear enough, and any help appreciated.