Pros: No compromise sound quality. Beautiful. Exceptional build quality. Forward-thinking design.
Cons: I wish it had a couple more S/PDIF inputs.
The Zodiac Gold with Voltikus is gorgeous, there's no denying it, and its flawless satin finish is just the start. Even the small remote murmurs "High Quality", because it feels like solid aluminum. You could knock someone out if you threw it at them. The ZG isn't just a pretty face either, the knobs and buttons all have a wonderfully smooth feel. The whole time you use it you're thinking, "this is an impressive chunk of gear". For me the icing on the cake is the .05dB stepped attenuator, the fine control is amazingly accurate.
Quite frankly, I've not found a fault in its performance yet; it's perfectly transparent and stunningly detailed. It has no coloration at all, it's dead neutral, and all the headphones I've tried with it have benefited from this. It completely steps out of the way and, for good or ill, lets the material and transducers perform the way they're intended. Oh, and the Ultra-Linear, dual stage headphone amp is the real deal, and it's all about damping factor. My Fostex TH900s are fussy about this, and with the wrong amp the bass bloat can be unsightly. No worries about that with the Gold. Select 0Ω output mode, and like Ms. Jackson, the key word is Control. It has lots of it. Imaging? Like no other amp I've tested. It's so remarkably vivid that I actually fiddled around to see if any 3D effects were somehow enabled. No joke.
As you'd expect, then, the dynamics are out of this world, I've not heard the ZG place a hoof out of line... That is, except when driving my HE-6s, the fact is, it doesn't have enough juice for them. The mids and highs are amazing but bass performance just isn't... quite... there... I expected this. In fact, I would have been stunned senseless if it had pulled it off, so I'm not disappointed in the least. Otherwise, everything I tossed its way it caught with ease and elegance. Given the designer's roots in high-end production and mastering hardware, it's not hard to suss out why.
Now it's time for numbers and maths, courtesy of the Antelope site:
Dynamic Range: 129 dB
THD + N: 0.0004 %
USB: 2.0 Hi-Speed. Data stream up to 480Mbits/384kHz, Type B
Clocking System: 4th Generation Acoustically Focused Clocking 64 bit DDS Oven Controlled Crystal Oscillator
Clock Stability: < +/- 0.02 PPM, oven controlled at 64.5 C
Clock Aging: < 1 ppm per year
Sample Rates: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz, (352.8kHz, 384kHz through USB only)
To completely take advantage of its features, I now have all my head-fi gear attached to the Zodiac, and it pulls duty as a DAC, amp, or DAC filter. Yeah, it actually re-clocks and de-jitters all digital signals coming in (they call it Acoustically Focused Clocking) and outputs the "cleaned up" product via AES or a pair of S/PDIF connections. I'm not really sure if it makes that much of a difference, but it seems cool none-the-less. So far my only gripe is with the USB, twice when I've switched from a different source I had to disconnect and reconnect the USB before it worked properly. It doesn't drive me nuts, but if it becomes a habit it could get annoying. I hear Antelope's working on a firmware patch to fix this, so that may be a non-issue soon.
The short and sweet. Am I keeping it? There's no need to even ask. Benchmark is no longer the true benchmark around here, that honor belongs to the Zodiac. This Antelope really whips the llama's ass.
PS. Oh, and when they fix the USB issue I'll give them their fifth point in design, not a second before.
Update 11/17/13: Ever since updating my USB drivers to the newest version, the problem with losing connection has gone away. All's well, but Antelope wasn't the one who fixed the problem, so other people could potentially have this issue in the future if they're using an older driver. Of course, the probable fix is to update to the newest ones, likely you'll find them at your PC or motherboard manufacturer's website.