Parasound JC1+ Mono Power Amplifiers - Pair

Description

MY TAKE: For more than twenty years Parasound has been a name synonymous with unequaled value. Their electronics are respected for both performance and reliability and compete with significantly more expensive products. Modestly priced, previous offerings have changed the common perception about the level of performance that can be achieved at the price point. With the introduction of the Halo line, Parasound looks to bring the same level of value and performance to a more upscale market.

For a number of years, the legendary John Curl has worked with Parasound as a consultant. His input has greatly influenced their products and is one of the reasons for the praise they’ve received from the audiophile community. Several seasons ago Parasound again enlisted the services of Mr. Curl and his team, CTC Builders, to design the highest-quality power amplifier ever made. The result is the JC 1+, manufactured exclusively by Parasound.

The JC 1+ is among the most transparent, dynamic, and sonically neutral solid-state amplifiers available. Its design sophistication, quality of parts, and superb construction make the JC 1 and exceptional value. - Galen Carol

REVIEWS:
 

Tone Audio: Close as it gets to having and eating your cake

"While we rarely if ever throw that big “b-word” around, the Parasound JC 1+ monoblocks are pretty damn incredible, ticking all the boxes for an incredibly reasonable price. In my travels, I’ve met a number of audiophiles that have to have the most expensive components money can buy, regardless of cost. These are the people you see with $500k to sky’s the limit systems. As Jerry Seinfeld used to say, “not like there’s anything wrong with that.”

"However, I have met a number of music lovers that have experienced those systems, and while equally passionate, would love a system in the $100k – $200k range offering as much of the sonic benefits that these no holds barred systems render, but with more realistic budgets. If you are someone with this priority list, and want solid-state amplification, the JC 1+ monos should be at the top of your list. I have yet to hear a pair of solid-state amplifiers that offer anywhere near this much sonic excellence and sheer power for anywhere near the asking price of these amplifiers. Should you be on the way up in your audiophile journey, assembling a mega but sensibly priced system, these could also be your first major anchor as you build that system. With this much power on tap, you certainly won’t have any limits with your speaker choices.

"Finally, one other aspect of these amplifiers that rarely gets mentioned in the context of a hifi review is long term value and durability. I’ve never seen a complaint about Parasound on the internet anywhere. In a world where all the internet pundits complain about everything on a regular basis, I looked for a few days to see if anyone had any kind of problems with Parasound, either in terms of disappointment with the purchase, to lack of support, or problems with repairs. For that matter, I couldn’t find a single horror story about a Parasound product croaking, anywhere. And I have my share of horror stories about a few brands that cost 2-5x what these amplifiers do, that took months (and in one instance years) to be repaired. Parasound’s stellar reputation for build quality should weigh heavily into your matrix when thinking about dropping this kind of cash.

"These are fantastic amplifiers. That’s why they are staying, making them worthy of two of our awards, the #toneaudioapproved award, and our Exceptional Value Award.

"I can’t suggest these highly enough." - Jeff Dorgay
Full Review

Tone Audio: - Prelimary assessment: "These are some pretty incredible amplifiers.While Parasound has raised the price substantialy, they’ve done a complete makover on them, and of course we’ve got a pair of originals to compare.The original JC1was a groundbreaking high power/high quality amplifier at an incrediblylow price,but theJC1+is the same.

"If this amplifier had a botique-y badge on the front panel, you’d pay $50k and be bragging about them tomorrow on social media. That’s why at $17k/pair, they are the big amplifier deal of altime.

"Full report soon, but it didn’ttake much seat time to make the call on these." - Jeff Dorgay

Stereophile: "With JC 1+ amplifiers, the feeling of listening to a Steinway D in a real space was very satisfying. High frequencies were smooth and clean, more like what I experience from a good tube amplifier. Dynamics were extraordinary. Low-frequency power and delicacy! The improvement in its sound quality and the recent explosion of the prices of high-end, high-power amplifiers keep the JC 1+ competitive. This is a superb-sounding amplifier that will get the best from every loudspeaker with which it is partnered. Well done, Mr. Curl."

