Parasound Halo A 52+ Multi-channel Power Amp

Description

The Parasound Halo A 52+ is a high-performance five-channel power amplifier designed to bring audiophile-grade sound quality to both music and home theater systems. Introduced as the successor to the highly regarded Halo A 52, the A 52+ incorporates refinements derived from Parasound’s flagship Halo A 51 while retaining a more compact chassis and lower price. Designed by legendary engineer John Curl, whose resume includes products for Mark Levinson, Vendetta Research, and CTC Builders, the amplifier combines massive current capability, exceptionally low distortion, and robust build quality with the smooth, musical character that has made Parasound’s Halo Series a favorite among enthusiasts.

At the heart of the A 52+ is a high-bias Class A/AB design that operates in Class A for low-level signals before transitioning seamlessly into Class AB as power demands increase. A custom 1.5 kVA encapsulated toroidal transformer, independent secondary windings for each channel, and an impressive 100,000 µF of filter capacitance provide the substantial power reserves needed to reproduce demanding movie soundtracks and dynamic musical passages without strain. The amplifier is conservatively rated at 180 watts per channel into 8 ohms with all five channels driven simultaneously, increasing to 255 watts per channel into 4 ohms, while two-channel operation delivers up to 225 watts into 8 ohms and 350 watts into 4 ohms.

The Halo A 52+ is engineered to remain stable with difficult loudspeaker loads and is capable of delivering peak currents of 45 amperes per channel. Its direct-coupled circuitry eliminates capacitors and inductors from the audio path, preserving signal purity, while carefully matched JFET input devices, MOSFET drivers, and high-current bipolar output transistors contribute to exceptional transparency and control. Whether driving efficient bookshelf speakers or demanding floorstanders, the amplifier maintains excellent composure, producing authoritative bass, effortless dynamics, and an expansive, well-focused soundstage.

Professional reviewers have consistently praised the amplifier’s performance. Sound & Vision noted that the Halo A 52+ “delivers clear, dynamic sound and has plenty of headroom to handle the explosive effects in movie soundtracks,” highlighting its ability to remain composed even during the most demanding multichannel passages.

Stereophile reviewer Kalman Rubinson was equally impressed, concluding simply, “Overall, I really liked Parasound’s Halo A 52+ in every way.” The review praised the amplifier’s effortless presentation, refined sonic character, and ability to reproduce both music and movie soundtracks with authority and realism while avoiding the harshness or fatigue sometimes associated with high-powered solid-state amplifiers.

Connectivity is equally comprehensive. Each channel includes both balanced XLR and unbalanced RCA inputs, allowing easy integration with premium surround processors and AV receivers. Automatic turn-on can be triggered either by a 12-volt input or by sensing an incoming audio signal, making installation straightforward in virtually any system. Heavy-duty five-way binding posts accommodate a wide variety of speaker cables and connectors.

The Parasound Halo A 52+ represents the philosophy that has long defined the Halo Series: deliver reference-quality engineering and musical performance without the extravagant pricing often associated with boutique high-end audio. Whether used in a premium home theater or a multichannel music system, it provides the power, refinement, and reliability expected from one of the industry’s most respected amplifier designers.

Product Specifications

• Amplifier Type: Five-channel Class A/AB power amplifier
• Designer: John Curl
• Power Output (All Channels Driven): 180 W x 5 into 8Ω; 255 W x 5 into 4Ω
• Power Output (2 Channels Driven): 225 W x 2 into 8Ω; 350 W x 2 into 4Ω
• Peak Current: 45 amps per channel
• Power Transformer: 1.5 kVA custom toroidal with independent secondary windings
• Power Supply Capacitance: 100,000 µF
• Frequency Response: 5 Hz–100 kHz (+0/-3 dB); 20 Hz–20 kHz (+0/-0.3 dB)
• Total Harmonic Distortion: <0.05% at full rated power
• Signal-to-Noise Ratio: >112 dB (A-weighted)
• Inputs: 5 balanced XLR, 5 unbalanced RCA
• Outputs: Five pairs of heavy-duty 24K gold-plated five-way binding posts
• Triggering: 12V trigger input/output and automatic audio-sensing power-on
• Cooling: Passive convection with large internal heat sinks
• Dimensions (W × H × D): 17.25 × 5.9 × 20 in. (437 × 149 × 508 mm)
• Weight: 55 lbs. (25 kg.)