Benchmark AHB2 Silver Rackmount left front
Benchmark AHB2 Silver - top front
Benchmark AHB2 Black - right front low angle
Benchmark AHB2 Silver - right front closeup
Benchmark AHB2 Black top front
Benchmark AHB2 Black right front closeup
Benchmark AHB2 Silver Rackmount top front
Benchmark AHB2 Black Rackmount top front
Benchmark AHB2 Rear
Benchmark AHB2 rear panel
Benchmark AHB2 dimensions
Benchmark AHB2 Rackmount dimensions
AHB2 Output Waveform at 1 Watt
Benchmark AHB2 Silver Rackmount left front
Benchmark AHB2 Silver - top front
Benchmark AHB2 Black - right front low angle
Benchmark AHB2 Silver - right front closeup
Benchmark AHB2 Black top front
Benchmark AHB2 Black right front closeup
Benchmark AHB2 Silver Rackmount top front
Benchmark AHB2 Black Rackmount top front
Benchmark AHB2 Rear
Benchmark AHB2 rear panel
Benchmark AHB2 dimensions
Benchmark AHB2 Rackmount dimensions
AHB2 Output Waveform at 1 Watt
Benchmark AHB2 Silver Rackmount left front
Benchmark AHB2 Silver - top front
Benchmark AHB2 Black - right front low angle
Benchmark AHB2 Silver - right front closeup
Benchmark AHB2 Black top front
Benchmark AHB2 Black right front closeup
Benchmark AHB2 Silver Rackmount top front
Benchmark AHB2 Black Rackmount top front
Benchmark AHB2 Rear
Benchmark AHB2 rear panel
Benchmark AHB2 dimensions
Benchmark AHB2 Rackmount dimensions
AHB2 Output Waveform at 1 Watt

Benchmark AHB2 Power Amplifier

Regular price
$ 3,599.00 USD
Sale price
$ 3,599.00 USD
Regular price
$ 3,599.00 USD
Shipping calculated at checkout.
Unique Patented Technology
Quietest, Cleanest Amplifier on the Planet!
Top Awards
Proven Bulletproof Reliability
Drives Difficult Loads with Ease
Style: Silver
Faceplate:
9 In Stock

SKU: 500-18000-300

Recommendations

Stereophile

"Benchmark Media Systems' AHB2 is an extraordinary amplifier. Not only does its performance lie at the limits of what is possible for me to reliably test, it packs high power into a very small package, especially when used in bridged-mono mode. It is truly a high-resolution amplifier."

- John Atkinson, Stereophile
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Stereophile 2025 Recommended Components  Logo
Future Audiophile

"Less distortion and noise than any other power amp I’ve measured over the years"

- Bascom King, BHK Labs, SoundStage!
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Sound Stage Hifi .com Recommended Reference Award
Stereo Times

"The Benchmark performance continues to engage me, and the company gives me confidence in long-term support. I never get tired of listening with the Benchmarks. Found a Home in My System."

- Don Shaulis, Stereo Times
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The Stereo Times Publishers Choice 2022 Award

The Benchmark AHB2

The AHB2 is a radically different audio amplifier. Its patented design delivers performance that approaches the limits of the latest high-resolution audio formats. Benchmark's AHB2 power amplifier delivers musical details without introducing the masking effects of amplifier noise and distortion. The dynamic range of the AHB2 is 132 dB, making it 10 to 30 dB quieter than some of the very best reference-quality power amplifiers.

Unlike class-D amplifiers, the AHB2 is noise free over its ultra-wide 0.1 Hz to 200 kHz frequency range. Don't settle for the limited performance of class-D amplification.

With the AHB2, you will discover previously overlooked nuances, dynamics, and detail in your favorite tracks. Experience the full potential of the very best high-resolution 24-bit PCM and 1-bit DSD recordings.

Technology of the AHB2

Feed-Forward Error Correction

  • Much Faster than Feedback
  • Eliminates Zero-Crossing Distortion
  • Inherently Stable, Non-Recursive Correction
  • Stable into Any Phase Angle
  • Stable when Driving Very Low impedances
  • No Rise in THD when Driving Low Impedances
  • No Rise in THD when Running in Bridged Mono
Learn More

Patented THX-AAA Technology

  • Benchmark Exclusive
  • Not Available on Any Other Power Amplifier
  • 30 to 40 dB reduction in THD
  • Keeps THD+N Below 0 dB SPL at All Times
  • No "Electronic Fingerprints" on the Music
  • Accurate Impulse Response Into all Loads
  • 132 dB SNR
Learn More