"The original JC 1 amplifiers were superb amplifiers. Five years in the making, the JC1+ is a complete redesign by John Curl, the JC1+. This is a remarkable amplifier!" - John Atkinson
 

Home Theater HiFi: "One of the most important of the Parasound’s capabilities is in dynamics. Its very high power (450 watts into 8 ohms) delivers a tremendous dynamic range. So, it is not just the ability to drive any speaker on the planet. It will allow very quiet passages and very loud passages as well, without having to change the volume control.

"The Parasound JC 1+ Power Amplifiers are very high quality. One would expect that from the almost $17,000/pair price, but high price is no guarantee of quality for any product. It has to be verified. Proof of Performance for the Parasound has been verified. They are worth the price." - John E. Johnson
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Positive Feedback: "The JC 1+ is a stirring achievement, and not just "for the price," that simply demands your consideration.

"I've not heard any other monoblock entrant at or even close to this price that is able to recreate so many aspects of music with a more authentic voice. These amps are magnificent performers in nearly every regard. Honestly, I cannot think of a pair of monoblocks that offer a view anywhere near this close to the top of the heap for anywhere near their asking price. I can tell you that if I were shopping for a pair of monoblocks under $25,000, the Parasound Halo JC 1+ would be my first choice. Go give these new over-achievers a listen and be prepared to be bowled over by what you will hear. Most enthusiastically recommended." - Greg Weaver
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Stereophile Recommended Components 2021 - "A replacement for the long-term "Recommended Components" resident, the original Halo JC 1, the 1+ represents designer John Curl's further thoughts on this powerful solid-state monster. While more expensive in real terms than its predecessor, the Halo JC 1+ is 30% heavier, still heavily biased into class-A, and offers slightly more power than the original amplifier: 450W into 8 ohms, 850W into 4 ohms, and 1300W into 2 ohms. Bass guitar and kickdrum were reproduced with appropriate force and definition, felt JA, exclaiming, "Low-frequency power and delicacy!" JA was also impressed by the pair of monoblocks' ability to differentiate soundstage depth and described the Parasound's high frequencies as sounding "more like what I experience from a good tube amplifier." "This is a superb-sounding amplifier that will get the best from every loudspeaker with which it is partnered," JA concluded, adding "Well done, Mr. Curl." On the test bench, the Halo JC 1+ exceeded its specified power into 8 ohms, clipping at 500W. It didn't quite meet its specified power into lower impedances, clipping at 830W into 4 ohms and at 1200W into 2 ohms, though JA did note that the slight shortfall was due to him not holding the AC wall voltage constant in the testing. Commendably, the JC 1+'s distortion was predominantly the subjectively innocuous second harmonic, though at a very low level." -  (Vol.43 Nos.6 & 7)

Changes from the JC 1 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 → 2.1 kVA
• 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 of gain
• R-core power transformer for the 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 circuits with 3.5mm 12V trigger jack

All Features:

• Filter capacitance: 132,000 → 198,000 uF
• Transformer capacity: 1.9 → 2.1 kVA
• 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 of gain
• R-core power transformer for the input stage
• The 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 circuits with 3.5mm 12V trigger jacks
• 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 the 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 the power line
• 6 massive 33,000 uF Nichicon Gold Tune filter capacitors for the 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 amperes, 230V, 60 MHz bipolar output transistors
• 2.1 kVA shielded toroid power transformer with premium H18 grade core
• Independent power supplies for the 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

Specifications:
 

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

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

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
2 Hz - 120 kHz, +0/-2 dB
20 Hz - 20 kHz, +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 kΩ
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 28.28 V Output into 8 Ω
Unbalanced: 1 V
Balanced: 1 V per leg
(Gain switch set to normal)

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
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)

Shipping Carton Dimensions
Width: 29-1/2" (750 mm)
Depth: 27-1/2" (700 mm)
Height: 15-3/4" (400 mm)

Net Weight
83 lb. (37.6 kg)

Shipping Weight
107 lb. (48.5 kg)

Power Requirement
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