Esoteric Grandioso C1X line preamplifier

Even as I was admiring some of the handsomest audio gear I'd ever set eyes on, my thoughts kept returning to equipment of a very different sort.

Flash back maybe 40 years to my one-bedroom apartment on Elgin Park in San Francisco during the period when I was whistling for my supper and performing Puccini's "O mio babbino caro" in the Emmy-nominated Peanuts cartoon, "She's a Good Skate, Charlie Brown." Cue the constant din of an elevated four-lane freeway, since demolished as a blight on humankind, which I tried to pretend was the sound of water in the accompaniment to one of Schubert's many "water and fish" songs.

Enter a reporter from the College of Marin newspaper, poised to write a preview of my forthcoming performance at his school. As he set foot in my living room, his eyes turned toward what I affectionately called my "Home Entertainment System": a carefully arranged, multilevel array of cardboard boxes that held my LP collection and books, with openings in which nestled two nondescript speakers, what may have been a Pioneer or Dual 1019 turntable, and a mass-market receiver. I was quite proud of that setup, which to me looked rather cool in its own starving-artist way.

Forward one week to how crushed I felt when I saw that his preview led off with a hurtful reference to a living room "dominated by an antiquated stereo system held up by dilapidated cardboard boxes." What to me was my only possession of infinite worth was to him a dismissible relic of a life he hoped to leave far behind.

He wouldn't have written those words had he cast his eyes upon the sculpted lines and understated, brushed-silver finish of the two-piece Esoteric Grandioso C1X preamplifier ($45,000). When tastefully illumined by its adjustable blue LED lighting, the Grandioso C1X's power supply looks like a million dollars—which, given its healthy price tag, it should. Its preamp section reminds me of the front of a sports car—a fancy one that leaves my repainted '94 Corolla looking as déclassé as my home entertainment system did back then. Looking at Esoteric's bathed-in-blue baby every time I enter my music room makes me feel good.

Is this audiophile jewelry? Here, I feel compelled to quote my dearly departed New York Jewish mother, who quipped during one of our last visits in Margate, Florida (footnote 1): "The older we get, the more jewelry we wear." To answer a question with another question: If something sounds as good as it looks, and someone can afford to make it their own, what's the problem?

Cost doesn't seem to be a chief concern to Esoteric customers, the majority of whom, historically, have bought the company's most expensive products in a given line, including during this pandemic year.


A book and its cover
Esoteric, a subsidiary of the TEAC Corporation, certainly wants you to feel that the Grandioso Series C1X is worthy of possession. In an extended Zoom interview with Keith Haas, national sales manager of Esoteric's US distributor, Onkyo USA (footnote 2); Hiroyuki Machida, general manager of Esoteric Marketing and Sales; and Shota Terai, Esoteric digital marketing/social media guru, Machida-san pointed to the fine lines on the face of the power supply and preamp units. Slowly carved into a heavy aluminum plate with a three-dimensional cutter, each line retains its integrity as the panel narrows and the lines grow closer. This doesn't affect the preamp's sound, but it does affect the perception of value (footnote 3).

The design goal was "to create the best preamp ever made," Machida-san said of this two-unit dual mono preamplifier, whose outboard power supply requires two 15-amp power cables. "According to our engineers, 70% of sound quality is determined by the power supply," he said. "It's like a power amplifier that drives speakers, and it has enormous headroom." At 64lb, the power supply is the heaviest part of the C1X and consumes about 20W. The power supply connects to the preamp via two supplied umbilical cables that are approximately 44.5" long. Separating the units prevents any transformer vibration from affecting sensitive preamp circuitry.

"Musical expression was most important. We wanted more natural and open sound across the range. We thought the C1, which sounded very clear with a very smooth midrange, was the best preamp ever made when we introduced it in 2014, but over time our engineers thought the bass was slightly exaggerated. Now the bass extension is much deeper, but it's not a bass-heavy sound. We wanted a more natural, open-sounding preamp." One of the ways Esoteric achieved this goal was by securing the preamp's two amplifier modules—there's one per channel—with hooks rather than screws. Using hooks allows for some internal movement and contributes to more open sound.


