Is there a 'must have' 3rd party cable to improve the 846's at all?
Do you have a link at all please, just so I know I've got the correct one.
There are some new reviews out all on IEM cables. There are many top brands out there you can search for but remember the kind of metal or metals used will change the sound. Either warmer and more bass or brighter and higher treble. Some hybrids can do a little of everything.
Though I don't often listen to IEMs will sitting at my desk, when I do, it's mostly been through the Benchmark DAC2 HGC lately. That's my current favorite desktop DAC/amp for driving IEMs, as it's very resolving, very versatile, and dead quiet (in terms of background noise).
I agree with you 100%, it's a great sounding source. Probably the best I've heard. Something about desktop sources that brings out the most out of iems if the potential is there.