Thanks fella's. While I've eliminated the groundloop/hum by disconnecting the laptop from the charger I'm keen on a more sustainable solution that eliminates the hum altogether. I've got a Wyred Recovery that runs off a custom made linear power supply. I'll be testing this solution sometime over the coming week. Ideally I'd like something a touch more discrete, however testing the hum with the Recovery + LPS will be a good test to see if it makes any difference at all.
The very reason I purchase the i4's over another set of full sized cans was because I wanted something portable I could use between my office and at home. We're doing a huge renovation to our place at the moment, which has meant my family and I have had to move into a (very) small apartment while the renovations are taking place. Initially I thought I'd be able to listen to the DAVE + Abyss combo, but as it's turned out due to the placement of the system I've barely touched the Abyss' because by the time I have everything setup I've either run the risk of waking one of the kids up and/or lost 15 - 20 minutes of time getting everything connected and turned on. With the i4's + Hugo2 I'm listening to music in minutes, discretely. I love that.
The i4 is without doubt the best in-ear/portable headphone I've ever owned. It's in an entirely league. I initially thought I was going to pull the trigger on the a pair of Vega's but upon listening to them I couldn't justify the price difference between the Vega's and T8Mk2's. Don't get me wrong, the Vega's are definitely a better IEM than than the T8Mk2's just not enough to justify the switch. Within 20 seconds of listening to the i4's on the first of my reference tracks I knew that I was going to buy them.
Comparing the i4's to the Abyss is a touch unfair. The Abyss is almost speaker like in it's presentation. I'm a sucker for sound-stage breath and imaging when listening to music. The Abyss lays music down across an audible plateau better than any headphone I've ever heard. The i4 comes fairly close as far soundstage and imaging is concerned. The reproduction of find details, and placement of those details is also within touching distance of the Abyss.
Then of course there's the dynamism of the Abyss', it's such an enjoyable headphone to listen to if you love scale and impact when it comes to your music. I certainly do. Some may consider the Abyss' bright, with the suggestion that the treble might be a bit peaky. I think the i4's are similar, I'm hearing a similar treble peak in there. I'm not as sensitive to treble as some so it's livable. Lastly there's the bass. The Abyss' dig deep, and have impact. While the i4's don't dig anywhere near as deep or have anywhere near the same impact there's enough resolution to create space around the bass so that there's clear delineation between the planar bass and the mid-range, ditto, mid-bass and the upper registers. All of this translates into a very visceral and organic representation of the music. The bass in particular is beautifully palpable.
This is all to say that I find the i4's stunning, and quite frankly bordering on over-whelming when I pause and start to reflect on the type of fidelity I'm able to hear in such a portable footprint. Take a bow Audeze & Chord. I'm blown away.