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Reviewers: Frederic Beudot, Srajan  Ebaen
Digital Source: Esoteric X-03SE
Preamplifier: NAT Symmetrical [in for review], Accustic Arts Preamp I mk3 [on loan]
Amplifier: Genesis Reference 360, McIntosh MA2275
Speakers: FJ OMs, Rogers LS 3/5a, Genesis G7.1f [in for review]
Cables: Zu Varial, Zu Libtec, Esoteric Mexcel 7N-DA2100 Balanced interconnects [on loan], Accustic Arts Silverline Balanced [on loan]

Power Cords: Zu Mother, Isotek Power, NAT Black [on loan], Accustic Arts Ferrite II [on loan]
Powerline conditioning: Monster Power HTS5100mkII
Sundry accessories: Isolpads under electronics
Room size: 12' x 13.5' x 8'.
Review component retail:

Our Editor's previous review of the Esoteric A-100 tube amplifier included detailed technical descriptions of Esoteric's first standalone preamplifier but its sound commentary was cut short by his move from Cyprus to Switzerland. We thus felt that more remained to be said and our combined follow-up today takes care of that, with me in the main role and our Editor in a sidebar at review's end.

I won't repeat the C03's features and construction; this was already covered in exceptional detail here. I'll just make two additional comments. To my extreme surprise, the C03 is fully un-balanced. Unlike its vanishing noise and distortion specs would seem to indicate, the C03 is a single-ended design. According to Esoteric, they had reached such low measurements that adding balanced complexity actually increased noise to mandate going with a single-ended circuit instead. This quite turns upside-down general wisdom or even other Esoteric designs which always have been praised for the excellence and superiority of their balanced connections. It's also testimony to the intellectual honesty of Esoteric's engineers who transcended preconceived ideas to deliver the best component they could conceive of.

The purest signal path through this preamplifier is actually with the RCA connections but I could not spot any loss of detail or tonal elegance going in and out of the pseudo-balanced sockets. That's quite an achievement and similar to the completely versatile SMc Audio VRE-1, my reference thus far for insensitivity to the type of connection used.

My second comment regards the lack of fixed outputs allegedly to preserve sonic purity. In my book Steve McCormack's VRE-1 has yet to be dethroned when it comes to absolute transparency and respect for instrumental micro textures. Yet it offers a fixed output that can be switched off for those without use for it who want to remove this possible source of signal degradation from the circuit. Esoteric's C03 offers relay-activated inputs and outputs which allow switching out any unwanted connection from the circuit including its ground. I thus have a hard time accepting that the same functionality could not be extended to a fixed output without impacting sonics. And that's the extent of my complaints since this is really the only negative I have to offer on the C03. From here on out it's all smiles 'n' roses even though roses do show thorns on occasion.

I am not sure it is really feasible to convey just how well thought-through and executed the C03 truly is. Just to list a few of its almost endless features, each input can be individually named (freely or from a pre-populated list) and gain-trimmed over a +/- 18dB range for level matching and the inputs not used can be skipped to not appear when toggling through sources. The C03 can easily be a single source preamplifier.
In Srajan's system, the second RCA input is for the Yamamoto YDA-01 DAC and accordingly named YDA01 which is easily accomplished with the alphanumerical input naming feature

But it can just as easily accommodate five without any impact on sound quality since any input not being listened to is completely disconnected from the circuit. The third single-ended connection can serve as home-theater pass-through with a simple change in the setup menu [creating the fixed output Frederic missed but unless a single source has twinned outputs, it does require reformatting that convertible input - Ed].

I think I say it about each piece of Esoteric of equipment coming through the house but built quality is simply exceptional. Actually, the C03 feels even more impressive than previous Esoterics, being heavier even than the Musical Fidelity A5 integrated amplifier and on the scale beating all other preamplifiers in house by a factor of at least two (the VRE-1's total weight came close but it has an external power transformer so the impression of material density is not quite as striking). Weight is not the only sign of built excellence however as the controls are smooth yet offer just the right amount of resistance to provide perfect tactile feedback. No over-shooting the desired input, no struggle to reach it either. The photos should reassure anyone in doubt that the internal construction received the same attention to detail as did external cosmetics and features. This machine truly is built like a tank to last a lifetime and more.

Yet the most interesting feature of the C03 has to be its 0/+12dB gain setting*, allowing the listener to choose not only the best gain structure but also audibly influence the overall character of the preamplifier. With a volume control ranging from -99dB to 0 in 1dB and then 0.5dB steps coupled to the input-specific +/-18dB trim feature, proper gain already is very easily set with the C03. What the main gain option adds is a way to fine-tune the overall gestalt not unlike bias settings found on some tube and solid-state amplifiers but more subtle in effect.


* I distinctly remember just having the 12dB gain option from my first go-around with the C03 as Frederic described it. Yet the unit I purchased in March of 2009 offers not only 0 and 12dB but also 24dB as shown. This enhances the gain flexibility and voicing options yet further. It's like rolling three different brands of the same tube - Ed.