Extended Frequency Response

  • Ultra Wide 0.1 Hz to 200 kHz Response
  • Bass is Delivered Without a Phase Shift
  • Fast, Distortion-Free Transient Response
  • Linear Phase Response
  • Accurately Reproduces the Audio Waveshape
  • Precise Rendering of Stereo Width and Depth
  • Focused 3-D Stereo Image
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Unique Features

  • Class-AB with Class-H Tracking Rails - High Power, Runs Cool
  • No Class-D Amplification - No Ultrasonic Noise
  • Tightly Regulated Power Supply with AC Line Conditioning
  • Immune to AC Line Noise
  • Power Does not Change with Line Voltage
  • THD+N Does Not Change with Line Voltage
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Bulletproof Protection Circuits

  • Complete Monitoring of Current, Voltage, THD, and Temperature
  • No Performance-Compromising Protection Circuits in the Signal Path
  • Lightning-Fast Tweeter Protection if THD Exceeds 2%
  • Noise-Free Electronic Mute Under Fault Conditions
  • Fault And Clip Indicator Lights
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Bridged-Mono Switch

  • 100 W Stereo – Generous Power for Most Applications
  • 380 W Mono – Suitable for Large Rooms or Extreme SPL Levels
  • Nearly a 4X Power Increase in Bridged Mono
  • No increase in THD when Running in Bridged Mono
  • Flexible Upgrade Path – Start with Stereo, Upgrade to Bridged Mono
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Best of the Best

The Benchmark AHB2 delivers the lowest noise and lowest distortion available at any price.
This performance is achieved using a unique, patented technology that sets it apart from competition. In many ways, the Benchmark AHB2 is radically different than traditional amplifiers. It has earned many top industry awards in recognition of its performance and innovation. It can be found on Stereophile's top list of "recommended components".

The AHB2 is known for its natural sound, and it has earned a reputation for proven, bulletproof reliability. Additionally, the Benchmark AHB2 can effortlessly drive the most difficult speaker loads without exhibiting an increase in THD.
Benchmark AHB2 with a silver front panel on a rustic wooden box

Listening Experience


The Benchmark AHB2 delivers a clear, open, and uncluttered playback across the entire frequency range.

Instrumental overtones are rendered with exceptional precision and realism. Vocals are reproduced with outstanding accuracy and natural tones. Transients are fast and precise. Bass is deep and well controlled.

The ultra-linear phase response of the AHB2, allows it to create a precise three-dimensional rendering of the recorded space. This space is open and uncluttered because noise and distortion are held below the 0-dB SPL threshold of hearing at all playback levels.
From the first watt to the last watt, the AHB2 delivers a clear image of the musical performance. Pure excitement, no distractions.
Benchmark AHB2 on a rustic wooden box

Awards

Front Panel

Benchmark AHB2 Front Panel View
POWER
  • On/Off Momentary Switch
  • Indicator Off - Power is Off
  • Indicator On - Power is On
  • Indicator Flashing - Fault Condition, Protection Enabled, Power Disabled
CLIP Indicators
  • Off - Normal
  • Flash - Clip
  • On - Speaker Protection Enabled Due to Excessive Clipping
TEMP Indicators
  • Off - Normal
  • Flash - Peak-Current Warning
  • TEMP On and POWER On - Over-Current Protection Enabled
  • TEMP On and POWER Flashing - Over-Temperature Protection Enabled
MUTE Indicators
  • Off - Normal
  • On - Audio is Muted

Rear Panel

Benchmark AHB2 Rear Panel
Two Balanced XLR Inputs
  • Support Studio or HiFi Input Levels
  • High CMRR for Noise Immunity
  • Support Benchmark RCA to XLR Adapters
3-Position SENSITIVITY Switch
  • Up - 2V RCA Source (with Adapter)
  • Center - 4V HiFi XLR Source
  • Down - +22 dBu Studio XLR Source
Three SpeakON Outputs
  • High-Current NL2/NL4 Twist-Lock Connectors
  • Better Electrical Connection than Binding Posts
  • Quick and Easy Operation
  • No Risk of Shorts or Polarity Reversals
  • Dedicated Bridged-Mono Output Connector
MODE Switch
  • Up - Bridged Mono
  • Down - Stereo
  • Unit Mutes when Switching Modes
Two 12V TRIGGER I/O Ports
  • Bidirectional Operation
  • Work with all Single and Dual Direction Trigger Ports
  • Time Delays Allow Noise-Free System Startup and Shutdown
AC Input
  • Standard 3-Pin IEC Connector
  • Fuse Drawer with Two Fuses
  • Auto-Ranging
  • 50-60 Hz
Binding Posts
  • Insulated to Comply with Safety Regulations
  • Accept Bare Wire, Spades, or Banana Plugs
  • Use SpeakON Outputs for Highest Performance
TUV Safety Certification
  • International Certifications
  • Safety Tested
  • Production Monitored

Additional Information

Manual

Detailed specifications and performance plots are available in the downloadable manual.

