AudioQuest PowerQuest 505 Power Conditioner

A Step Up in Filtering, Not Just a Bigger Box

The AudioQuest PowerQuest 505 sits above the entry-level 303 in AudioQuest's power lineup. The difference is mostly inside.

It carries the same non-sacrificial surge protection as the 303. That's rated for repeated 6000V and 3000A surges without wearing out. It also has the same Extreme Voltage Shutdown. That opens the main relay in under a quarter second if voltage climbs to 140VAC.

What changes is the filtering. Ultra-Linear Noise-Dissipation replaces the 303's standard Linear filtering. It adds common-mode filtering from 30kHz to 100MHz, on top of differential-mode filtering out to 1GHz.

Twelve outlets split the load the same way as the 303. Four High-Current outlets handle amplifiers and powered speakers. Eight Ultra-Linear Filtered outlets serve steadier sources, like a streamer, DAC, or TV.

A Power Cable Built to Match the Upgrade

The included 2-meter PQ-715 cable moves beyond the 303's PQ-415. It adds AudioQuest's ZERO-Tech and RF/ND-Tech. ZERO-Tech removes the electrostatic field between the cable's high and low conductors. That allows linear RF noise-dissipation without softening transients.

RF/ND-Tech adds a common-mode phase-cancelling array. It targets the RF noise a ground wire can otherwise pick up, like an antenna.

Semi-solid Long-Grain Copper conductors carry the current. They're rated for 15 amps at 120V. The same 45-degree, flat-to-wall plug and 2U rack ears carry over from the 303. The 505 fits just as easily behind a tight rack or mounted directly into one.

What Reviewers Are Saying

Jaap Veenstra reviewed the PowerQuest 505 alongside its siblings for Alpha Audio on March 9, 2024. Moving up from the 303, he wrote that "the picture is much calmer and smoother."

He called the jump "significant," adding that it comes "with a relatively small additional investment." His overall verdict on the 505: a "nice balance, much better than 303."

Who Is This Power Conditioner Best For?

• Anyone who found the 303 tempting but wants more headroom. Ultra-Linear filtering adds common-mode noise reduction the 303 doesn't have.
• Systems with several noise-sensitive source components. Eight Ultra-Linear Filtered outlets give each one a quieter, steadier feed.
• Listeners who want a serious cable in the box. The included PQ-715 uses AudioQuest's ZERO-Tech and RF/ND-Tech, not just basic copper.
• Anyone building or upgrading a rack-mounted system. Included 2U rack ears and a flat plug make it easy to rack-mount or shelve.
• Not the right fit if the 303 already solves your noise issues. The 505's extra filtering and cable come at a real price step up.

How Does It Connect to Your System?

The included PQ-715 cable runs from the 505 to your wall outlet. It's rated for 15 amps at 120V. Plug amplifiers or powered speakers into the four High-Current outlets.

Route sources like a DAC, streamer, or preamp into the eight Ultra-Linear Filtered outlets. The 45-degree plug and 2U rack ears let it sit flush behind a rack, tuck into a cabinet, or mount straight into a rack frame.

Pairs Well With

Building your system? Here are some great companions for the AudioQuest PowerQuest 505:

• Power cables if you want to move beyond the included PQ-715
• 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 505 directly

Frequently Asked Questions

How is the 505 different from the 303?

Both share the same outlet layout and surge rating. The 505 upgrades to Ultra-Linear filtering with added common-mode noise reduction, plus a more advanced included power cable.

What do ZERO-Tech and RF/ND-Tech actually do?

ZERO-Tech removes the electrostatic field between the cable's conductors. That aids noise dissipation without softening transients. RF/ND-Tech adds a common-mode phase-cancelling array. It reduces the RF noise a ground wire can otherwise pick up.

Can it be rack-mounted?

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

Why are there two different outlet types?

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

What's the warranty?

AudioQuest covers the PowerQuest 505 for five years against defects in materials and workmanship.

See It in Action

TTVJAudio walks through what the 505 protects against and how it's built:

Gramophone compares the 505 against its 303 and 707 siblings:

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Learn More

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