Halo is Parasound’s premier line with a reputation for going head-to-head with the most expensive equipment on the market, while costing a fraction of the price. Halo has earned honors and awards that are unmatched.
Halo is Parasound’s premier line with a reputation for going head-to-head with the most expensive equipment on the market, while costing a fraction of the price. Halo has earned honors and awards that are unmatched. The Halo A 21+ is an ultra-high performance Class A/AB stereo power amplifier. We are very proud of this latest achievement of Parasound engineering in concert with legendary audio equipment designer John Curl. John Curl has been designing for Parasound since 1989. He was already a legend in the '70s for designing and building mixing consoles for The Grateful Dead and Jefferson Airplane. He has designed some of the most iconic and highest regarded audio bands in the world. Curl’s inspired designs have earned Parasound world-wide acclaim and our stunning A 21+ builds on this storied heritage.
Recording and broadcast studios use balanced connections exclusively because of their inherent ability to reject noise and hum, thus assuring the best sound. Certain high quality preamplifiers and surround controllers built for residential use utilize balanced connections with XLR jacks for the same reasons. All Parasound Halo series power amplifiers have balanced inputs with XLR jacks so you can take full advantage of their inherent noise reduction capability.
To unleash greater dynamics, the A 21+ uses four premium quality 27,000uF Rubycon electrolytic filter capacitors, chosen for their low Equivalent Series Resistance (ESR), dielectric absorption and resistance to high temperature. In addition, these filter capacitors are bypassed with smaller polypropylene capacitors to reduce AC ripple in the DC supply and to further eliminate noise and interference that is generated in AC power lines from computers and other appliances in the home.
Every part within the A 21+ is carefully chosen for its accuracy, sound quality and long life. Its speaker terminals are new, developed in collaboration with CHK. Their ample size and wide spacing accommodate even the largest gauge speaker wire or spade connectors. High quality 24 K gold-plating on the speaker terminals, input connectors and internal audio signal connections assure sound quality that won’t be compromised by corrosion.
The heart of the A 21+ power supply is a massive 1.3 kVA toroid power transformer. It is custom designed for well-contained radiated hum, high efficiency, and high power. The transformer has independent secondary windings and this provides more than ample voltage to each channel's power supply under the most strenuous operating conditions. Separate windings for each channel improves stereo imaging by reducing interchannel crosstalk and allows each channel to deliver up to 500 watts per channel at the same time.
The setting of the rear panel Turn On Options switch determines how the amplifier turns on and off. There are three options for this switch. 1) Manually by the front panel power button. 2) By connecting a 12V trigger. 3) Automatically when an audio signal is detected at the L or R Input jacks.
PARA-A21P-BL | PARA-A21P-SL |
---|---|
2-Channel |
2-Channel |
501-1000W |
501-1000W |
300W x 2, 8 Ω both channels driven |
300W x 2, 8 Ω both channels driven |
500W x 2, 4 Ω both channels driven |
500W x 2, 4 Ω both channels driven |
1000W x 1, 8 Ω Bridged; 4 Ω operation is not recommended |
1000W x 1, 8 Ω Bridged; 4 Ω operation is not recommended |
Standby: 1W Idle (no music playing): 160W Typical Listening levels: 300W Maximum: 1400W |
Standby: 1W Idle (no music playing): 160W Typical Listening levels: 300W Maximum: 1400W |
60 amps peak, per channel |
60 amps peak, per channel |
0.1% THD |
0.1% THD |
Yes |
Yes |
5 Hz - 100 kHz, +0/-3 dB 20 Hz - 20 kHz, +0/-0.25 dB |
5 Hz - 100 kHz, +0/-3 dB 20 Hz - 20 kHz, +0/-0.25 dB |
> 80 dB at 1 kHz > 70 dB at 20 kHz |
> 80 dB at 1 kHz > 70 dB at 20 kHz |
Unbalanced: 33 kΩ Balanced: 66 kΩ,(33 kΩ per leg) |
Unbalanced: 33 kΩ Balanced: 66 kΩ,(33 kΩ per leg) |
29 dB |
29 dB |
for 28.28 V Output into 8 Ω Unbalanced: 1 V Balanced: 1 V per leg |
for 28.28 V Output into 8 Ω Unbalanced: 1 V Balanced: 1 V per leg |
> 115 dB, input shorted, IHF A-weighted > 110 dB, input shorted, unweighted |
> 115 dB, input shorted, IHF A-weighted > 110 dB, input shorted, unweighted |
Audio Trigger: 2 mV - 10 mV |
Audio Trigger: 2 mV - 10 mV |
+9 Vdc to +12 Vdc, 5 mA |
+9 Vdc to +12 Vdc, 5 mA |
XLR Pin Identification 1 = Ground (Shield) 2 = Positive 3 = Negative (Return) |
XLR Pin Identification 1 = Ground (Shield) 2 = Positive 3 = Negative (Return) |
17.63" x 7.1" x 20" (448 x 181 x 508mm) (without feet) 17.63" x 7.75" x 20" (448 x 197 x 508mm) (with feet) Depth with cables: 21.5" (546 mm) |
17.63" x 7.1" x 20" (448 x 181 x 508mm) (without feet) 17.63" x 7.75" x 20" (448 x 197 x 508mm) (with feet) Depth with cables: 21.5" (546 mm) |
Net Weight: 88 lbs (39.9 kg)
Shipping Weight: 107 lbs (48.5 kg) |
Net Weight: 88 lbs (39.9 kg)
Shipping Weight: 107 lbs (48.5 kg) |
Channels |
Watts Per Channel |
Power Output @ 8 ohm |
Power Output @ 4 ohm |
Power Output Bridged @ 8 ohm |
Power Consumption |
Current Rating |
Total Harmonic Distortion (THD) |
Power RMS |
Frequency Response |
Audio Crosstalk |
Impedance Input |
Audio Gain |
Sensitivity Input |
Signal to Noise Ratio |
Amplifier Requirements |
External Trigger Voltage |
Connectors |
Dimensions (W x H x D) |
Weight |
We want to make our Affiliate program as easy as possible. That’s why we process all claims directly, without any third party telephone tag. Specific warranty terms and details from the manufacturer are below. View the full Parasound Warranty.
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