Preamplifier MOON by Simaudio 850P 2-Tone

MOON 850P — reference analogue preamplifier with dual-chassis construction and a fully isolated audio section

The MOON 850P is Simaudio's flagship analogue preamplifier, built around a dual-chassis construction in which the audio section is rigorously separated from both the power supply and the control electronics. One chassis houses the power supply, digital control circuitry, software processing and LED display, the other exclusively the audio circuits. This division minimises the influence of interference from the digital and power sections on the sensitive signal path and contributes to exceptional transfer accuracy.

Supply voltage stabilisation employs i2DCf (Independent Inductive DC Filtering) technology — a separate choke is assigned to every integrated circuit in the signal path, 40 stages in total. The design is complemented by a suspended chassis that counters microphony, reducing the transmission of vibration into the active circuitry. The result is an extremely low noise floor, with a 130 dB signal-to-noise ratio at full output and THD of 0.0005 %.

A frequency response of 5 Hz – 100 kHz ±0.1 dB, crosstalk of −130 dB at 1 kHz and an output impedance of 50 Ω define a component that imposes no character of its own on the signal. In practice this means legible microdetail, precise placement of instruments across the stereo stage and dynamics free of compression — the preamplifier sonically "disappears", leaving room for the recording and the connected power amplifier.

Connectivity comprises 3 pairs of XLR and 5 pairs of RCA inputs with an input impedance of 11,000 Ω and sensitivity of 200 mV – 4.0 V RMS, with every line input offering gain offset adjustment of ±10 dB and configuration for home theatre mode with the volume control bypassed. Outputs consist of 2 pairs of XLR and 2 pairs of RCA (fixed and variable). The package includes the FRM-3 remote control, colour-coded interconnecting cables between the chassis, a SimLink cable and a mains cable.

Key features

• Dual-chassis construction: Audio circuits completely separated from the power supply
• i2DCf filtering: A dedicated choke for 40 stages of the signal path
• Anti-microphony suspension: Suppression of vibration transmitted into the circuitry
• 130 dB signal-to-noise ratio: THD 0.0005 %, crosstalk −130 dB at 1 kHz
• Flexible inputs: 3× XLR and 5× RCA, gain offset ±10 dB