The externals of the new C1X preamp are almost the same as those of its C1 predecessor, but the layout inside is entirely new. "We like to keep the appearance of our top-line products consistent for a long time," Machida-san explained. "For example, Porsche didn't change its external design for many years, and Rolex didn't change its watch design for over 60 years, even as the insides changed. But most audio manufacturers change their designs frequently, which decreases value. We like to retain the same design for a long time to increase value for our customers. The C1X's aesthetic also matches the M1 monoblock and other products in the Grandioso series."

The C1X repositions two of the preamp's four proprietary adjustable feet, and those feet are now mounted differently to deliver sound that is airier and more open. To enhance air, the top covers of both the power and preamp units are loosely mounted in semifloating fashion rather than screwed on tight. The volume knob's edge was changed "for a more elegant look," and the display uses a larger font. I had no trouble seeing input choice and volume from 12' away.

Internal changes are numerous. One is Esoteric's new "Ultra Fidelity Attenuator System," an integrated stepped-resistor attenuator that uses two integrated chipsets and proprietary circuitry designed in-house. Claimed to eliminate the crosstalk and uneven channel level balance that Esoteric says afflict variable-resistor attenuators, Esoteric's UFA promises shorter signal paths, longer service life, and freedom from noise. To ensure a smooth volume curve, which is not guaranteed with stepped resistors, the company developed what they claimed to be an "arguably perfect" stepped-resistor attenuator system with 1120 precise 0.1dB steps, which is effectively continuous. The attenuator in the C1X's predecessor, the C1, had 100 0.5dB steps.


The location of the preamp's transformer has changed from the center of the main panel to a separate, lower panel that's separated by plates to prevent vibration leakage. Capacitors, which also vibrate, are separated as well (footnote 4).

The fully balanced input section uses a new, FET-based input selector claimed to prevent sonic coloration from mechanical relay parts. Polarity-inversion circuits have been eliminated in order to get the signal more directly to the output amplifier. The power supply, designed for dual AC in/dual DC out, includes five transformers: one each for the input and output section for each channel and a separate transformer for the logic-control section. New to the power supply box are low-feedback, discrete DC regulators, chosen for their more natural, live sound, and dual-layered parts placement for better resonance control. Other new features include a switchable Line/AV passthrough on all input terminals, RS232 C system control trigger functions, a ±18dB input gain trim that's adjustable in 0.1dB steps, a ±6dB balance control adjustable in 0.1dB steps, and large display fonts.

"Our preamplifier module uses its own integrated chipset," Machida-san told me. "The sound of our Integrated Discrete Amplifier Module (IDM-01) is better than a discrete design's because the signal paths in our circuit layout are very short and produce faster and more natural sound."

What you see, what you get, what I did
The Grandioso C1X preamplifier's numerous features also include dimmable/extinguishable front-panel illumination, mute, input naming, ESL-A link connectivity (for compatible Esoteric products only), and a new, easy-to-hold-and-use remote control. There are so many more features that if I attempt to mention them all, there won't be room to discuss the preamp's sound. Suffice to say that Esoteric has striven to create an ultimate, state-of-the-art product with up-to-date features; those features are discussed in detail online here. There, you can also find the clear, complete manual, a print copy of which you'll find in the box with the preamp.


The power supply's front panel is a thing of beauty, especially when its LED power indicator is turned up and the panel's sculpted lines are bathed in blue. The standby/on button is so positioned that you may not even notice it. The rear panel is, of course, more utilitarian, with IEC jacks for each of the two 15A power cables, two outputs for the supplied pliant umbilical cords that connect the power supply to the preamp, two trigger outputs, a signal ground connector for optional use with an SACD/CD player or amplifier, and front-panel LED illumination adjustment.


The volume and input knobs on the preamp's front panel are both large and smooth-turning, and the display is easily readable from 12' away. You can choose to surround the knobs always with blue light, have the blue illumination appear briefly when you adjust volume or change inputs, or turn it off entirely. While I loved to gaze at the power supply's blue illumination, the blue around the main preamp's control knobs did not match the blue readout of its display; I set it to illuminate briefly when I adjusted volume or settings. The rear panel features two pairs of RCA inputs, three pairs of XLR/ESL-A inputs (footnote 5), two pairs of XLR outputs, two pairs of ESL-A outputs, two inputs for the DC umbilical cords, trigger input, a micro-USB port (for software updates), RS-232C (for system integration), and signal ground connections.

