It's 160kbps/48kHz, which I know doesn't seem extraordinary, but it certainly improves on the FM I get. (And moreover, one doesn't have to stay up into the wee hours to hear it.)
Here's the link:
http://www.nrk.no/alltidklassiskClick on "Nettradio" on the left. A window not unlike the BBC Listen Again service will pop up. In the field marked "Søk etter program" type Notturno and click the grey box on the right of it; this will retrieve a few weeks' worth of Notturno (TTN) programmes to choose from. Once you've selected one, click "+++" where it says BANDBREDDE; this will give you the best quality audio stream.
To find what you want to hear, you will want to refer to the BBC Euroclassic Notturno schedule rather than the BBC TTN one, but it's all the same material:
http://www.bbc.co.uk/radio3/euroclassicnotturno/playlistindex.shtmlSo, for example, if you wanted to hear the concert you posted in this thread, you would use this schedule:
http://www.bbc.co.uk/radio3/euroclassicnotturno/playlist070208.shtmlOf course, the continuity is in Norwegian, but it makes little difference if you have a schedule to hand.
Addendum: Incidentally, if you want to listen to Altid Klassik live, use this:
http://media.hiof.no/streams/m3u/nrk-alltid-klassisk-172.ogg.m3u(A 172kbps OGG stream! And yet the Beeb will only give us 32kbps realaudio.

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