Parasound JC1+ Monoblock Amplifier

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

Features:

• Changes from the JC1 to JC 1+

  • 400 -> 450 Watts @ 8Ω
  • 800 -> 850 Watts @ 4Ω
  • 1200 -> 1300 Watts @ 2Ω
  • Filter capacitance: 132,000 -> 198,000 uF
  • Transformer capacity: 1.9 -> 2.1kVA
  • Output transistors: 18 -> 24 Sanken 60Mz devices
  • Peak current: 135 -> 180 amps
  • Weight: 64 -> 83 lbs net
  • Bybee Music Rails™ active high frequency noise filters
  • John Curl driver stage employs a new cascode circuit design
  • FR-408 input circuit board material improves HF signal integrity
  • Gain switch to select 29 dB or 23 dB gain
  • R-core power transformer for input stage
  • Input circuit board is shielded
  • Double thickness copper on output/power supply circuit boards
  • Gold-plated internal audio signal path connectors
  • Custom CHK Infinium speaker binding posts
  • Looping Neutrik XLR output for easier bi-amping
  • Front panel power indicator LED
  • Updated auto turn on circuit with5mm 12V trigger jacks

  All Features:

  • Circuitry designed by legendary John Curl
  • Ultra-high bias Class A/AB operation
  • 25 watts of pure Class A power
  • Stable with speaker impedance dips below 1Ω
  • Bybee Music Rails™ - active high frequency filters for input stage
  • New John Curl driver stage employs a cascode circuit for greater open loop bandwidth & superior linearity
  • Gain switch to select 29 dB or 23 dB gain for optimum compatibility with high gain preamps or extremely efficient speakers
  • R-core transformer for input stage suppresses noise on power line
  • 6 massive 33,000 uF Nichicon Gold Tune filter capacitors for output stage
  • 22,400 uF input stage power supply filter capacitors, independent of the main power supply
  • Dual CHK Infinium, custom 5-way speaker binding posts for easy bi-wiring
  • Neutrik locking XLR balanced input & loop output jacks
  • Vampire 24k gold-plated RCA input & loop output jacks
  • Direct-coupled signal path, no capacitors or inductors in the audio path
  • JFET input stage, MOSFET driver stage
  • 24 beta-matched 15 ampere, 230V, 60 MHz bipolar output transistors
  • 2.1 kVA shielded toroid power transformer with premium H18 grade core
  • Independent power supplies for input stage, driver stage & output stage
  • Full power is rated all the way down to 2Hz for unrestricted low-end bass
  • Harris hyper-fast soft-recovery bridge diode rectifiers
  • REL & Nichicon Muse capacitors
  • DC servo & relay protection circuits
  • AC turn-on inrush surge protection with relay bypass
  • Automatic turn-on by 12 V trigger or audio sensing
  • 4 rack space chassis with rear carry handles
  • Rack mount hardware is included
  • Available in silver or black