Footnote 1: My mother followed the 11th Commandment: Thou shalt retire to Florida.

Footnote 2: As this review was being edited, 11 Trading Company—the distribution arm of the company that owns Klipsch—announced that it was taking over distribution of Esoteric and TEAC, and that Haas would join 11 Trading as national sales manager for the two brands. So, despite these changes, Haas's position remains much the same as before.

Footnote 3: For your daily dose of audio porn, head here.

Footnote 4: Terai-san, who also goes by the name Sean, referred me to this Japanese-language YouTube video that shows the preamp's interior.

Footnote 5: ESL-A is Esoteric's proprietary interconnect scheme.

Esoteric Company
US Distribution: 11 Trading Co.
3502 Woodview Trace #200
Indianapolis, IN 46268
(949) 374-4487

Axiom05's picture

Give me a break, $45K for a preamp and only a 3 year warranty. Bryston gives 20 years and Simaudio gives 10 years. Why don't manufacturers show that they have some faith in their products? Oh, I guess I answered my own question.

Ortofan's picture

... mechanical parts, such as a laser transport, volume control and/or switches.

georgehifi's picture

With todays sources having digital volume controls, and output stages very well capable of driving most amps, and more than enough gain to send those amps into clipping.
This is a review of a very expensive switch box.
Because of it's 12db output gain stage, it has to throw away most of the sources output voltage!! (sacrilege), so then it's 12db gain stage can boost it back up again noise, distortion and all.
Doesn't make sense any more to have them. It's just a very expensive switch box that adds noise and distortion, than if you went direct.

Cheers George

PeterG's picture

Although many excellent sources do have their own volume controls, and their well respected manufacturers agree that you do not need a preamp, I cannot remember a review of any of those sources that did not note they they sounded better with a pre amp in the system.

jgossman's picture

The issue is the sense of VOLUME. You can spin a pin wheel with an air compressor, lots of voltage, but never feel the cool air. Now think of a brisk wind on a summer day, you can feel it. The pin wheel (measuring device) doesn't know any difference, but you know the difference. That's the difference in a unit with 1-3 volts of output and a digital volume vs a 10 or 20 volt output POTENTIAL. It's the sense that the music never runs out of steam.

ejlif's picture

Yin and yang that is how you sum up the comparison to the D'agastino preamp? You also reviewed the AR preamp and didn't really commit to how it sounds to the Rossini direct. Inquiring minds want to know So the preamps are complete polar opposites? Hard to really decipher what is meant by that whole jumble of words in the comparison section. Esoteric Rolex, D'gastino greta garbo concealed as her name is bathed in blue on Sunset Blvd. WTF?

windansea's picture

i concur

That Other Guy's picture

I find the styling atrocious.

windansea's picture

and the marketing seems to focus more on the exterior looks rather than the underwhelming PCB innards

rwwear's picture

I'm sure it sounds great but blue displays are so nineties. And it's rather ugly IMO.

ACranston's picture

Based on JVS's comments that this preamp revealed information from well-known recordings that he had not noticed before, I would guess that this preamp is even more revealing than the D'Agostino HD. It would seem that this preamp highlights detail where you notice the individual trees more than the forest where the D'Agostino highlights the opposite. Regardless, I would love to hear it.

georgehifi's picture

"I cannot remember a review of any of those sources that did not note they they sounded better with a pre amp in the system."

Or worse!!

It hardly ever gets A/B'd and commented on, when available.

Cheers George

AnalogueFan's picture

"the component that delivers a lifetime of joy and pleasure."

It is something difficult, if the Warranty they give is so short, a few Years of Warranty vs. High price is strange.

At least I wouldn't try a Japanese preamp, at any price, because I had a phono one and it was a disaster, to be honest.

Thanks for the candid report: "The C1X speaks in ways that only the finest components can."

Andrei's picture

JVS 'analysis' seems empty. There is nothing to change my opinion against several other low noise pre-amps.