AHB2 Manual

AHB2 Application Notes

AHB2 App Notes

Reviews

AHB2 Reviews

Continuous Average Output Power

< 0.0003 % THD+N at full rated power, 20 Hz to 20 kHz

  • 100 Watts per channel into 8 Ohms, both channels driven
  • 130 Watts per channel into 6 Ohms, both channels driven
  • 190 Watts per channel into 4 Ohms, both channels driven
  • 240 Watts per channel into 3 Ohms, both channels driven
  • 259 Watts per channel into 2 Ohms, both channels driven
  • 200 Watts into 16 Ohms, bridged mono
  • 380 Watts into 8 Ohms, bridged mono
  • 480 Watts into 6 Ohms, bridged mono
  • 518 Watts into 4 Ohms, bridged mono

All speakers have variations in input impedance. Select loads based on nominal impedances not minimum impedances. The AHB2 is stable into all loads. The AHB2 is conservatively rated at an output level where THD+N is < 0.0003 % instead of the more typical 1% THD+N. Power at 1% THD will be higher.

Output Voltage Into Various Load Impedances

< 0.0003% THD+N at the following output voltages and load impedances, 20 Hz to 20 kHz

  • 29.03 dBV, 31.25 dBu, 28.28 Vrms into 8 Ohms, both channels driven
  • 28.92 dBV, 31.14 dBu, 27.93 Vrms into 6 Ohms, both channels driven
  • 28.81 dBV, 31.03 dBu, 27.57 Vrms into 4 Ohms, both channels driven
  • 28.57 dBV, 30.79 dBu, 26.83 Vrms into 3 Ohms, both channels driven
  • 27.14 dBV, 29.36 dBu, 22.76 Vrms into 2 Ohms, both channels driven
  • 35.05 dBV, 37.27 dBu, 56.57 Vrms into 16 Ohms, bridged mono
  • 34.83 dBV, 37.05 dBu, 55.14 Vrms into 8 Ohms, bridged mono
  • 34.59 dBV, 36.81 dBu, 53.67 Vrms into 6 Ohms, bridged mono
  • 33.16 dBV, 35.38 dBu, 45.52 Vrms into 4 Ohms, bridged mono

Use dBV to calculate the peak SPL from your speaker/amplifier combination. Use the following formula: Amplifier output voltage in dBV + speaker sensitivity at 2.83V - 9 dB. Example: (29.03 dBV at 8 Ohms) + (90 dB SPL @ 2.83V 1m) - 9 dB = 110 dB SPL at 1 meter

SNR & Dynamic Range

Rated output relative to output noise, inputs shorted

  • 132 dB A-weighted, Stereo Mode
  • 135 dB A-weighted, Mono Mode
  • 130 dB Unweighted, 20 Hz to 20 kHz, Stereo Mode
  • 133 dB Unweighted, 20 Hz to 20 kHz, Mono Mode

Noise Voltage

Output noise voltage, A-weighted, inputs shorted

  • -103 dBV, -101 dBu, 7.1 uVrms, Stereo Mode
  • -100 dBV, -98 dBu, 9.8 uVrms, Mono Mode

Use dBV to calculate the SPL of the noise produced by your speaker/amplifier combination. Use the following formula: Amplifier output noise voltage in dBV + speaker sensitivity at 2.83V - 9 dB. Example: Mono mode driving very high efficiency speakers: (-100 dBV) + (104 dB SPL @ 2.83V 1m) - 9 dB = -5 dB SPL at 1 meter. This means that the system noise will be 5 dB below the threshold of hearing when driving speakers with a very high 104 dB efficiency. The noise will be even further below the threshold of hearing when driving typical speakers.

