ESOTERIC has developed an original, state-of-the -art transmission format called ES-LINK4, which allows DSD and 352.8kHz/48bit PCM ultrawideband digital transmission using an HDMI cable. ES-LINK4 performs a large part of the digital signal processing on the sending side, greatly reducing the digital signal processing load on the D/A converter. In addition to ultra-wide bandwidth, we sought high sound quality through our “Pure D/A” concept, in which the D/A converter specializes in its original function of D/A conversion processing.

The D1 applies a 36-bit D/A processing algorithm that converts PCM signals to analog signals at a high resolution of 36 bits by combining several 32-bit DAC devices. The tone of the high-bit data is used for faithful analog conversion. The resolution of 32-bit encoding is 256 times higher than that of 24-bit encoding, and 36-bit encoding gives an amazing resolution level that is another 16 times higher – a total of 4,096 times higher than the resolution of 24-bit encoding. Producing even finer bit tones minimizes operational error for outstanding expression of even subtle music signals.

The clock circuit, which supplies highly accurate reference clock signals to a digital circuit, can be considered the core unit of a digital player. The clock circuit of the P1 and D1 is completely independent of other circuits, including its power source and ground, enabling pure clock signals to be supplied to the system. The voltage controlled crystal oscillator (VCXO) was developed especially for the P1 and D1 in a joint effort with Nihon Dempa Kogyo (NDK), a major manufacturer of crystal oscillators. For a high-precision custom clock device worthy of leading models, high sound quality playback is provided thanks to an extremely low level of phase noise and a crystal element that is even larger than before.

A monaural configuration for the ultimate evolutionary step toward the ideal stereo

 The D1 follows the monaural configuration of the D-01, which we introduced in 2004 as the world’s first monaural D/A converter. The D-01 was deve-loped with the goal of attaining the highest level of channel separation and the ideal power supply to each channel. In the new D1, we have introduced the latest technology and further enhanced the design. The right and left channels can now be link-connected with a single HDMI cable (provid-ed), and easy input from external source devices is possible. With the D1, you can enjoy a world of incredible stereo with the rich stereo image and sonic depth that is only possible with a monaural configuration.

Outstanding sound quality with 36-bit processing resolution

 Aiming for the pinnacle of sound quality, we have incorporated the AK4495S, a state-of-the-art 32-bit DAC device developed by Asahi Kasei Microd-evices Corporation. Sixteen circuits per channel are provided to achieve phenomenal linearity and low noise. In addition to direct processing of the DSD signal, a new 36-bit D/A processing algorithm has been adopted for analog conversion of the PCM signal at 36-bit resolution. The result is fine, smooth sound quality as along with high resolution.

ESOTERIC-HCLD*: ESOTERIC’s own output buffer circuit featuring fortified current transmission

 A high-speed current transmission capability is the most important factor of an analog output circuit for transmitting a wide dynamic range of music signals downstream without deficiencies. For the ultimate performance as a line driver, the output buffer amplifier circuit of the D1 makes extensive use of materials and is configured with its own board separate from the D/A converter. The curr-ent output capability is high, and the high-perfor-mance elements adopted for the slew rate, which indicates response speed, boast the incredibly high speed of 2000V/μs. The ability to supply instant current is maximized with an extravagant buffer circuit configuration utilizing one circuit for RCA output and one circuit each for hot and cold conn-ections for XLR output. With the ESOTERIC-HCLD, the D1 reproduces the dynamism of music with breathtaking reality.
*HCLD=High Current Line Driver

High sound quality through the separation of digital and analog circuits

 All analog circuits (DAC circuit analog portion, HCLD buffer circuit, etc.) are electrically separate from the digital circuits. This further enhances the clarity of sound quality by preventing the intrusion of digital noise.

Large toroidal transformers boasting high speed and surplus power supply capacity

 Two large toroidal power supply units are installed for the digital and analog circuits, enabling high-efficiency and high-power drive operation in add-ition to low noise and low distortion. Stable and clean power is supplied to each circuit block by strong power supply circuits incorporating multiple large capacitors.

Seven types and eight channels of digital input that support high sampling rates

 To enable connection to an extensive range of devices, the D1 is equipped with wide-ranging dig-ital inputs of seven types and eight channels (ES-LINK x 1, XLR x 1, iLINK 4p/6p x 1, USB x 1, coaxial x 2, optical x 1), and can be used for high-sampling -rate sources of up to 24-bit/192kHz. In addition, XLR x 2 supports high-sampling-rate/high-bit inp-uts of 48-bit/192kHz (ES-LINK3) and 24-bit/384 kHz (Dual AES 8Fs).