"I am presently using a squeezebox unmodded and streaming via ethernet (not wi fi) uncompressed files from a Mac. I am feeding this into my Weiss Medea DAC (tried both Toslink and coaxial). However, comparing it to using my Jason transport, the sound is significantly worse. eg in Jazz at the Pawnshop, I can hear the liveness of the recording, on the streamed music it sounds like it was recorded in an anechoic chamber. Same when i stream from my apple TV via toslink.
Has anyone found a way of streaming that actually can outdo a high end CD player?"
Technically we're not streaming when using a computer based hard-disk solution for playback, not trying to be picky, but the jargon matters. Yes, you are using an ethernet cable but streaming implies a telecommunications network, and it seems the only main distinction we can make nowadays is wired vs. wireless. A wired "ethernet" connection should offer no bandwidth concerns.
FLAC, ALAC, APE all have to be decoded upon playback, not transcoded (converted from one format to another FLAC>APE). Transcoding is a full cycle of encoded file>decoded>re-encoded.
I find it interesting that you have discovered such a marked difference with your wired connection. What is the front end software producing playback? iTunes?
Are you using the digital volume control on the squeezebox in excess?
How old is the squeezebox?
DC