PCM1792A DAC Card for E7 only

Warm, rich, high-resolution sound thanks to the flagship Texas Instruments (formerly Burr-Brown) DAC
This is a replacement DAC card for the E7 series, featuring two Texas Instruments "PCM1792A" DACs in a left/right independent configuration. The PCM1792A, a representative flagship DAC lauded by TI alongside AKM and ADI during the golden age of ΔΣ DACs, has been adopted in numerous masterpieces for its smooth and realistic sound. To unleash the true potential of the PCM1792A, which is designed for high-voltage operation in stationary devices, in portable equipment, LE OS's precise control and an asymmetrical power supply design, born from the conclusion that "higher numerical values do not always guarantee the reproduction of musical essence," are employed.

■ Tuning focused on emotional reproduction rather than numerical characteristics of the PCM1792A
Instead of optimizing the output voltage, the load balance in the signal path and the bias points of the transistors are intentionally adjusted, and slight nonlinear components are utilized to fine-tune the harmonic composition and transient characteristics. The "soft sound grains" and "melting mid-high range" unique to the PCM1792A are achieved by exploring the optimal balance between power supply voltage suitable for portable devices and sound quality. This design has been further improved from a prototype that achieved a dynamic range of 125dB with ±5.8V for the I/V stage and 5.2Vrms output. A re-engineered power architecture, without compromise, simultaneously achieves a dynamic range of 123dB and 4.7Vrms output, realizing musical richness and supple texture.

■ AsymPower Control for both musical bliss and portability
By individually optimizing the ± current response of each circuit block and precisely controlling the operating current and time response, subtle offsets in transistor operating points and matching of power supply impedance organize the harmonic composition, bringing out the soft yet solid resonance inherent in the PCM1792A. While typical symmetrical power supply configurations prioritize theoretical values from simulations and power efficiency, AsymPower Control overcomes the technical challenges specific to asymmetrical power supply configurations. It suppresses heat generation, voltage drop, and loss of minute signals often seen in high-voltage DACs, maximizing the chip's potential and achieving a high level of both stability and efficiency as a portable device.

■ The sweet resonance of music played by past masterpieces isn't always best represented by measured values
The PCM1792A DAC card prioritizes musical consistency, such as melodic coherence, sustained harmonics, and spatial depth, over peak measured values. The sound produced by the PCM1792A exists in a realm different from numerical measurements. The richness of the mid-high range, the slight elasticity of the low end, and the smooth lingering reverberation throughout the sound field. This is the result of electrical harmony generated by a design that optimizes linear characteristics to the extreme and the precision of the analog stage's power supply. The change from 125dB to 123dB is not a decrease in specifications, but an intentional adjustment to reach the optimal auditory solution, and without betraying the musical reproduction accuracy consistently pursued by the E7 series, its sweet sound coexists analog comfort within digital precision.

■ High quality equivalent to balanced connection even with single-ended output
While conventional DAPs tend to have circuit structures where single-ended output performance is modest, this module fully utilizes all output channels of the two PCM1792A DACs, with all circuits such as IV conversion, LPF, volume control, and buffer amplifiers fully operational. Even the 3.5mm single-ended terminal achieves uncompromising playback in terms of information density, localization, and dynamics.

■ EA4-specific line output design
Leveraging the experience from the popular limited edition "P6Pro10th Limited," a dedicated line output circuit optimized for the EA4 amplifier is employed. By switching with the regular LO, the matching between E7 and EA4 is optimized. This achieves a high level of both sound richness and delicacy, and soundstage expression.

*Accessories and some specifications may be subject to change without notice due to firmware updates.
*This product is for the DAC card only. It can be used with either the E7 4497 PREMIUM or E7 4497 STANDARD, updated to the latest FW.
[Please note that it may not be recognized depending on the FW version.]
(AD1955 DAC card recognition is supported with firmware v1.1.6 or later)