Grandioso C1 Line Stage Preamplifier

    The Overview

    Sound, in the form of music has tremendous power to move our emotions.
    In music, the absence of sound can be as powerful as sound itself.
    By skillfully combining knowledge, technology and materials,
    we can create audio components that is capable of generating these same strong emotions.
    Then, in blissful communion with the music,
    the listener is able to forget the very existence of the audio system.
    Placing its prestige on the line,
    ESOTERIC proudly introduces an outstanding
    new preamplifier: Grandioso C1.

    The Grandioso C1 is the result of the dedication to audio quality instilled in every component that bears the proud Grandioso name. Advancing well beyond the core objective of creating “high fidelity,” in the development of the new C1 we set our sights on new summits, blending the sensibilities of the audio engineer with those of the consummate musician.

    A product of uncompromising craftsmanship and the highest standards of audio fidelity, each C1 preamplifier is handmade in our Tokyo factory and fully reflects Esoteric’s underlying Grandioso philosophy. State-of-the-art circuit design and leading-edge technology combine to realize outstanding audio performance. The C1’s robust construction employs two separate chassis, with each channel totally independent from the other.

The Features

Massive Construction


 The C1’s two-chassis construction physically isolates the power supply from the audio circuitry. This allows the unit to create a sound stage having exceptional transparency, as well as providing a liberating sense of musical vibrancy, without betraying so much as a hint of stress.
 The C1’s separate 29kg linear power supply enables pristinely accurate amplification and ensures that the music signal is delivered to the power amplifiers without any loss of dynamics. This gives the music the power and vibrancy to captivate the listener. Due to the C1’s monoblock internal construction, all the elements of each channel are completely independent: from the audio circuitry to the DC power supplies, and right down to the separate AC power cables. Creating the excitement of having every musical instrument accurately positioned before you, the C1 is the crystallization of an approach single-mindedly focused on accurate stereo sound reproduction.

DC Power Supply Unit


 The C1’s DC power supply features a fully independent two-channel design with dual AC inputs and DC outputs. Together with the careful selection of components one would expect in such a reference product, this produces significant improvements in sound quality. Especially notable in the power supply’s construction is the use of five generously rated power transformers, high-capacity reservoir capacitors and silicon carbide (SiC) Schottky barrier diodes.

Precision Controls Offer Outstanding Operational Feel


 The C1’s input selector and volume knobs are machined from solid blocks of aluminum. The use of a VRDS drive mechanism bearing system for the control shafts enables silkily smooth rotation with absolutely no mechanical play in their movements. Rotational torque has also been fine-tuned to provide the luxurious feel of a precision analog control, in keeping with this top-of-the-line preamplifier.

Ultra–Low-Noise Logic Control


 The logic control section is built into the front panel and is totally isolated, both physically and electronically, from the preamplifier module by the use of an optocoupler. The logic control further ensures low-noise operation by completely shutting down when not in actual operation, totally eliminating any possible influence on the C1’s audio circuitry.

Circuit Design

 All sections of the amplification circuitry are fully balanced, with the input buffer, volume control and high-speed output buffer laid out three-dimensionally to achieve the shortest possible signal paths. The C1’s DC power supply provides a clean and stable output to each preamplification section, ensuring that the power amplifiers maintain full control of the loudspeakers, while at the same time preserving the music’s delicacy and dynamics.

Advanced Output Buffer Circuitry Delivers Stronger Performance to Drive Power Amplifiers —ESOTERIC-HCLD*


 In its function as a line driver, the preamplifier must have the ability to fully drive the power amplifiers in a way that faithfully conveys music signals that have an extremely wide dynamic range, extending all the way from pianissimo to fortissimo. The key to achieving this is having a circuit with both a high current drive capability and high speed. The C1’s output buffer circuitry utilizes high-performance components to deliver a very high level of current drive, together with an exceptionally high slew rate of 2,000V/μs. Each output has its own independent drive circuit, and for the XLR outputs, the instantaneous output current capability is maximized by the use of fully symmetrical circuitry for both the hot and cold phases.
 The C1 employs an EDLC* Super Capacitor array located close to the output buffer circuitry to function as a highly stable power source. Its compact physical size belies the fact that it provides the extraordinary capacity of 100,000μF (0.1F) for each channel, facilitating very high levels of instantaneous output power, which in turn provides strong and solid bass reproduction. With the integration of these two technologies, the C1 recreates a breathtaking level of audio reality by preserving the musical dynamics that would otherwise be lost if smaller current transmission levels were employed between the preamplifier and power amplifiers.

The Specs

Speaker Outputs
Rated output power STEREO 200 W + 200 W (8 Ω)
400 W + 400 W (4 Ω)
BTL BTL 800 W (8 Ω)
Maximum output power STEREO 250 W + 250 W (8 Ω) (JEITA)
500 W + 500 W (4 Ω) (JEITA)
BTL 1,000 W (8 Ω) (JEITA)
Frequency response 5 Hz ~ 100 kHz (1 W, 8 Ω, ±1 dB)
Signal-to-noise ratio (S/N) 117 dB or more (JEITA)
Total harmonic distortion 0.009 %
(1 kHz, 8 Ω, Rated output power)
Minimum required impedance STEREO 4 Ω / BTL 4 Ω
Gain 28 dB
Analog audio inputs
Jacks RCA jacks 1 stereo
XLR jacks 1 stereo
Input impedance RCA 150 kΩ / XLR 320 kΩ
Power supply AC 230V 50Hz
AC 120V 60Hz
AC 220V 60Hz
Power consumption 550 W
External dimensions (W x H x D) 445 x 220 x 430 mm
(17 1/2" x 8 5/8" x 16 15/16" )
(including protrusions)
Weight 41.2 kg (91.5 lb)
- Design and specifications are subject to change without notice.
- This product is available in three different power supply variations shown in the chart above. Make sure that the voltage shown on the rear panel matches the AC line voltage in your area.
- The shape of the AC inlet and plug of the supplied power cord depends on the voltage rating and destination country.