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HPA4

Uses the same patented THX AAA topology as the Benchmark AHB2 power amplifier and rates bandwidth from 0.01 Hz to above 500 kHz.

Type
Solid-state headphone amplifier
Output
6 W into 16 ohms
Weight
3.6 kg
List
$3,499

Output into any load

The line is what the HPA4 delivers, estimated from its published ratings. Each square is a headphone in the catalog at the power it needs for a loud 110 dB peak.

Grado Signature HP100 SE: needs 0.20 mW at 38 ohmsFocal Stellia: needs 2.51 mW at 35 ohmsAudeze MM-520: needs 6.31 mW at 18 ohmsFocal Clear MG: needs 3.98 mW at 55 ohmsFostex TH900mk2: needs 10.0 mW at 25 ohmsMeze Audio Elite: needs 7.94 mW at 32 ohmsFocal Utopia (2022): needs 3.98 mW at 80 ohmsRosson Audio Design RAD-0: needs 15.8 mW at 29 ohmsYamaha YH-5000SE: needs 15.8 mW at 34 ohmsSony MDR-Z1R: needs 10.0 mW at 64 ohmsHIFIMAN HE1000se: needs 25.1 mW at 35 ohmsFinal D8000 Pro Edition: needs 15.8 mW at 60 ohmsZMF Caldera: needs 31.6 mW at 60 ohmsDan Clark Audio Stealth: needs 100 mW at 23 ohmsDan Clark Audio Expanse: needs 100 mW at 26 ohmsMeze Audio Empyrean II: needs 100 mW at 32 ohmsAudeze LCD-5s: needs 100 mW at 35 ohmsMeze Audio ARTA: needs 15.8 mW at 225 ohmsZMF Vérité Closed: needs 12.6 mW at 300 ohmsAudio-Technica ATH-ADX5000: needs 10.0 mW at 420 ohmsSennheiser HD 820: needs 16.6 mW at 300 ohmsSennheiser HD 800 S: needs 20.9 mW at 300 ohmsAbyss Diana TC Signature: needs 100 mW at 72 ohmsAbyss AB-1266 Phi TC: needs 158 mW at 50 ohmsHIFIMAN Susvara: needs 501 mW at 60 ohmsPublished: 6 W into 16 ohms
Output into each loadPublished ratingHeadphone it drives at 110 dB (25)Needs more (0)Load in ohms across, power up, both on log scales

Build a setup with it

Start with the Abyss AB-1266 Phi TC, the hardest headphone here it drives with power in reserve.

Open in the setup builder →

Where to buy

$3,499

Price: without remote; $3,599 with remote; rackmount versions $3,699 and $3,799.

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Title block

Maker
Benchmark
Model
HPA4
Type
Solid-state headphone amplifier
Made in
USA
Output impedance
Not published
Maximum voltage
11.5 V RMS
Weight
3.6 kg
List price
$3,499 USD
Output power
6 W into 16 ohms
Topology
THX-888 (Achromatic Audio Amplifier) feed-forward error-correction amplifier; 100% analog signal path; 256-step relay gain control
Finish
Milled aluminium faceplate and sides, brushed aluminium top, bottom and rear; black or silver faceplate

What it drives

How the matching works

Plenty in reserve

10 dB or more above loud 110 dB peaks.

24

Enough

Reaches loud 110 dB peaks with up to 10 dB to spare.

1

Other solid-state amplifiers

Sources