The Performance Audio 40i sits in the middle of QED’s Performance interconnect range, above the entry-level Performance Audio 10 and below the step-up Performance Graphite. It replaces the original Performance Audio 40, which earned a five-star review from What Hi-Fi?, with a complete redesign centred on QED’s Solid Complementary Conductor technology.
Solid Complementary Conductor Technology
Where conventional interconnects use a single conductor type, the Audio 40i pairs two solid-core conductors of different diameters and metallurgy: a 0.643 mm 99.999% oxygen-free copper (OFC) conductor alongside a 0.404 mm silver-plated OFC (SPOFC) conductor, giving a combined cross-section of 0.45 mm². Each conductor is electrically isolated within the cable, and QED argues that this complementary arrangement provides a more complete signal path than a single conductor of equivalent gauge.
Low Capacitance Design
The cable uses a foamed polyethylene dielectric, chosen for its low dielectric constant compared with solid insulation materials. This, combined with the optimised conductor geometry, achieves a measured capacitance of 57 pF/m — low enough to preserve high-frequency detail and dynamics across the audio band. Self-inductance is 0.45 μH/m and loop resistance is 0.050 Ω/m.
Ferrite Jacket
Beneath the outer PVC jacket, a ferrite layer surrounds the braided foil shield. QED states that this ferrite jacket delivers measurable improvements to both high-frequency noise rejection and the amount of relevant signal information retained, enhancing timing accuracy and dynamics.
Precision RCA Connectors
The Audio 40i is terminated with six-leaf, 24k gold-plated RCA plugs. The multi-leaf contact design spreads the connection over a larger surface area for lower contact resistance, while the robust metal bodies feature tactile grips for secure insertion and removal.
What the Press Says
- “An exceptional budget interconnect with bags of detail.” — What Hi-Fi? ★★★★★ (February 2016, Performance Audio 40 predecessor)
| Conductor Type | Solid Complementary |
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| Metallurgy | 99.999% OFC & SPOFC |
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| Conductor Size | 1 × 0.643 mm & 1 × 0.404 mm |
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| Combined Cross-Section | 0.45 mm² |
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| Dielectric | Foamed Polyethylene |
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| Capacitance | 57 pF/m |
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| Self-Inductance | 0.45 μH/m |
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| Loop Resistance | 0.050 Ω/m |
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| Dissipation Factor @ 10 kHz | 0.00250 |
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| Outer Jacket | Black Pearl PVC |
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| Outside Diameter | 8.0 mm |
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| Also Available As | 0.6m, 1m, 2m, 3m |
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