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For immediate release:

Parasound’s Halo Amps Glow at 250W for 2-, 5-, or 7-Channels
Matched Two- and Five-Channel Amplifiers can be combined for Big, Powerful Audio Systems

The Halo A 51 Power Amplifier

Las Vegas (1/08/03) – Parasound is powering up its premium Halo line with matched five- and two-channel THX Ultra2-certified power amplifiers, each rated at 250 watts per channel. The five-channel Halo A 51 and two-channel A 21 were created by Parasound’s legendary designer, John Curl. Each has a massive power supply, direct-coupled topology, professional-style balanced inputs with XLR jacks, JFET inputs, MOSFET drivers, high-current bi-polar output transistors, and outstanding build-quality topped off by the Halo line's stunning silver faceplate and accent trim.

The Halo A 51 and A 21 feature 164,000 and 100,000 microfarads of main filtering respectively, easily satisfying any instantaneous transient peak demands. Eight beta-matched 15 amp, 60 Mhz bipolar devices are used at the output stage of each channel, delivering 250 Watts RMS per channel into 8-Ohm loads, and 400 Watts per channel with 4-Ohm loads. The A 21 can also be bridged to deliver 750 Watts RMS into 8 Ohms.

The Halo A 51 and A 21 are designed for high quality reproduction of stereo or multichannel audio, and are perfectly suited for use together in a high-power 7.1-channel home theater system. Each amplifier uses pure Class A discrete component hand-matched JFET input stages, MOSFET driver stages for a warm, tube-like sound bipolar output stages rated at 60 peak amps per channel. They operate in class A at all but the most stringent transient listening levels, and are direct-coupled from input to output, eliminating the signal degradation that is caused by having reactive elements such as inductors or capacitors in the signal path.

There are rear-panel XLR and RCA inputs, RCA loop outputs (A 21 only), robust 24 kt gold-plated five-way binding posts, and 12V DC trigger connections. Other features include an illuminated power button and logo badge, auto turn-on by audio signal with adjustable sensitivity, and a ground-lift switch to eliminate the hum that is often a problem in rack-mount installations. Each model includes rear carry handles and rack mount brackets for mounting in a 4u rack space; each has relay protection circuits, a thermal overload indicator, and status indicators for each channel. Operating voltages are 110-120 V or 220-260V.

The Halo by Parasound A 51 and A 21 are now available with suggested retail prices of $4,000 and $2,000 respectively.

Parasound introduced the Halo brand in 2002 as a performance- and design-conscious step-up from the company’s traditional product line. Founded in 1981, Parasound Products, Inc., is a privately owned U.S. company that specializes in providing affordable audio and home theater components to the critical listener. For more information and dealer locations, visit or call 415 397-7100.

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Halo A 51

Halo A 21






Press Contact:

Gordon Sell   

908 788-0700


Gordon Sell
Public Relations

Parasound Products, Inc.
McKinnon Ave.
San Francisco CA   94124

(415) 397-7100

Gordon Sell Public Relations
63 Main Street
Flemington, NJ 08822

(908) 788-0700