Shunyata Research Sigma-X QR Power Cable | Reference Power Cord
Shunyata Research Sigma-X QR is the top model in the Sigma-X power cable family. It adds Shunyata's patented QR/BB module, a charge reservoir for instantaneous current, to the same Gen3 NR noise reduction used in Sigma-X NR. Shunyata recommends it particularly for high-powered amplifiers, and for source and digital components when you want the highest Sigma-X performance.
If your component doesn't need QR/BB, Sigma-X NR offers the same Gen3 NR platform for any component. For the wall connection to a Shunyata power distributor, choose Sigma-X XC. See all our Shunyata Research cables and power products.
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SIGMA-X QR POWER CABLE
Shunyata Research Sigma-X QR is the highest-performing power cable in the Sigma-X family. It combines patented QR/BB with Gen3 NR noise reduction, two TAPc polarizers, 6-gauge VTX-Ag conductors, CopperCONN connectors, fluorocarbon dielectric and four days of KPIP v2 processing.
WHO IS SIGMA-X QR FOR?
Shunyata designed Sigma-X QR particularly for high-powered amplifiers. It can also be used on source and digital components when only the highest Sigma-X performance will do.
SIGMA-X QR VS. NR
Both use Gen3 NR, rated at greater than 6 dB of noise reduction at 1 MHz, and two TAPc polarizers. QR adds Shunyata's patented QR/BB and NIC. If QR/BB isn't needed, Sigma-X NR is the reference noise-reducing choice for any component.
TECHNOLOGY
 | QR/BB is Shunyata Research's patented technology (US 10,031,536), previously found only in its Omega power cords. It acts as an electric charge reservoir, storing and releasing energy to improve a component's access to instantaneous current. |
 | TAPc (Transverse Axial Polarizer) is Shunyata Research's patent-pending technology, developed for its reference signal cables and made small enough to use in power cords. Sigma-X QR uses two TAPc polarizers. |
 | Gen3 NR is the third-generation noise-reduction circuit Shunyata uses in its Alpha-X and Sigma-X power cords. Sigma-X QR is specified for greater than 6 dB of noise reduction at 1 MHz. |
 | VTX-Ag conductors combine a pure-silver center conductor with a concentric pure-copper outer conductor. Sigma-X QR uses this geometry at 6 gauge. |
 | CopperCONN connectors use pure copper contacts, which have higher conductivity than the brass used in many audio connectors. Sigma-X QR uses CopperCONN AC and IEC connectors with carbon-fiber bodies. |
 | Fluorocarbon dielectric offers very low dielectric absorption, high dielectric strength and excellent heat resistance. |
 | KPIP v2™ is Shunyata Research's proprietary Kinetic Phase Inversion Process, applied to the conductor metals. Sigma-X QR receives four days of KPIP v2 processing, which Shunyata says greatly reduces burn-in time. |
SPECIFICATIONS
Conductors: VTX-Ag Gauge: 06 Construction: 1″ tube Dielectric: Fluorocarbon Noise Reduction: > 6 dB @ 1 MHz Tech: QR/BB, NIC, TAPc polarizer 2x | AC Connector: CopperCONN™ Carbon-Fiber IEC Connector: CopperCONN™ Carbon-Fiber (C15 or C19) KPIP v2 Processing: 4 days Color: Black flex Standard Length: 1.75 meters Safety Assurance: |
CHOICE AUDIO GUIDANCE
QR is the Sigma-X power cable we prioritize for demanding amplifiers and reference components when maximum Sigma-X performance is the goal.
FREQUENTLY ASKED QUESTIONS
Does QR include noise reduction?
Yes. Shunyata specifies greater than 6 dB at 1 MHz.
What separates QR from NR?
QR adds patented QR/BB technology and NIC.
Should I use QR between the wall and a Shunyata power distributor?
Shunyata designed Sigma-X XC for that connection, because its distributors already filter the power. With other brands' power conditioners, Shunyata says the NR-equipped models will likely help.
What is the standard length?
1.75 meters.