iFi Audio SilentPower DC Blocker+ Reduce Transformer Hum

iFi SilentPower DC Blocker+

SilentPower’s DC Blocker+ is a high-performance DC offset filter that installs at your component’s IEC power inlet to stop unwanted DC voltage from riding on the AC mains. By blocking incoming DC (up to 1,200mV), it helps eliminate transformer mechanical hum, improves transformer efficiency, and can reduce heat—so your amplifier, DAC, or AV gear runs quieter and sounds cleaner. Built for demanding systems, it’s globally compatible (90–250V) and engineered for high-power equipment with a 10A continuous current rating and up to ≤14A maximum current rating. Hospital-grade IEC connectors, retained EMI shielding, and a compact chassis make it an easy, confidence-inspiring upgrade that won’t get in the way of other plugs and cables. If your toroidal transformer is buzzing, the DC Blocker+ is the simple “fit-and-forget” fix that restores quiet backgrounds and uninterrupted listening.

What It's Good At:

• Eliminating transformer mechanical hum caused by DC offset on the mains
• Improving system quietness for cleaner detail, tighter bass definition, and better clarity
• Supporting high-power amplifiers and AV gear with a 10A continuous current rating
• Maintaining EMI shielding for ongoing noise suppression without compromising safety
• Clean, compact IEC-in/IEC-out installation that won’t block nearby sockets or cables
• Delivering dependable, premium connectivity with hospital-grade IEC connectors

iFi SilentPower DC Blocker+ Full Specifications:

• Product name: DC Blocker+
• Brand/line: SilentPower by iFi
• SKU: 03-06-064-0001-01
• Type: DC induced noise reducer / DC offset blocker (mains DC filter)
• Input/Output: Universal IEC (IEC-in/IEC-out inline installation at device power inlet)
• ZERO DC Block Technology: Blocks incoming DC up to 1,200mV (also described as intelligently blocking over 1,000mV DC)
• Voltage rating (global compatibility): 90–250V
• Continuous current rating: 10A
• Maximum current rating: ≤14A
• Max amplifier power (guideline): 2200W or VA @ 220V / ~1100W or VA @ 110V
• Connectors: Hospital-grade IEC connectors
• EMI shielding: Retained for continued noise suppression
• Safety: Equipment safety is unaffected (designed not to compromise safety)
• Dielectric strength: 1500VRMS (high-case dielectric strength)
• Compliance/material notes: UL listed; flame resistant IEC socket/connector/chassis (fireproof polymers UL94-V0)
• Dimensions: 75 × 46 × 32 mm (3.0" × 1.8" × 1.3")
• Net weight: 80 g (2.8 oz)
• Limited warranty: 12 months
• In the box: 1× DC Blocker+; 1× User Manual
• Design note: Compact form factor designed not to obstruct other connectors, sockets, or cables

iFi SilentPower DC Blocker+ Q&A:

Will the DC Blocker+ stop transformer hum in my amplifier?

Yes—DC Blocker+ is designed to block unwanted DC voltage on the AC mains (up to 1,200mV), a common cause of toroidal transformer mechanical hum.

Where do I install the DC Blocker+?

Install it inline at the component’s power inlet: plug the DC Blocker+ male IEC into your device, then connect your existing IEC power cable into the DC Blocker+ female IEC.

Is it safe to use with expensive audio equipment?

It is designed to preserve equipment safety while addressing DC offset, and it retains EMI shielding for continued noise suppression.

Will it work in my country’s voltage?

Yes. It’s globally compatible and rated for 90–250V operation.

Can I use it with high-power amplifiers and AV receivers?

Yes. It’s built for high-power equipment with a 10A continuous current rating (≤14A maximum) and supports high amplifier power demands.

Does it improve sound quality or only reduce hum?

By removing DC-induced transformer noise and helping reduce interference, it can lower noise floors and improve perceived clarity, focus, and overall listening comfort.

Will it block other plugs or cables behind my gear?

Unlikely—the compact design is intended not to obstruct nearby connectors and cables.

What comes included with the DC Blocker+?

You receive the DC Blocker+ and a user manual for quick, straightforward setup.