Parasound Halo A 21+
Power amplifier · Halo series · Discontinued
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The Parasound Halo A 21+ is a 2-channel power amplifier rated 300 W per channel at 8 Ω and 500 W at 4 Ω, for speakers down to 2 Ω. It has no decoding or volume control of its own, so it needs a receiver or processor with pre-outs in front of it.
Only powers speakers. It needs a receiver or processor in front of it.
$5,000 each (MSRP, September 2026)
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Speakers the Halo A 21+ can drive
Each pairing is checked by our compatibility engine: the speaker's impedance against this amplifier's rated minimum, and height decoding for height speakers. Whether it plays loud enough depends on how far you sit, which the 3D editor works out for your room.
Rated to drive them (98)
- Micca M-8C
8 Ω · 90 dB
- Micca MB42X
8 Ω · 85 dB
- Polk Monitor XT90
8 Ω · 89 dB
- Klipsch CDT-3650-C II
8 Ω · 93 dB
- Klipsch CDT-5650-C II
8 Ω · 94 dB
- Pioneer SP-BS22-LR
6 Ω · 85 dB
- Pioneer SP-FS52
6 Ω · 87 dB
- Sony SS-CS5
6 Ω · 87 dB
- Sony SS-CS8
6 Ω · 86 dB
- SVS Prime Satellite
8 Ω · 85 dB
- Polk Monitor XT15
8 Ω · 86 dB
- Polk Monitor XT30
8 Ω · 89 dB
- Polk RC60i
8 Ω · 89 dB
- Yamaha NS-IC800
8 Ω · 90 dB
- Monoprice Alpha 8in Carbon Fiber 2-way
8 Ω · 90 dB
- Sony SS-CS3
6 Ω · 88 dB
- Polk Monitor XT60
8 Ω · 86 dB
- Polk Signature Elite ES10
8 Ω · 87 dB
- Polk RC80i
8 Ω · 90 dB
- SVS Prime Elevation
8 Ω · 87 dB
- Polk Monitor XT20
8 Ω · 87 dB
- Polk Monitor XT35
8 Ω · 87 dB
- Polk Signature Elite ES30
8 Ω · 89 dB
- Klipsch R-50C
8 Ω · 96 dB
- Paradigm Monitor SE 2000C
8 Ω · 93 dB
- Pioneer SP-BS22A-LR
6 Ω · 85 dB
- JBL Stage 240B
6 Ω · 85 dB
- JBL Stage 240H
6 Ω · 87 dB
- ELAC DC53
6 Ω · 87.5 dB
- Polk Monitor XT70
8 Ω · 89 dB
- SVS Prime Bookshelf
8 Ω · 87 dB
- Polk Signature Elite ES50
8 Ω · 89 dB
- ELAC A4.2
6 Ω · 85 dB
- ELAC DB53
6 Ω · 86.5 dB
- Polk Signature Elite ES20
8 Ω · 88 dB
- Wharfedale Diamond 12.C
8 Ω · 90 dB
- Paradigm Monitor SE Atom
8 Ω · 89 dB
- Klipsch R-50M
8 Ω · 92 dB
- JBL Stage 245C
6 Ω · 91 dB
- JBL Stage 250B
6 Ω · 86 dB
- Polk Signature Elite ES90
4 Ω · 85 dB
- SVS Prime Center
8 Ω · 86 dB
- ELAC B6.2
6 Ω · 87 dB
- Klipsch RP-500C II
8 Ω · 94 dB
- Wharfedale Diamond 12.1i
8 Ω · 88 dB
- JBL Stage 260F
6 Ω · 90 dB
- Klipsch R-600F
8 Ω · 96 dB
- Klipsch RP-500M II
8 Ω · 92 dB
- KEF Q250c
8 Ω · 87 dB
- Klipsch RP-5000F II
8 Ω · 95 dB
- Paradigm Monitor SE 6000F
8 Ω · 93 dB
- MartinLogan Motion AFX
4 Ω · 87 dB
- ELAC DF63
4 Ω · 87.5 dB
- Klipsch RP-500SA II
8 Ω
- JBL Stage 280F
