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Parasound Halo A21+ Stereo Power Amplifier B-Stock

UPC: 791084202038
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Original price $2,995.00
Current price $2,649.00

SKU A21+BlackB
Color: Black

Product Qualifies for FREE Ground Shipping

PARASOUND B-STOCK
  • 100% WORKING CONDITION
  • THOROUGHLY INSPECTED
  • ORIGINAL PACKAGING + ALL ACCESSORIES
  • FULL MANUFACTURER'S WARRANTY
  • Parasound Halo A21+ Stereo Power Amplifier B-Stock Full Warranty


    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

    All 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
      • Available in silver or black
    Specs
    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 measurement are at 120 VAC:
    0.1% THD, RMS continuous power,
    full audio band (20 Hz - 20 kHz)

    Current Capacity
    60 amps peak, per channel

    Slew Rate
    > 130 volts per microsecond

    Frequency Response
    5 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 %

    TIM
    Unmeasurable

    Inter-channel Crosstalk
    > 80 dB at 1 kHz
    > 70 dB at 20 kHz

    Input Impedance
    Unbalanced: 33 kΩ
    Balanced: 66 kΩ,(33 kΩ per leg)

    Total Gain
    29 dB

    Input Sensitivity for 28.28 V Output into 8 Ω
    Unbalanced: 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 Requirements
    2 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
    71 lb. (32.2 kg)

    Shipping Weight
    88 lb. (39.9 kg)

    Power Requirement
    Standby: 1 Watt
    Idle (no music playing): 160 Watts
    Typical Listening levels: 300 Watts
    Maximum: 1400 Watts