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.

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!