Some of the discussion in this thread had me thinking, so I did a personal comp last night. I took my favorite DSD recorded song from a recent Lotus show and saved it in 24/196 and 24/48 using Audiogate to do the conversion. Then I transferred the DSD, 24/196, and 24/48 files to both my D100 and my Fiio X3 to have a listen.
After converting to 24/196, the PCM file is a larger file than the DSD file by about 50%. Even after I FLACed the file, it was still larger than the DSD file.
My listening setup was my headphone rig...the D100 or Fiio X3 headphone jack > PanAm tube-based headphone amp > Sennheiser HD700 headphones. Not the best, but certainly a higher end sound reproduction system.
I didn't spend much time comping the sound produced from the two devices. They both sound outstanding and were really close, but if I had to choose I thought the X3 sounded just slightly better than the D100.
I was a little surprised by how much better the DSD and 24/196 sound over the 24/48 files. Of course, the result is expected, but given all of the discussion over the years here on ts.com about how you don't get much from higher sample rates, I didn't expect to hear as much of a difference as I heard. Better overall clarity and depth is heard in the higher resolution files, especially in the lows.
The DSD and 24/196 files are close, but the DSD file is the fairly clear winner over the 24/196 PCM file. The DSD file has a cleaner presentation and overall more 'I'm back at the show' feel to it. The soundstage and overall air you hear is better on the DSD files.
One of these days, I'll do a similar comp, except change the sample rates at capture.