Differences between Link 1, 2 and 3 DACs?

The AES/EBU socket connects internally to the optional 24/96 upsampling board so you will need to get a Link III to be able to use it. Some Link III chassis' have the hole precut for the AES/EBU socket, some don't. Mine does not, but when I checked with MSB they would sell the pre-wired socket for $50 and I could cut the hole with a hole-saw.

I would recommend getting the Link III just to leave you more options for future upgrades and resale consideration. The upsampling option, outboard P/S and DIP all make noticable improvements. Internal modifications from a company like ModWright can really take it to another level. The beauty of the Link DAC is that you can spend as much or as little as you want depending on what level you want to take it to.

If I had a Link III with the AES/EBU socket would it make a difference if I used it or Coax? You said it connects internally to the 24/96 upsampler, but doesn't optical and coax as well? I'm just trying to find out if there would be a significant improvement to using a certain cable type going from a Monarchy DIP to the Link.

The optical and coax inputs connect directly to the main PCB, the upsampler board plugs into a series of pins on the mainboard. I haven't used the AES/EBU input, but according to a Stereophile review it is a subtle improvement. THE best immediately audible cable improvement I have made with the Link is to use the Sound Professionals glass toslink cable,although this won't help you since I don't think the Monarch DIP has a fiber optic output. I sold mine when I installed an Audiocom Master Clock and P/S in my transport.

If you don't want to hassle with upgrades just get the Link II with the Monolithic P/S, use the coax and be done with it.If you change your mind you can always have it modified by ModWright at a later date. Good luck with your decision!

Well I plan on using the Link DAC with 2 different sources, so I will need to run optical to the DIP and coax out, then into the Link, as well as optical straight into the Link from my other source.

I hope going from optical to DIP to coax and into the Link won't hurt the signal... too much.

Yes consider the inputs/outputs of the Monarchy. I don't think it has an AES/EBU output, whereas the Audio Alchemy DTI Pro (32) has one (and I've found that the Link Dac does ALWAYS benefit from jitter reduction). But with my Link Dac II, I found that an AES from transport into the DTI Pro, and then a Canare Digiflex RCA cable from the Pro into the Link sounded good. Sometimes the digital cable into the jitter device is more important than the one OUT of the jitter device (very odd but true). In most cases optical does not sound good ever (compared to any coax) but there may be exceptions. In any case I agree with the other advice -- try to just find a Nelson Link used, since it's the easiest/cheapest way to get the whole package that does have an AES/EBU input.