Parasound Halo Series JC-5 Power Amplifier

 Designed to deliver plenty of power

Parasound's 73-pound JC 5 delivers a whopping 400 watts per channel, and it's stable enough to drive just about any speakers you might care to hook up. In bridged mode, this amp really turns on the juice, putting out an amazing 1,200 watts into a single channel. All that power comes from a beefy toroidal transformer and a high-bias Class A/AB amplifier design that help your system reproduce music with stunning clarity and accuracy. The "JC" designation — and the signature on the front and back panels — lets you know it was designed by the company's audio design guru John Curl (more on him later). 

Class A/AB operation for smoother sound

You don't see a Class A/AB amplifier every day, so let's break down the benefits.

Engineers and audiophiles generally agree that Class A designs offer the purest sound, but they tend to run hot and take up a lot of space. As a result, home audio amplifiers often use a compromise known as Class AB, which hands off part of the audio signal to a different set of output transistors at high power levels. AB can sacrifice a bit of signal purity, but it lets the amp run cooler and more efficiently.

So this Class A/AB amp operates in pure Class A mode up to a higher power level than most other amplifiers in its price category, before the second set of transistors kick in. The result is a sound that's smoother, less fatiguing, and more natural.

Convenient connections

On the back panel are balanced XLR and unbalanced RCA inputs for each channel, and each has its own individual gain control knob and loop output. There are also binding posts for connecting a pair of speakers. The amp can be rack mounted using the included ears.

The legacy of John Curl

The Halo JC 5 features circuitry designed by John Curl, a legend in audio engineering. He started his career in the 1970s, designing tape and video recorders at Ampex, and he had a hand in building the Grateful Dead's famous Wall of Sound. Curl has worked with Parasound since 1989, designing all of their high-power amplifiers and more. The power supply, transistors, capacitors and other parts in the JC 5 were chosen to offer uncompromising audiophile-grade performance.

Product highlights:

• 400 watts per channel into 8 ohms (20-20,000 Hz) at 0.05% THD with 2 channels driven
• 600 watts x 2 into 4 ohms
• 1,200 watts x 1 at 8 ohms in bridged mode
• bridged operation at 4 ohms is not recommended
• designed by legendary audio engineer John Curl
• high-bias Class A/AB amplifier design
• large custom toroidal transformer
• frequency response: 5-100,000 Hz (-3dB)
• signal-to-noise ratio: 116 dB
• left and right balanced XLR and unbalanced RCA inputs
• individual gain control for each channel
• RCA loop outputs for each channel
• let you daisy-chain additional amps
• in bi-amp configuration, passes input signal from one channel to the other's RCA input
• custom 5-way binding post speaker connectors
• in bridged mode, only the positive binding posts are used
• switchable turn-on options: manual, signal sensing, or 12-volt trigger
• detachable power cord
• rack mounting ears included

Dimensions and warranty:

• 17-5/8"W x 7-3/4"H x 21-1/2"D (4U rack spaces)
• weight: 73 lbs.
• warranty: 5 years
• MFR # JC 5 BLACK

Features & specs

Product Research

Features

Stereo Power Amplifier: The Parasound HALO Series JC 5 is an ultra-high performance Class A/AB, stereo power amplifier. The JC 5 is built to extremely strict quality and performance standards for which Parasound is renowned. Every part within the JC 5 has been carefully chosen for its accuracy, sound quality and long life. The Halo Series JC 5 stereo amplifier is profoundly powerful and supremely musical.

• 8-Ohm: 400 watts x 2 @ 20-20kHz with 0.05% THD (both channels driven)
• 4-Ohm: 600 watts x 2 @ 20-20kHz with 0.05% THD (both channels driven)

Bridge Mode: Bridged operation configures the Left and Right channels to function as a single channel higher power amplifier to drive a single speaker. When a JC 5 is in Bridged Mode it provides far greater power output than the sum of its left and right channels’ power output. Please note that in bridged operation the minimum speaker impedance is 8 ohms (not 4 ohms). The JC 5 is rated at 1200 watts x 1 @ 20-20kHz (8-ohm) in bridged mode.

Note: See Owner's Guide for speaker wire connection and configuration in Bridged Mode.

