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For immediate release:

Parasound Debuts 400-Watt Monoblock Amplifier Designed by John Curl

More photos of the Halo by Parasound JC1 at the end of this release


For designer comments on the engineering behind the Halo JC1, click here

San Francisco, 8/27/02 -- Parasound has introduced its highly-anticipated 400-watt JC 1 monoblock power amplifier as the flagship amplifier for its new Halo line of premium audio components.With nearly inexhaustible current reserves, the amplifier easily delivers 800 Watts into 4 Ohms, and 1200 Watts into 2 Ohm loads. This extremely powerful and uncompromising component was developed by Parasound in collaboration with legendary designer John Curl’s CTC Builders, and represents the culmination of 13 years of Curl's ongoing evolution of Parasound power amplifier topologies.

“The combination of Parasound’s ability to manufacture very high quality components, and John Curl’s remarkable design, makes this one of the finest amplifiers ever built at any price,” said Parasound’s president, Richard Schram. “The sound quality and power capabilities of this amplifier are breathtaking.”

Formed in 1998, CTC Builders consists of John Curl handling electrical design, board and layout design by Carl Thompson, and Bob Crump's component selection and implementation. The trio has developed a number of products, including the CTC Blowtorch preamplifier and the CTC BBQ amplifier, that have received the utmost respect and accolades from the most discerning audiophiles and high-end magazine reviewers.

The JC 1 was conceived as a signature product, growing out of CTC's modifications of the Parasound HCA 3500 amplifier which was sold between 1999 and 2001. With various changes to the design, including a much larger heatsink and double the power supply, as well as component and layout alterations, the monoblock JC 1 is unmatched by anything at its $3,500 price, and will stand up favorably to any component available at any price.

The heart of the JC 1 power supply is a large toroid transformer rated at 10 Amperes continuous, backed up with four enormous 33,000-microFarad Nichicon Gold Tune electrolytic filter capacitors, which Curl believes to be the finest in the world. The tremendous inrush of current required to charge 132,000 microFarads of capacitance requires a specially designed relay-bypassed "soft start" circuit to prevent tripped circuit breakers. Through meticulous board design and component placement, as well as massive aluminum heatsink, the amplifier operates without the need for unnecessary cooling fans.

Curl's complementary JFET and MOSFET configuration for the input and driver stages respectively provide pure class A operation in these parts of the circuitry. Nine pairs of high current bipolar transistors in the output stage provide up to 25 Watts of pure Class A -- more than that of amplifiers selling for several times the price of the JC 1. Only during extremely loud musical passages or large bass transients, such as special effects 'explosions,' does the JC 1 enter Class AB operation.

The JC 1 power amplifier features the stunning silver cabinetry common to the entire Halo by Parasound line. The JC 1 is currently available at a suggested retail price of $3,500 each.

Halo by Parasound was introduced 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.

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Parasound JC 1 Specifications


RMS Power, 20 Hz - 20 kHz
400 watts continuous, 8 Ohms
800 watts continuous, 4 Ohms
1200 watts short term, 2 Ohms
Class A Power, 20 Hz - 20 kHz
25 watts, bias set to high, 8 Ohms
10 watts, bias set to low, 8 Ohms
Current Capacity
135 amperes peak
Slew Rate
> 130 V/µsecond
Frequency Response
2 Hz - 120 kHz, +0/-3 dB
Total Harmonic Distortion
< 0.15 % at full power
< 0.018 % typical levels
IM Distortion
< 0.03 %
Dynamic Headroom
> 1.8 dB
Input Impedance
Balanced - 100 k Ohms
Unbalanced - 50 k Ohms
Input Sensitivity

Balanced - 1 V for 28.28 V output into 8 Ohms
Unbalanced - 1 V per leg for 28.28 V output into 8 Ohms

Signal to Noise Ratio
> 122 dB, IHF A-weighted, bias set to low
> 120 dB, IHF A-weighted, bias set to high
> 113 dB, Unweighted, bias set to low
> 111 dB, Unweighted, bias set to high
Damping Factor
> 1200 at 20 Hz
DC Trigger Requirements
+9 Vdc to +12 Vdc, 2 mA
Audio Trigger Requirements
50-250 mV AC
DC Trigger Output Capacity
+12 Vdc, 150 mA
Total Width: 17-3/4” (451 mm)
Panel Height: 7” (178 mm)
Total Height with feet: 7-5/8” (194 mm)
Depth: 20 “ (508 mm)
Power Requirement
Idle: 250 Watts
Full Power into 4 Ohms: 1280 Watts
Net Weight
64 lb. (29.1 kg)
Shipping Weight
79 lb. (35.9 kg)

Features and specifications subject to change without notice.

JC1 front view

JC1 rear view

JC1 side view





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