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Igor Levin reiterates for us what distinguishes a Zodiac Gold from a Zodiac+: "As you already stated correctly there is the full-size USB port, the 384kHz future-proofing and the stepped versus continuous attenuator for added accuracy of the stereo presentation over the full range of possible attenuation. The remote is an important issue for heavy listeners with long play lists.

"The main differences in the analog output stage relate to the altered PCB architecture necessary to implement the stepped relay attenuator with its 0.1% accurate thin-film resistors. The Voltikus power supply is optional for either machine. We will have an on-demand custom bundle for a Zodiac+ with matching black power supply.

analog board

"These differences between models provide sufficient justification for the price differential. Aesthetic issues factor as well. Improved cosmetics add value. This is strongly suggested by our increased sales for the Gold. Customers seem to prefer the Gold for its price/value ratio and broader feature set. As to connecting one of our Trinity clocks, one ought to consider three different issues. From basic to top these are:

• synchronisation between components
• timing correction or jitter manipulation/reduction/elimination (Antelope AFC)
• stability achieved by a solid signal reference

"The option to connect an external clock should be considered when the target in any given system is achieving a higher representation of the digital audio data thru-put from source to destination. There are many components which transmit and receive digital audio. It's the job of the installers (professional or otherwise) to investigate the options for a given system.

Antelope Audio at High-End Munich Show with Avantgarde Acoustic integrated amplifier from Germany
and Everything But The Box monitor speakers from Bulgaria

"Regarding a Bulgarian connection, our Antelope Audio EU sales and support center is indeed located in Sofia, Bulgaria but manufacture and assembly occur in various places including China, Germany and Bulgaria. A Gold without Voltikus compares to a Plus with Voltikus with more accurate stereo imaging, higher sample rate, remote control and the bundle price for an optional Voltikus.

digital board

"About the status for the announced Windows/OSX software panel, we are working constantly on this utility to provide a very efficient user experience for controlling, updating and supporting our product from afar via the web. My assumption for the availability of the first release is April 2011. You also asked that if the Voltikus is a linear supply, how can it offer a 90-250V input acceptance. The Voltikus runs a composite architecture consisting of a linear first stage utilizing a custom toroidal transformer with an electrostatic shield between the windings followed by a switching preregulator that provides the ability to handle an extremely wide input range. The output of the preregulator goes through two linear cascaded power supplies which result in extremely low noise, the same or lower than a typical microphone phantom power supply. The linear regulators are implemented with a discrete laser-trimmed voltage reference to give much higher stability and far better noise performance that would be possible with a typical linear power supply."

Even though owners of the Zodiac+ were vocal on the forums that proper break-in meant upward of 500 hours, Antelope had again dispatched a virgin review loaner. Argh. Given the designer's explanations above, the promise of reissuing the already returned Zodiac+ loaner for a comparison seemed ill timed. Why should the Gold eclipse the Plus when the machines share the same digital and analog stages? The Gold's attenuator is the more accurate but will be irrelevant for those with preamps. Preamps also eliminate the remote as a feature. The appeal of Gold-direct drive into an amplifier had to be tested then. Beyond that it only leaves the USB cable (upscale variants with the mini connector of the Zodiac+ are still rare). Used purely as a fixed-output converter and disregarding the Voltikus which can enhance both models equally, the Gold iteration seemed to me mostly a luxo add-on of power windows and heated seats with the same engine and suspension. Why should it go any faster until 384kHz files come around? Protracted break-in initially on the bedside table with iPod, Pure's i-20 digital-direct dock, Schiit's Lyr and HifiMan's HE-6 was called for to report on properly matured results.

Voltikus power supply

On protracted break-in, reader Carsten Schmidt Christensen of Schmidt Audio introduced himself as the Danish Antelope distributor. "Having had the Gold for already 2.5 months I know both Zodiac+ and Gold very well. As you know the Plus needs a lot of burn-in to show its best. I would say more than 800 hours and yes, burn-in makes a huge difference. The Gold is a lot more extreme in every respect and therefore needs a lot more burn-in than the Plus. My unit has passed the 1.400-hour mark and still gets better every day. My guess is that 2.000 hours are needed for full burn-in. Please be aware that every input and output needs to be burned in separately. If you make the main burn-in via S/PDIF, the USB input still needs its own burn-in—I guess 300 hours will do—and again the differences are huge."

Given Igor's explanations I questioned just why Carsten believed the Zodiac Gold to be 'a lot more extreme in every respect'. The imagination is a powerful thing. Assurances of 'huge' in upscale hifi are nearly always suspect. Never mind that tracking break-in changes over 2.000 hours requires that one maintain a virgin unit and others with various degrees of time on them to conduct actual side-by-side comparisons. Anything less could be construed as a cheap trick to appease buyers who aren't completely thrilled with their purchase after the first week.

Checking with Antelope for their take on required break-in I was given 500 hours. That's 21 days non-stop. While a DAC needn't make sound to break in, it does hog a source/transport for a constant three weeks. This I confess caused me some irritation with the sender.