Parasound Halo JC 1+ Jr. Mono Power Amplifier By John Curl

JC1+ — Extreme Power, Extraordinary Finesse

The Parasound JC1+ delivers monoblock performance on a majestic scale—450 W into 8 Ω, over 1,300 W into 2 Ω, and up to 25 W in pure Class A. Whether it’s the intimate tones of solo piano or the thunder of orchestral crescendos, the JC1+ delivers every detail with uncanny control, space, and realism.

Built on John Curl’s decades-long halo legacy, this amp raises the bar with rugged R-core power supply design, system tuning switches, and precision-grade audio components. Its transparent performance and refined execution make it ideal for high-resolution systems, audiophile-level home theaters, and demanding speaker pairings alike.

Praised by listeners and reviewers:

• “It sounds like it’s not even trying—just clean, open power.”
• “The JC1+ brought out new life in my speakers—I didn’t know they had it in them.”
• “Holographic sound. The amp disappears and the music just fills the room.”

Awards & Recognition

• Stereophile – Recommended Component (2024)
• Secrets of Home Theater & High Fidelity – Best Monoblock Power Amplifier (2020)
• TONEaudio – Exceptional Value Award (2020)

Specifications: 

Power Output: 450 x1 watts @ 8Ω, 850 x1 watts @ 4 Ω, 1300 x1 watts @ 2 Ω

Power measurements are with 120VAC: 0.15% THD, RMS continuous power,full audio band (20Hz - 20kHz)

Class A Power Output: 25 Watts bias switch set to high, 10 Watts bias switch set to low

Current Capacity: 180 amps, peak

Slew Rate: > 130 volts per microsecond

Frequency Response: 2Hz-120 kHz +0/-2 dB, 20Hz-20kHz, +0/-0.25 dB

Total Harmonic Distortion (THD): < 0.15 % at full power, < 0.02 % at typical listening levels

IM Distortion: < 0.03 %

TIM: Unmeasurable

Damping Factor: > 1200 at 20 Hz

Input Impedance: Unbalanced: 50 kΩm Balanced: 100 kΩ, (50 kΩ per leg)

S/N Ratio, inputs shorted

• >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

Total Gain: 29 dB (Gain switch set to normal), 23 dB (Gain switch set to low)

Input Sensitivity for 28.28V Output into 8Ω (Gain switch set to normal)

• Unbalanced: 1 V
• Balanced: 1 V per leg

DC Trigger Requirements: +9 Vdc to +12 Vdc, 5 mA

Audio Trigger Requirement: 2.5 mV - 10 mV

XLR Pin Identification: 1 = Ground (Shield), 2 = Positive, 3 = Negative (Return)

Dimensions

• Width: 17-5⁄8" (448 mm)
• Height without feet: 7-1⁄8" (181 mm)
• Height with feet: 7-3/4" " (197 mm)
• Depth: 20" (508 mm)
• Depth with cables: 21-1⁄2" (546 mm)

Net Weight: 83 lb. (37.6 kg)

Shipping Weight:  107 lb. (45.4 kg)

Power Requirements

• Standby: <1 Watt
• Idle (bias set to low): 145 Watts
• Idle (bias set to high): 275 Watts
• Typical Listening levels: 400 Watts
• Maximum: 1500 Watts