MOON 330A Power Amplifier The MOON 330A Power Amplifier is a high-performance stereo power amp built to bring effortless drive, control, and realism to your system—without sacrificing refinement. Designed as the stereo counterpart to MOON’s 400M monoblocks, the 330A pairs balanced differential, dual-mono architecture with proprietary MOON Bipolar output devices for speed, grip, and clean authority across the full frequency range. Bass lands with weight and articulation, while vocals and cymbals hang in space with natural air and ambience—exactly the kind of separation and ease that elevates great speakers and high-resolution sources. Beyond the sound, the 330A is built for serious systems and long-term reliability: it’s engineered for low distortion, wide bandwidth, and stable performance, with custom-install friendliness via 12V trigger and RS-232 control. Whether you run balanced XLR from a preamp, use RCA single-ended, or bridge it to create a powerful mono amplifier, the MOON 330A is a future-proof foundation for an audiophile-grade setup. The Moon 330A is part of ListenUp's Moon Power Amplifier Collection. What It's Good At: Delivering tight, authoritative bass with excellent control and musical drive Creating an airy, stable soundstage where vocals and cymbals “float” naturally Driving demanding speakers confidently with 125W/ch (8Ω) and 250W/ch (4Ω) power Preserving detail and dynamics with balanced differential, dual-mono amplification Supporting custom installs with 12V trigger in/out and RS-232 connectivity Scaling with your system—run stereo now, bridge to 400W mono later MOON 330A Full Specifications: Product type: Stereo power amplifier Configuration: Balanced differential, stereo (dual-mono design) Class of operation: A/AB (Class A output to 5 watts) Output device type: Proprietary MOON Bipolar Output power @ 8Ω: 125 W per channel Output power @ 4Ω: 250 W per channel Output power (bridged mono) @ 8Ω: 400 W Gain: 31 dB Input sensitivity: 800 mV RMS Input impedance: 47,500 Ω Frequency response (full range): 10 Hz – 125 kHz (+0 / -3 dB) Signal-to-noise ratio: 100 dB @ full power Total harmonic distortion (20 Hz–20 kHz @ 1 W): 0.02% Total harmonic distortion (20 Hz–20 kHz @ 125 W): 0.05% Intermodulation distortion: 0.02% Power supply transformer: 400 VA (custom proprietary toroidal transformer design) Power supply capacitance: 85,000 µF High damping factor: Yes (yields superior dynamics, improved signal speed & refined timbre accuracy) Power consumption @ idle: 36 W AC power requirements: 120 V / 60 Hz or 240 V / 50 Hz Inputs: Balanced (differential) XLR input per channel; Unbalanced (single-ended) RCA input per channel Input mode note: No mode switch—operate either balanced or single-ended (one mode at a time) XLR jumper note: Factory-installed XLR “dummy” jumpers used for RCA mode; remove for balanced XLR operation Control / integration: 12V Trigger input and output (1/8” mini-jack), supports daisy-chaining; RS-232 port (DB9) for custom installation and firmware updates Speaker outputs: Two (2) pairs of heavy-duty gold-plated binding posts (left and right channels) Protection: Self-diagnostic system with automatic shutdown for DC detection or thermal protection Balanced XLR pin assignment: Pin 1 = Ground, Pin 2 = Positive, Pin 3 = Negative Fuse replacement: 120V version uses 5A fast blow (3AG); 230V version uses 3A fast blow (3AG) Dimensions (W x H x D): 16.9 x 3.5 x 14.0 in (42.9 x 8.9 x 35.6 cm) Shipping weight: 33 lb (15 kg) In the box: AC power cable; Owner’s manual; Warranty and product registration information (USA and Canada only) MOON 330A Q&A: Does the MOON 330A work best as a stereo amplifier or can it be used as mono? Yes—use it as a high-power stereo amplifier, or bridge it into mono mode for 400W into 8Ω when you want more headroom and authority. How much power does the MOON 330A deliver into 8Ω and 4Ω speakers? It provides 125W per channel into 8Ω and 250W per channel into 4Ω, offering strong current delivery and control for a wide range of loudspeakers. Can I connect both XLR and RCA sources at the same time? The amplifier supports both balanced XLR and single-ended RCA inputs, but it’s designed to operate in only one input mode at a time. What do I need to do to use the balanced XLR inputs correctly? For balanced operation, remove the factory-installed XLR “dummy” jumpers and store them safely; reinstall the jumpers if you switch back to RCA single-ended use. Is the MOON 330A suitable for custom-install or smart system integration? Yes—its 12V trigger input/output and RS-232 port make it easy to integrate into automation and multi-component power sequencing setups. What does “Class A output to 5 watts” mean in real use? It means the amplifier operates in Class A for the first 5 watts, helping low-level listening sound smoother and more immediate, then transitions to Class AB for efficient high-power performance. Should the MOON 330A be left powered on all the time? It’s designed to be powered up continuously for optimal performance, and once fully broken in, it can require several hours after powering on to reach peak sound quality. What’s included in the box with the MOON 330A? You get an AC power cable, the owner’s manual, and (in the USA/Canada) warranty and product registration information. MOON 330A Downloads: MOON 330A ManualMOON Power Amplifier Comparison Chart
