Amarra for iTunes at RMAF...

Mrjstark, see the review in 6moons on the Minerva http://www.6moons.com/audioreviews/weiss2/minerva.html
from all that I have learned, you want to avoid USB2. I am getting a Mac Mini for what the Sonic Studios setup says.
http://www.sonicstudio.com/amarra/support/howtobuildaserver.html
I am getting the big one, but you will have to get an external raid hard drive with firewire connections.

I have experimented extensively with Amarra, and wouldn't be without it.

The best solution I found was to use a powerful Mac (more power is a good thing) with 8GB of RAM (more RAM is a good thing), Amarra/iTunes, and outputting through an Empirical Offramp 3 and an excellent USB cable (I like the Offramp as it allows me a world of DAC choices).

I also found that with my 24/96 DAC, I was best to convert all my files to 24/96 and store them at that resolution, uncompressed. Its a bit like the idea of feeding your LCD with a file that matches its natural resolution. This takes load off both the Mac (no unpacking of ALAC files on the fly), and off the DAC (no real-time upsampling to do). Both can then work more accurately. And you really should dedicate a Mac to the task, not use it for anything else.

Peoples' preferences about upsampling versus 'native' blends/confuses two different issues. Upsampling, if done well can be very beneficial, up to a point (which depends on your DAC chip), but doing it in real time taxes your DAC's performance. I use AIFF as it can handle tags etc, unlike WAV, and use SampleManager software for the conversion to 24/96.

Remember that the digital to analog conversion essentially upsamples in the way that it joins the dots in the analog domain between the discrete samples. Different algorithms for joining the dots sound different, even though the imaginary data is supposedly beyond our hearing range. There is a trade-off between how much of the imaginary data is done in the digital domain (upsampling) and how much is done by the DAC process. Doing it offline is a good thing as I have said before, but there is a limit to how high you should upsample - mainly based on whether your DAC works well (or at all) at the higher bit rate.

Antipodes_Audio, thanks for your thoughts regarding mac/Amarra implementation. I am also using an Empirical Audio Offramp 3, with a Locus Design Axis usb cable from my mac mini. The mac mini is upgradeable to 4gb of RAM (it will only utilize 3.5gb of that), and I have done that with mine, which I use as a music server only. I would guess there are a lot of people using the mini as a music server, due to it's unobtrusiveness. I keep my mini on the stereo rack and run a cable from it to the tv on the other side of the room, and use the tv as monitor when needed. So, no monitor on the stereo rack.
Regarding converting your files to 24 bit and storing them at that rate, what program do you use for this? I'm getting ready to rip some standard 16 bit cd's and may try what you're doing. It sounds logical, although I'm not fully convinced it would be beneficial.
BTW, do you use the Amarra mini of full version?

HeyMikey, I am using Amarra mini at this stage but also ran the full version for a month's trial before deciding. I may upgrade to the full version later, but its only advantages for me would be the higher sampling than 96kHz and I am currently limited to 96kHz by both my DAC and the Offramp. I note that Dan Lavry holds strongly to the view that upsampling to 96kHz is still better than upsampling to 192kHz, so I am not fretting about that one.

I converted my files using Sample Manager, which you can find at http://www.audiofile-engineering.com/samplemanager/. Use the iZotope options for resampling and redithering. iZotope is the best sounding set of algorithms that I have tried, and it seems that many in the industry use it.

The redithering to 24 bit provided the most significant improvement, more so than the upsampling.

The hassle with Sample Manager is that you can only batch convert around 100 files at a time or some cache fills up and the program has to be restarted.

It was recommended to me that the best process is to redither to 24 bits first, and resample second - which I just accepted and didn't test myself.

I recommend you make yourself a 24 bit version of a few songs, a 96 kHz version and a 24/96 version and then compare them with a 16/44.1 version of the file. Trying this out for myself with a DAC that upconverts to 96kHz, I preferred the 24/96 file. Trying this with a NOS DAC where the sampling rate is switchable between 44.1, 48, 88, and 96, I also preferred the 24/96 file.

For those that are interested in such things, I do employ double blind tests routinely, but in a way that is helpful as opposed to confusing - but to describe it here would be a long post.

I experimented with Amarra.

Macbook with 4gb Ram and SSD HD.

I returned the ilok for a refund.

I'll live with iTunes and a PWT until Audiofile-Engineering comes out with their playback software.