Duelund 1uf Black Series Copper / Silver Foil (Cu/Ag) VSF Speaker Capacitor

Duelund VSF Black Series Copper/Silver Hybrid Capacitor (Loudspeaker)The VSF Black Cu-Ag pairs the tonal density and natural musicality of pure copper foil with the air, detail, and harmonic refinement that only silver can deliver. Built around Duelund's signature Virtual Stack Foil construction with the Black Series reinforced damping treatment, this hybrid design has become a favourite for high-end crossover work where listeners want the warmth and weight of copper without surrendering the resolution of silver.ConstructionUnlike a conventional bypass arrangement using two separate capacitors, the VSF Black Cu-Ag is a true integrated hybrid. A pure copper foil VSF capacitor is paired with a small pure silver foil bypass element, both housed within the same wax-impregnated paper-and-foil structure and finished with the Black Series outer damping treatment. The leadouts from the copper and silver sections are intertwined at the terminations, ensuring the silver bypass works in intimate parallel with the main copper capacitor without the parasitics introduced by external bypass wiring.The result preserves the VSF's defining strengths — flat, low-inductance geometry; mechanical rigidity; the absence of internal microphony — while extending performance into a region of openness and detail retrieval that pure copper alone cannot reach.Lead-outs are 1mm tinned copper. As with all VSF capacitors, the outer lead is connected to the outer foil and should be oriented toward the lowest-impedance path to ground in your crossover.Sonic CharacterThe Cu-Ag occupies a distinctive sonic position in the Duelund range. It retains the fundamental tonal richness, body, and easy musicality that made the pure copper VSF a benchmark, but adds a layer of top-end transparency, harmonic shimmer, and spatial precision contributed by the silver bypass. Vocals carry more presence and breath; cymbals, strings, and decay tails are reproduced with greater texture and air. Listeners often describe the result as combining the best of both materials — copper's grounding warmth with silver's clarity and dimensionality.A burn-in period of 50–100 hours is recommended.ApplicationsBest suited to series and parallel positions in tweeter and midrange networks where the upper octaves are most exposed. The Cu-Ag is also an excellent choice for full-range and single-driver loudspeaker designs where one capacitor carries the entire signal — situations where every gain in resolution and tonal accuracy is directly audible.Specifications Construction: Virtual Stack Foil (VSF), Black Series damped, copper/silver hybrid Conductors: Pure copper foil (main) with pure silver foil bypass, intertwined leadouts Dielectric: High-density paper, wax-impregnated Voltage rating: 100 VAC / 200 VDC Tolerance: ±2% Lead-outs: 1.0 mm tinned copper Standard values: 0.1 µF – 10 µF (other values to order) Country of origin: Denmark