Halo A21+

The Parasound Halo A21+ delivers commanding power with effortless musicality. At 300 W per channel into 8 Ω (500 W into 4 Ω), and up to 1,000 W bridged, it drives any loudspeaker with authority while keeping the sound spacious, controlled, and fatigue-free. Based on legendary John Curl’s circuit design, the A21+ refines Parasound’s most celebrated power amp for today’s systems—blending raw performance with elegant simplicity. Balanced XLR and RCA inputs, 2 Ω stability, and flexible bridging make it an ideal match for both stereo and home theater setups.

Praised by audiophiles and reviewers alike: “The soundstage just bloomed. Bass is crisp… mids and highs are singing.” “Ridiculously high damping… bass is tight and controlled at all volumes.” “Delightful and satisfying from the first note… impossible to fault.” Winner of multiple awards and recommendations, including: Secrets of Home Theater & High Fidelity – Best Stereo Power Amplifier (2024) Stereophile – Recommended Component Future Audiophile – "Best Affordable Audiophile Power Amp"

Features & Specifications

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