Carl, there are many factors that govern the *apparent* volume of your mixes, and none of them have anything to do with the Masterlink.
One of the biggest reasons is that most new music produced commercially these days is processed to death with esoteric gear to make it as LOUD as possible, under the impression that that somehow makes it "better". No dynamic range whatsoever. You cannot directly compare the *apparent* volume of your mixes against these types of recordings because you do not have access to the same types of gear that pro mastering houses have.
Also, a big factor is how you mix: for example, if you boost a guitar lead 2db at 2khz, it will sound "louder" than if you boost it 2db at 500hz - but the overall volume (what is actually read on the meters) will have increased the same amount in either case. Maybe that's not a great example, but it sort of illustrates my point: there's a lot you can do to a mix to increase it's *apparent* volume without raising it's actual volume. Everyone struggles with this issue eventually - with experience you will learn what it takes to make louder mixes.
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Audiophile: "A gate IS a compressor, A Fader is a MANUAL compressor." Pure comedy.