Parasound Halo JC 5, Owner'S Manual

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rack mount before attaching its bolts to the equipment rack rails. These break the ground loops caused by
metal-to-metal contact between the rack, the components, and their rack-mount bolts. Extra washers are
available from any rack manufacturer
Parasound JC 5 Design Overview
Circuit Designed by John Curl
Parasound design consultant John Curl has been a legend among audiophiles and electronic engineers
for decades. He pioneered measurements to correlate musical accuracy with the materials used in parts,
worked with world-class touring companies, has designed highly coveted audio classics, including the original
Mark Levinson JC-2, Denneson JC-80, Vendetta Phono Preamplifier, and CTC Blowtorch preamplifiers;
master recorders for Wilson Audio and Mobile Fidelity; and the mixing consoles used in live concerts by The
Grateful Dead and the Montreux Jazz Festival in Switzerland.
As our featured amplifier designer since 1990, he has created many products that have earned
Parasound worldwide acclaim, including the Parasound Halo JC 1, JC 2 and JC 2 BP, JC 3, JC 3+ and JC 3
Jr.. John is particularly proud of what he and Parasound have accomplished together: “The circuits I design
for Parasound are extremely sophisticated and are typical of products that are far more expensive. I can’t
think of any other audio products that offer nearly as much bang for the buck.”
Parts Selection
Every part within the JC 5 is carefully chosen for its accuracy and reliability. Metal film resistors with 1%
tolerance are selected for their precision and because their values don’t drift as they heat up during operation.
Polypropylene and mica capacitors are used extensively for their superior linearity and low dielectric
absorption. Semiconductors are selected for superior performance in their specific roles in the circuit. Gold
has the best conductivity of any metal, so we use high quality gold-plated input connectors and speaker
terminals. The double-sided circuit boards are FR4 glass epoxy for long-term durability. The chassis is made
of heavy gauge steel to safely house the internal circuitry. This attention to detail when selecting parts makes
the difference between a very good amplifier and an outstanding amplifier.
The Power Supply
The heart of the power supply is a 1.7 kVA toroid power transformer, chosen for its efficiency, low hum
field, and high power rating. Encapsulating this massive power transformer in an epoxy-filled steel canister
assures ultra-quiet performance.
The JC 5 power transformer employs multiple independent secondary windings so that each amplifier
channel has its own power supply, assuring more than ample DC voltage at all times and under all conditions.
It also reduces inter-channel crosstalk that can blur the sound and impair the correct sense of where
instruments, dialogue and effects are positioned.
Each channel also has an independent power supply for its input stage. Their B+/B- voltage rails are even
higher than the output stage voltage rails to prevent any chance of the driver stage voltage “sagging” when
the amp is driven at high levels. This refinement greatly reduces measured and audible distortion.
Each channel’s +/- 98 Vdc output stage uses two premium quality 33,000uF Rubycon electrolytic filter
capacitors, chosen for their low Equivalent Series Resistance (ESR), dielectric absorption and resistance to
high temperature. In addition, these filter capacitors are bypassed with smaller polypropylene capacitors to
reduce AC ripple in the DC supply and to further eliminate noise and interference that is generated in AC
power lines from computers and other appliances in the home. The independent driver power supplies each
employ Nichicon Gold Tune capacitors totaling 4,440uF per channel.