AudioQuest PowerQuest 303 Power Conditioner

Surge Protection That Doesn't Sacrifice Itself to Save You

The AudioQuest PowerQuest 303 protects your system from bad power. It doesn't wear out doing it.

Its non-sacrificial design can take repeated surges and spikes up to 6000V and 3000A. It keeps working afterward. Older surge protectors often fail quietly after one big hit. This one doesn't.

An Extreme Voltage Shutdown circuit also watches the line. If voltage climbs to 140VAC, the main relay opens fast, in under a quarter second. That cuts your gear off before real damage happens.

Twelve outlets split the load. Four High-Current outlets are for amplifiers. Eight Linear-Filtered outlets are sized for sources like a streamer, DAC, or preamp. This split keeps a hungry power amp from fighting your source gear for clean current.

Filtering Aimed at Noise, Not Current

AudioQuest's Linear Noise-Dissipation cuts more than −22dB of noise. It works in differential mode from 30kHz up to 1GHz. That's a wide enough range to catch the RF noise that switching power supplies and Wi-Fi routers dump onto your home's power.

Inside, copper conductors carry the current. They're the same semi-solid, direction-controlled Long-Grain Copper AudioQuest uses in its cables.

A 2-meter PQ-415 power cable ships in the box. It uses the same noise-dissipating copper conductors, rated for 15 amps at 120V.

The plug sits at a 45-degree, flat-to-wall angle. That lets the 303 tuck close behind a rack, even in a tight space. Rack ears are included too, if you'd rather mount it in a 2U slot than set it on a shelf.

What Reviewers Are Saying

Maxwell Geiger reviewed the PowerQuest 303 for Audiophilia on November 4, 2023. He wrote that "the baseline noise from my speakers was dramatically reduced once I introduced the PowerQuest 303 into the system."

He said it "had a positive effect on a basic power issue without negatively impacting the sound" of his system. His overall take: it's "practically designed, accessibly priced and widely available."

Who Is This Power Conditioner Best For?

• Anyone who has lost gear to a power surge before. The non-sacrificial design keeps protecting your system surge after surge, not just once.
• Systems mixing amplifiers and sensitive source gear. Separate outlet types keep the two from fighting over clean current.
• Listeners in older homes or noisy electrical areas. Wide-band filtering targets RF interference you may not even know you're fighting.
• Anyone building or upgrading a rack system. Included rack ears and a flat plug make it easy to mount or set on a shelf.
• Not the right fit for a high-current subwoofer or commercial-scale power amp. The 303 is sized for a normal home system.

How Does It Connect to Your System?

The included PQ-415 cable runs from the 303 to your wall outlet. It's rated for 15 amps at 120V. Plug your amplifier or integrated amp into one of the four High-Current outlets.

Route sources like a DAC, streamer, or preamp into the eight Linear-Filtered outlets. The 45-degree plug and 2U rack ears mean it fits well almost anywhere: behind a rack, tucked in a cabinet, or mounted into a rack frame.

Pairs Well With

Building your system? Here are some great companions for the AudioQuest PowerQuest 303:

• Power cables if you want to upgrade beyond the included PQ-415
• Integrated amplifiers to plug into one of the four High-Current outlets
• Interconnect cables to finish out a quieter, cleaner-running system
• Audio racks sized for 2U rack-mounting the 303 directly

Frequently Asked Questions

What does "non-sacrificial" surge protection mean?

Older surge protectors use parts that degrade or fail after one big surge, often silently. The 303 keeps protecting your system through many surges, up to 6000V and 3000A, instead of wearing out.

Why are there two different types of outlets?

The four High-Current outlets are built for amplifiers. They draw current in big bursts. The eight Linear-Filtered outlets suit steadier source components. That way, the two don't compete for clean power.

Can it be rack-mounted?

Yes. It ships with 2U rack ears already included, so it drops into a standard rack without buying extra hardware.

Does the included power cable matter, or should I upgrade it right away?

The included PQ-415 already uses Long-Grain Copper conductors and RF-noise dissipation. It's a real cable, not an afterthought.

A higher-tier AudioQuest power cable is a fine future upgrade. It's not a requirement.

What's the warranty?

AudioQuest covers the PowerQuest 303 for five years against defects in materials and workmanship.

Will it work with a subwoofer or a big power amp?

It works fine with typical home gear. But it isn't built for commercial-scale current draw. Very high-power amps and subwoofers may be better off plugged straight into the wall.

See It in Action

The Absolute Sound walks through the 303's design and protection features:

Shane Lee digs into how dirty household power actually is, and what the 303 does about it:

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Learn More

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