Parasound Halo A21+ Stereo Power Amplifier

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*300 watts RMS x 2, 8 Ohms
*500 watts RMS x2, 4 Ohms
*1000 watts x1, 8 Ohms, Bridged mode
*Circuitry designed by legendary John Curl
*High bias Class A/AB operation
*Balanced inputs of discrete circuits and XLR connectors
*Direct Coupled for cleanest signal
*MOSFET driver stage and JFET input stage, hand-matched
*60 amperes peak current per channel

  • Circuitry designed by legendary John Curl
  • High bias Class A/AB operation
  • 60 amperes peak current per channel
  • Stable with speaker impedance dips to 1.5 Ω
  • Balanced inputs with discrete circuits and XLR connectors
  • CHK Infinium, custom 5-way speaker binding posts
  • Gold-plated RCA input & loop output jacks
  • Direct Coupled – no capacitors or inductors in signal path
  • Hand-matched MOSFET driver stage and JFET input stage
  • Full power is rated all the way down to 5Hz for unrestricted low-end bass
  • AC turn-on inrush surge protection with relay bypass
  • JFET input stage, MOSFET driver stage
  • 16 beta-matched 15 amp, 60 MHz bipolar output transistors
  • 1.3 kVA encapsulated toroid power transformer with independent secondary windings for each channel
  • Independent power supplies for input stage, driver stage and output stage
  • 108,000 μF power supply filter capacitance
  • Harris hyper-fast soft-recovery bridge diode rectifiers
  • DC Servo and relay protection circuits
  • Automatic turn-on by 12 V trigger or audio sensing
  • 4 rack space chassis with rear carry handles
  • Rack mount hardware is included

Changes from the original A 21→A 21+

  • 250 → 300 Watts (8Ω)
  • 400 → 500 Watts (4Ω)
  • 750 → 1000 Watts (bridged)
  • Filter cap: 88,000 uF → 108,000 uF
  • S/N: 112dB → 115 dB
  • THD (at full power): 0.2% → 0.1%
  • Crosstalk (20kHz): 63dB → 70dB
  • Transformer size: 1.2 kVA → 1.3 kVA
  • Weight: 60 LB → 71 LB
  • Refined Halo cosmetic with aluminum end caps & gold highlights
  • Updated rear panel with heavy duty speaker terminals from JC 5
  • Upgraded internal gold on gold audio connections
  • Updated auto turn on circuit

Continuous power output:  Full audio band (20 Hz – 20 kHz) Stereo Mode (0.1% THD)
300 watts RMS x 2, 8 Ω, both channels driven

500 watts RMS x 2, 4 Ω, both channels driven

1000 watts x 1, 8 Ω, Bridged Mode (0.1% THD)

Current capacity:
60 amperes peak per channel

Power bandwidth:
5 Hz – 100 kHz, +0/-3 dB
20 Hz – 20 kHz, +0/-0.25 dB

Total harmonic distortion:
< 0.01 % at full power
< 0.03 % at typical listening levels

IM distortion: balanced 16 V rms
< 0.04 %

Interchannel crosstalk:
> 80 dB at 1 kHz;
> 70 dB at 20 kHz

Input sensitivity:
1 V for 28.28 V

Input impedance:
33 k Ω unbalanced; 66 k Ω balanced

S/N ratio:
> 115 dB, input shorted, IHF A-weighted
> 110 dB, input shorted, unweighted

Damping factor:
> 1100 at 20 Hz

Dimensions:
W448 x D508 x H197, (H181 without feet) mm

Net weight: 71 lb. (32.2 kg)

http://www.parasound.com/a21+.php

Stereophile March 2020

“The new Parasound A 21+ was impossible to fault… remarkably powerful, transparent and quiet. Anyone in the market for a stereo power amp would be well advised to consider the Parasound A 21+, especially those who believe that they must spend more.”

Home Theater Review Feb 2020

“With its high-quality chassis, thoughtful circuit design, and excellent sound quality, the A 21+ offers an impressive value proposition. Those shopping for a stereo amplifier in this price range should give the A 21+ serious consideration.”

Positive Feedback January 2019

“The A 21+ represents a new unparalleled value in amplifier performance. Details like soundstage depth, focus, and texture is where the A 21+ puts real distance from the A 21. The A 21+ is exceptional and provided an awe-striking feel.”

 

Price:  RM19,300

2 Years local warranty.