Separate Input Stage Power Supply: Power amplifiers must eliminate input stage distortion in order to avoid output stage distortion which is especially irritating to a listener. In typical power amplifiers the input and output stages share the same power supply. When driven hard their output stages’ voltage will sag, dragging down the input stage voltage that’s critical for preventing these distortions. A signature feature of the JC 5 is a separate independent input stage power supply for each channel that is always 10 volts higher than the output stage voltage. Maintaining input stage voltage prevents distortion even under the most demanding conditions.

High Current Output: High current is essential for uncompromised sound. The JC 5 output (current) stage uses 24 Sanken 15A output transistors, carefully hand-matched for maximum performance. Their 60MHz bandwidth eliminates slew-rate distortion that robs music of its nuances. They operate in pure Class A up to 12 watts per channel, eliminating distortion that blurs music at lower listening levels. Eliminating noise at the input stage is also critical. The JC 5 uses rare Toshiba 2SJ74 J-FETs which are highly coveted for their ultra-low noise.

Balanced & Unbalanced Analog Inputs: The Parasound HALO Series JC 5 is outfitted with both balanced stereo XLR and unbalanced stereo RCA analog inputs. In most systems balanced XLR connections will give you the best sound. Using balanced XLR input connectors results in a 6 dB higher volume level compared with using the RCA input jacks.

Note: The Balanced/Unbalanced switch is not an input selector. Its function is to optimize the signal to noise ratio for each type of input. You should not connect both the Balanced and Unbalanced jacks at the same time with the expectation of switching between two different devices such as a preamp and surround processor.

Loop Output Jacks: These stereo RCA jacks enable the incoming audio signal to pass along or "daisy-chain" from the Left and Right Input jacks to an additional amplifier or powered subwoofer. The Loop Out jacks are not affected by the volume control settings. The Loop output jacks work with either the balanced XLR or unbalanced RCA inputs.

24K Gold-Plated Binding Posts: The Halo Series JC 5's speaker terminals are new, developed in collaboration with CHK. Their ample size and wide spacing accommodates even the largest gauge speaker wire, spade connector, and banana plugs (single only). High quality 24 K gold-plating on the speaker terminals, input connectors and internal audio signal connections assure sound quality that won't be compromised by corrosion.

Detachable AC Power Cord: The AC cord supplied with the JC 5 is a high quality IEC type cord. Please connect it directly to an AC wall outlet or power conditioner that is always on. If possible, plug your JC 5 into the same AC outlet that your preamplifier is plugged into. If different AC outlets are used for the JC 5 and other components, (including a TV or video projector) the ground potential may be higher or lower between the outlets, resulting in audible hum.

Turn-On Options: The Turn On Options switch on the back-panel determines how the amplifier turns on and off. Setting the Turn On Options switch to Audio or 12 V disables the JC 5's front-panel Power button. There are 3 positions for this switch - Manual, Audio, or 12V Trigger.

• Manual: When the Turn On Options switch is set to Manual, the JC 5 is turned on and off manually only by pressing the Power button on its front-panel every time you want to listen to music.
• Audio: When the Turn On Options switch is set to the Audio position, the JC 5 will be turned on automatically when an audio signal is present at the L or R Input jacks. After the audio signal ceases the amplifier will remain on for about 10 minutes before shutting itself off. This prevents unintended turn-off during pauses in your music.
• 12V Trigger: When the Turn On Options switch is set to its 12V position, the JC 5 is turned on and off only with an external +9 V to +12V DC voltage, using its 12V Trigger input (3.5mm). When the external voltage ceases the amp will turn off within a few seconds. The 12V turn on trigger circuit in the JC 5 requires a mere 5mA from the 12V trigger source.

12V Loop Out Jack: The 12V Trigger Out jack (3.5mm) lets you loop or "daisy-chain" the incoming trigger voltage to an additional JC 5 or other component(s). The total load on your triggering device's 12V output is the sum of the trigger current drawn by each of the components you plan to loop together. Check the maximum capacity of your preamplifier's trigger output so you do not overload it by connecting too many power amplifiers. Typical triggering devices are rated to handle 50mA to 100mA.

Rack Mountable: The JC 5 features a 4 rack space chassis with rear carry handles. Rack mounting hardware is included.

High-Temp Indicator: The front-panel High-Temp indicator will glow red if any channel overheats. The On-Off button will also glow red if the JC 5 overheats. If such a condition occurs you must provide for better ventilation around the amplifier or check speakers for faulty operation that is causing the JC 5 to overheat.