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Parasound - HALO A21+ - Power Amplifier
Parasound - HALO A21+ - Power Amplifier
Parasound - HALO A21+ - Power Amplifier
Parasound - HALO A21+ - Power Amplifier
Parasound - HALO A21+ - Power Amplifier

Parasound

Parasound - HALO A21+ - Power Amplifier

$7,999.00

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Unit 9/20 Rivergate Place, Murarrie, Qld 4172 Get directions
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Overview

HALO A21+

Brand
Parasound
Category
Power Amplifiers
SKU
HALO-A21+

Not sure it's the right fit for your room or system? Our team can talk you through it.

Call 1300 308 711
Our thoughts

Direct coupling with no capacitors or inductors in the signal path sets the Halo apart, suiting owners who want as little reactive hardware between source and speakers as possible. Two channels of 300 watts into 8 Ω give demanding loudspeakers a generous reserve.

Stability into impedance dips down to 1.5 Ω means speakers with demanding loads sit within the amplifier's design envelope. Balanced XLR and unbalanced RCA inputs with A/B speaker terminals suit mixed systems and two pairs of loudspeakers. Bridged mode gives a single 1000 watt channel, though bridged operation into 4 Ω is not recommended. Automatic turn-on by trigger or audio sensing lets it switch on with the rest of your system.

This suits owners with demanding loudspeakers or a large room who want a substantial amplifier with flexible connections. Speaker load and preamplifier connection are the decisions to raise with our team, so call or drop in to talk it through.

The Audio Tailor team, Murarrie showroom

The Halo A 21+ power amplifier is a pinnacle of power and fidelity

The Parasound Halo A 21+ has two channels providing 250 watts per channel into 8 Ω, it delivers breathtaking audio performance. The high bias Class A/AB operation ensures accurate and detailed sound reproduction, while the stable operation into 2 Ω loads allows for versatility in speaker configurations. The direct-coupled design, free from capacitors in the signal path, preserves signal integrity and enhances transparency. With balanced XLR and unbalanced RCA inputs and A/B speaker terminals, it offers flexibility and compatibility. Experience pure power and fidelity with the Halo A 21+ power amplifier.

Parasound HALO A21+ features

  • 300 watts x 2 @ 8 Ω RMS, both channels driven
  • 500 watts x 2 @ 4 Ω RMS, both channels driven
  • 1000 watts x 1 @ 8 Ω, in bridged mode
  • 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
  • CHK Infinium, custom 5-way speaker binding posts
  • Gold-plated RCA input & loop output jacks
  • Direct-coupled signal path, no capacitors or inductors
  • DC Servo and relay protection circuits
  • AC turn-on inrush surge protection with relay bypass
  • JFET input stage, MOSFET driver stage
  • 16 beta-matched 15 ampere, 60 MHz bipolar output transistors
  • 1.3 kVA shielded toroid transformer w/ independent windings for each channel
  • Independent power supplies for input stage, driver stage and output stage
  • 108,000 µF filter capacitors for output stages
  • Full power is rated all the way down to 5Hz for unrestricted low-end bass
  • Harris hyper-fast soft-recovery bridge diode rectifiers
  • Automatic turn-on by 12 V trigger or audio sensing
  • 4 rack space chassis with rear carry handles
  • Rack mount hardware is included

Specifications

Technical details

Manufacturer specifications. Want to know how it compares with something else? Ask our team.

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 aluminium 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
Power Output – Stereo Mode (0.1% THD)300 watts x 2, 8 Ω both channels driven, 500 watts x 2, 4 Ω both channels driven
Power Output – Bridged Mode (0.1% THD)1000 watts x 1, 8 Ω, Bridged 4 Ω operation is not recommended
Power measurements are at 120 VAC0.1% THD, RMS continuous power, full audio band (20 Hz - 20 kHz)
Current Capacity60 amps peak, per channel
Slew Rate> 130 volts per microsecond
Frequency Response5 Hz - 100 kHz, +0/-3 dB, 20 Hz - 20 kHz, +0/-0.25 dB
Total Harmonic Distortion (THD)< 0.1 % at full power, < 0.03 % at typical listening levels
IM Distortion< 0.04 %
TIMUnmeasurable
Inter-channel Crosstalk> 80 dB at 1 kHz, > 70 dB at 20 kHz
Input ImpedanceUnbalanced: 33 kΩ, Balanced: 66 kΩ,(33 kΩ per leg)
Total Gain29 dB
Input Sensitivity for 28.28 V Output into 8 ΩUnbalanced: 1 V, Balanced: 1 V per leg
S/N Ratio> 115 dB, input shorted, IHF A-weighted, > 110 dB, input shorted, unweighted
Damping Factor> 1100 at 20 Hz
DC Trigger Requirements+9 Vdc to +12 Vdc, 5 mA
Audio Trigger Requirements2 mV - 10 mV
XLR Pin Identification1 = Ground (Shield), 2 = Positive, 3 = Negative (Return)
DimensionsWidth: 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 Weight71 lb. (32.2 kg)
Power RequirementStandby: 1 Watt, Idle (no music playing): 160 Watts, Typical Listening levels: 300 Watts, Maximum: 1400 Watts

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