After owning the Zodiac plus for over a year with 1000+ hours on it, I would like to share my impressions of the Zodiac plus. To start off, I don't think there can be a fair evaluation of the Zodiac until it is fully broken in. As many have already stated, the DAC takes a long time to break-in to reach its potential.
During the break-in period, I had a love-hate relationship with the DAC and contemplated selling it on numerous occasions. At times, the Zodiac would sound harsh, sibilant and fatiguing, weaknesses that were hard to swallow given the price, and I much preferred the sound of my other DAC, an audio-gd reference 7.0 that is almost like the Zodiac's antithesis in terms of being on the warmer and darker side.
However, I am glad that I stuck it out, because the Zodiac has reached a level that now surpasses the reference 7.0 in my system. Now that the sound has settled (i.e., sound quality is pretty consistent), the best word to describe the tonal balance of this DAC is "beautiful." There is hardly any residue of the harshness, sibilance, and fatigue from early on. The sound has become very smooth, musical, and sweet. It is also neutral without sounding clinical, and I would say one of its strengths is the layering of sounds I recall another review on this site that described the sound signature as "wet" - I am not sure what connotation this description has, but I'm guessing the reviewer was referring to its lushness.
Compared to the reference 7.0, the treble extends higher but there is no longer any harshness, and there is better layering of sounds that adds to depth of soundstage. The reference 7.0 still has advantage in wider and taller soundstage. The lower region took the longest to fully form with break-in, and now there is a solidity and weight to the imaging that gives the impression that vocals and instruments are on leveled on the same sound stage, and gives a presence of the musicians as opposed to sounds that are just floating in air.
To give some context to my impressions, my system entails the following: FLAC --> Transporter --> AES ---> Zodiac Plus --> XLR --> Audio-gd Master 8 --> HE-6, LCD-2, HD-650 /// --> Audio-gd Master 3 --> Magnepan 3.6. Power conditioner is Equitech Son of Q.
I have found the Zodiac Plus to have decent synergy with all components I have paired it with. Its interesting that even using the de-jittered digital out to another DAC imparts the Zodiac sound signature, which gives me impression that digital section of Zodiac is quite robust.
I would like to add that it took some tweaking to get best sound of the DAC. Here are tweaks based on order of improvement:
1. After-market power supply: I think this is a must. The sound is a bit thin without the after-market PSU. I use a reasonably priced one from Wellborne. It seems like the Volitikus is the gold standard though.
2. Power cable: The Zodiac seems sensitive to power cables, and I've had best luck with PCs that known to be musical. I experimented with quite a few and settled on a custom one that a friend made and sold me for $100. I also used a entry level Synergistic Research PC (paid $50 used) that worked well. I don't think you have a break the bank to get a PC with good synergy, but I think experimentation is important.
3. Vibration footer: The footer made a minimal improvement, but I noticed right away that the bass went deeper with the footers. I was able to replicate this subtle change by A-B with and without footer. I used some cheap sorthobane ones that I got for $30 or so. I put them directly under the current footers.
4. Interconnects: The different digital cables and XLR cables I tried didn't seem to change sound much. I settled on DH Labs Silversonic AES cable, and Norse Audio XLR cable.
Regarding my impressions, I go back and forth between my DACs so I don't think my impressions are merely based on my ears adjusting to the sound of Zodiac. I believe the break-in time for Zodiac is very real and it requires some tweaking to reach its full potential.
Thanks for reading!
Edited by BoyNamedSue - 3/16/13 at 8:57pm