asinghji,
As to DAC match with the Torii, I can't imagine that any really good DAC with the Torii could be a bad match.
I think the main thing is that the Torii is very revealing, and the better the amp, and all that is downstream, the more important the front end is. It is after all the beginning of the music. So if your computer, cable or DAC truncates the data, or negatively effects the analog in any way, it is just damaged.
This points to starting with a computer that is well suited to the music serving (powerful enough, quiet, well isolated from vibration), a well optimized computer (most processing other than music serving cut off, adequate memory, and good player software), a good cable to DAC, a good DAC that effectively isolates noise and jitter, and good IC's to the Torii.
I use a 2010 Mac Mini, which is known to be very quiet, powerful enough, very easy to use, and easily adaptable to cut out extraneous processing that can effect the audio out. There is more to look at on the USB cable than just 1's and 0's. The computer itself can truncate data and make noise before the cable. And once on the cable there is potential for analog noise as well as micro timing issues (jitter) and data truncation between the DAC and computer.
I use all files without any compression since the decompression from ALAC or FLAC to the original WAV or AIFF format can cost computer power and potentially increase noise and timing issues. Subtle to reportedly indiscernible with a good computer, but real. I heard it with my battery operated Macbook Pro when I first explored Lossless or not.
The bottom line for fidelity with your Torii? If your room, speakers, cables and AC power are all up to the Torii, you will potentially hear everything including differences in power cable sound, ICs, which feet you use under you gear....seriously...everything. So starting off with better stuff as you are asking about is a very good idea to get the most cohesive possibilities from your new amp. Also: the computer you use matters, how it is set up matters, the file types you use, even lossless can matter, the cables you use matter, the DAC matters and the ICs matter.
If you are not familiar with the following links, they might be useful.
http://www.computeraudiophile.com/ check the FAQs first
http://www.audiocircle.com/index.php?topic=74816.0 This is about the Tranquility DAC which I use. I got a pristine open box for 1000, but then there are power, IC, and USB cables. It is a great DAC, but if you skim this thread you will find some good info on computer serving, whether you are interested in the Tranquility or not.
http://www.digitalaudioreview.net.au/ If you have not been here before, his opinion of course, but this guy has some interesting reviews on DACs.
Also there are a few threads on these Decware forums about computer stuff....maybe in the ZDAC area??? and scattered around in areas where the threads wondered.
As with the Torii, Decware stuff is reasonable for the value. There are a few ICs for sale now in the classified section of this forum. The Zen Styx are also really good speaker cables and reportedly, the Power cable is very good, though I have not tried it. All are reasonably priced for the quality. Also, I use some MAC power and IC cables that can be very nice and bought inexpensively on audiogon auctions, and one other site. If you look at myaudiocable.com (MAC) you can see something about the other auction site. I particularly like their UltraSilver IC, though retail to retail, it is not twice as good as the decware IC, I like it a bit better, and if you can get one for 50-60 like I did, it is a major bargain.