PRE-OWNED MOON 700i Integrated Amplifier (SN: M7616377)

The 700i - part of Simaudio's top-of-the-line Moon Evolution series - is a fully differential dual-mono design that pumps 175Wpc into 8 ohms or 350Wpc into 4 ohms. The 700i runs in class-A up to 5W, and in class-A/B thereafter. Its output stages are powered by six bipolar transistors per channel, manufactured and matched to extremely high standards (claims the company's "white paper") for "exceptional gain-linearity," wider bandwidth, and a lower noise floor. Circuits are DC-coupled, which reportedly allows for a flat frequency response throughout, as well as below and beyond, the entire audioband. The 700i's "zero global feedback" design—which Simaudio's Lionel Goodfield, defines as "zero feedback except for just a little bit, locally, at the output stages only"—eliminates the need for signal correction, thus boosting the speed of the signal response, reducing phase errors and tonal colorations, and all but wiping out intermodulation distortion. Individual output devices are decoupled from one another, which is said to expand the power reserves of each, to produce a more effortlessly dynamic sound.

The circuit board has four layers of pure copper tracings—two for the audio signals, one each for the ground and power supplies—which makes possible very short signal paths and low levels of noise. The preamp section is mounted on its own dedicated circuit board, reducing crosstalk. The two very heavy toroidal transformers are precisely rolled from very-high-grade Japanese steel, designed in a proprietary process called Vacuum Pressure Impregnation, which is said to bolster the core's resistance to mechanical vibrations. The chassis—sleek with rounded edges, and remarkably compact for its 60 lbs—is made of thick, ultrarigid aluminum. Small, very sharp thumbscrew cones protrude from four wedge-like pillars to further reduce the effects of vibrations.

This pre-owned amplifier has recently been refurbished with new capacitors on the output board and is fully up to date (2017) with the recommended MOON updates. The amplifier is in fully working and very good cosmetic condition.