Noise Relative to 2.83 Vrms (1 Watt into 8 Ohms)

Output noise relative to 2.83 Vrms, A-weighted, inputs shorted

  • -112 dB, Stereo Mode
  • -109 dB, Mono Mode

THD+N

1 kHz, 80 kHz LPF, at full rated output into any rated load

  • < -118 dB (< 0.00013%), Stereo Mode
  • < -118 dB (< 0.00013%), Mono Mode

THD

1 kHz, 20 kHz LPF, at full rated output into any rated load

  • < -119 dB (< 0.00011%), Stereo Mode
  • < -120 dB (< 0.00010%), Mono Mode

Crosstalk

  • Better than -115 dB at 1 kHz
  • Better than -92 dB at 20 kHz

Frequency Response

  • Better than 0.1 Hz to 200 kHz, +0/-3 dB
  • -0.01 dB at 20 Hz, -0.17 dB at 20 kHz, 8-Ohm Load
  • -0.23 dB at 20 Hz, -0.32 dB at 20 kHz, 4-Ohm Load

Damping Factor

  • 350 at 20 Hz, 8-Ohms
  • 254 at 1 kHz, 8-Ohms
  • 34 at 20 kHz, 8-Ohms
  • 7 at 200 kHz, 8-Ohms

Maximum Audio Output Current

  • 29 A peak, per channel, both channels driven

Input Sensitivity

  • Low-Gain = 22 dBu (9.8 Vrms), Gain = 9.2 dB
  • Mid-Gain = 14.2 dBu (4 Vrms), Gain = 17.0 dB
  • High-Gain = 8.2 dBu (2 Vrms), Gain = 23 dB
  • Use Mid-Gain or High-Gain settings for unbalanced inputs
  • Unbalanced inputs require RCA to XLRM adapter cables

Input Impedance

  • 50 k Ohms, normal mode
  • 1 M Ohm, common mode

Input CMRR

  • 80 dB at 20 Hz, typical
  • 80 dB at 1 kHz, typical
  • 65 dB at 20 kHz, typical

Trigger I/O

  • 12 VDC 200 mA current-limited output to trigger turn-on of remote devices
  • DC input for slaving to remote devices
  • Input responds to 3.3 V logic and higher, VIL = 1.26 V, VIH = 2.7 V
  • Absolute maximum input voltage = 30 VDC
  • Absolute minimum input voltage = -0.3 VDC
  • Input Impedance = 20 k Ohms

Protection Circuits

  • Fully Electronic, No Relays
  • Mute Sequencing
  • Distortion Detection
  • Short Circuit Detection
  • Over Current Detection
  • Over Temperature Detection
  • SOA Detection (Output device safe operating area)

Dimensions

Non-rack-mount version:
  • 11.04" W x 3.88" H x 9.34 " D - Including feet and binding posts
  • 11.04" W x 3.47" H x 8.33 " D - Excluding feet and connectors
  • Faceplate height is 2RU
Rack-mount version:
  • 19.00" W x 3.88" H x 10.62 " D - Including binding posts, handles and removable feet
  • 19.00" W x 3.47" H x 8.33 " D - Excluding feet and connectors
  • 9.09" rack depth, including binding posts, excluding cables
  • 11" rack depth, including cables
  • Faceplate height is 2RU

Weight

  • 12.5 lbs., 16 lbs. shipping - Non-rack-mount version
  • 13.5 lbs., 17 lbs. shipping - Rack-mount version

AC Input

  • Auto-ranging AC Input
  • 100 to 120 VAC +/- 10%, 8 Amps, 50 - 60 Hz
  • 220 to 240 VAC +/- 10%, 8 Amps, 50 - 60 Hz
  • Idle Power Consumption = 20 W
  • Standby Power Consumption < 0.5 W

The Benchmark Product Line

Benchmark ... the measure of excellence! ®
  • Benchmark AHB2 on a rustic wooden box

    Power Amplifiers

    The AHB2 sets the benchmark for the lowest noise and lowest distortion in a power amplifier ... at any price.

    Power Amplifiers
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    Hi-Fi Preamplifiers

    Benchmark preamplifiers are designed to accept and deliver studio-level balanced output signals, but they also deliver state-of-the-art performance when operating at HiFi signal levels which are typically 10 dB lower.

    Hi-Fi Preamplifiers
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    Digital to Analog Converters

    High-Resolution Playback Begins with an External D/A Converter

    Digital to Analog Converters
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    Cables

    Benchmark Studio&Stage™ professional audio cables deliver the high performance required for studio applications while delivering the durability to withstand the most demanding live sound applications.

    Cables
5.00 from 350+ reviews

Designed for Accuracy, Built for Transparency

We are passionate about audio quality.
Benchmark LA4, DAC3 B, and AHB2 on a rustic wooden rack.