6 Ω · 91 dB
- Klipsch R-40SA
8 Ω
- Focal Vestia Center
8 Ω · 91.5 dB
- Polk Reserve R100
8 Ω · 86 dB
- Polk Reserve R400
8 Ω · 89 dB
- Polk Reserve R500
8 Ω · 87 dB
- KEF Q1 Meta
4 Ω · 86 dB
- Klipsch RP-6000F II
8 Ω · 96 dB
- Klipsch RP-600M II
8 Ω · 94.5 dB
- SVS Prime Tower
8 Ω · 87 dB
- Klipsch RP-504C II
8 Ω · 96 dB
- MartinLogan Motion 35XTi
4 Ω · 92 dB
- Monitor Audio Bronze AMS 7G
8 Ω · 86 dB
- KEF Q350
8 Ω · 87 dB
- Klipsch R-605FA
8 Ω · 96 dB
- Klipsch RP-8000F II
8 Ω · 98 dB
- SVS Ultra Evolution Center
6 Ω · 87 dB
- Monitor Audio Bronze 50 7G
8 Ω · 86 dB
- KEF Q6 Meta
4 Ω · 86 dB
- Klipsch RP-502S II
8 Ω · 94 dB
- MartinLogan Motion XT B100
4 Ω · 93 dB
- SVS Ultra Evolution Elevation
6 Ω · 87 dB
- KEF Q3 Meta
4 Ω · 87 dB
- KEF Q750
8 Ω · 88 dB
- KEF Q8 Meta
4 Ω · 86 dB
- Bowers & Wilkins HTM6 S3
8 Ω · 87 dB
- KEF Q7 Meta
4 Ω · 87 dB
- SVS Prime Pinnacle
8 Ω · 88 dB
- Bowers & Wilkins 607 S3
8 Ω · 84 dB
- Sonus faber Lumina Center I
4 Ω · 87 dB
- SVS Ultra Evolution Bookshelf
6 Ω · 87 dB
- Bowers & Wilkins 606 S3
8 Ω · 88 dB
- Sonus faber Lumina I
4 Ω · 84 dB
- KEF Q11 Meta
4 Ω · 89 dB
- Focal Vestia N°1
8 Ω · 89.5 dB
- KEF Q Concerto Meta
4 Ω · 85 dB
- KEF LS50 Meta
8 Ω · 85 dB
- MartinLogan Motion XT C100
5 Ω · 93 dB
- Focal Vestia N°3
8 Ω · 92 dB
- MartinLogan Motion XT F100
4 Ω · 92 dB
- Bowers & Wilkins 603 S3
8 Ω · 90 dB
- Sonus faber Lumina III
4 Ω · 89 dB
- SVS Ultra Evolution Titan
6 Ω · 88 dB
- SVS Ultra Evolution Pinnacle
6 Ω · 88 dB
Halo A 21+ specifications
| Channels | 2 |
|---|---|
| Power | 300 W at 8 Ω |
| Lowest impedance | 2 Ω |
| Inputs | RCA, XLR |
| Size | 18×8×20 in |
| Power at 4 Ω | 500 W |
| Weight | 32.2 kg (71 lb) |
| MSRP | $5,000 each (MSRP, September 2026) |
Every value comes from the sources under References, last retrieved September 15, 2026.
Questions about the Halo A 21+
- How many watts per channel is the Halo A 21+?
- 300 W per channel into 8 Ω (500 W into 4 Ω), with 2 channels driven, across 2 channels.
- Can the Halo A 21+ drive 4 ohm speakers?
- Yes. It is rated for loads down to 2 Ω.
- Do I need a receiver with the Halo A 21+?
- Yes. A power amplifier has no decoding or volume control of its own; connect it to the pre-outs of an AV receiver or processor.
- What inputs does the Halo A 21+ have?
- Unbalanced RCA and balanced XLR.
- How big is the Halo A 21+?
- The Parasound Halo A 21+ measures 448 × 197 × 508 mm (17.6 × 7.8 × 20 in, width × height × depth) and weighs 32.2 kg (71 lb).
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References
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