The Moon by Simaudio 681 is a reference-grade digital audio source component engineered for listeners who demand absolute purity, precision, and refinement from their systems. Designed with Simaudio’s cutting-edge digital architecture, the 681 serves as a remarkably transparent link in any high-end audio chain, delivering exceptional resolution and ultra-low distortion across the full frequency spectrum. With its expansive dynamic range and astonishingly low noise floor, it opens a window into recordings with clarity and dimensionality that feels effortless and natural. The unit’s ultra-precise clocking, robust power supply regulation, and meticulous internal layout ensure that digital signals are handled with absolute integrity. Its frequency response extends from 2 Hz to 100 kHz, allowing playback with remarkable openness, while the incredibly low THD+N and IMD figures preserve the micro-details that give music texture and realism. The adjustable output levels offer system-matching flexibility, ensuring optimal performance with a wide range of preamps and integrated amplifiers. Even in demanding setups, the 681 maintains composure through a combination of noise-rejection design and ultra-low crosstalk. Compact yet substantial in build, the Moon 681 is engineered to deliver state-of-the-art transparency and musicality while maintaining efficient power consumption across multiple standby modes.