Connect Macs to analog amplifier?


I have 2 systems I need to maximize the sound quality from Itunes to stereo.
My main system is a Musical Fidelity A300 that connects to a G4 laptop. (Mission 735 speakers soon to be upgraded)

My secondary system is a Nakamichi receiver with Triangle Stella ES speakers
which connects to a new MacPro Tower.

Both the MF and the Nak have only RCA jacks and I need to find an affordable way to get the most out of my digital music. I was looking in the $100-$150
range and consider Blue Circle USB Thingee, Trends Audio UD-10.2, or M-Audio Audiophile USB. Im overwhelmed as there are so many ways to do this.
Suggestions much appreciated!
xistented
I think I will get started with the Fubar 2 as that seems to be a pretty good value for the money. Did you buy the SUPPLIER Power Supply Unit or consider doing so? Not sure it's worth the extra money.........?
Hi Xistented,

To be honest I have not bought the PSU as of yet but I'm really considering making it my next purchase. The difference it makes with the headphone amplifier is just incredible. I finally got the chance to experience the headphone amp with the PSU over the weekend and I'm very impressed. Impressed enough I plan to go out and get one.

That being said, if you are just planning to get the Fubar II, IMHO the PSU is not "needed". Honestly I haven't tried it but I have no problem with the output from my DAC with the Fubar III (which has the exact same USB Dac as the Fubar II only it has the extra headphone amp build in). I would be curious if you noticed any difference with the Dac and the PSU. If you were going with the headphone amp as well I would HIGHLY recommend it, but since you chose just the Fubar II I think you would be ok with that. It does make a HUGE difference for the headphone amp though, so I guess that's something to consider in the future.

Best of luck in whatever you choose :) I hope I helped!
Cheers!
yes, you have been vey helpful in me narrowing my down my options here so i can get started on this. i think i'll get a Fubar 2 as i dont have a need for the headphone, and then maybe i will try out that PSU a little later on.

Thanks for the tips!
I had a Fubar II and the supplier power supply takes it to the next level. It's worthe the extra $110.
I have an iMac connected to an M-Audio Audiophile Firewire, Redwine Audio upgraded ClariT and some Triangle Zerius. This combination is the most enjoyable I have had regardless of price - I have a small room. I enjoy it as much as I do my vinyl - just in a different way.

I'm very happy with the sound from the M-Audio. I don't know if Firewire sounds better, but I think I will stick with that over any USB product due to the theoretical benefits.