Mercury 100V Line Speaker Cable 1.15mm² Black - 25m Reel

The Mercury 100V line speaker cable is a 2-core cable with a 1.15mm² cross-sectional area, designed for connecting distributed speaker systems in commercial PA and public address installations. Each core carries a combination of 25 copper strands and 20 copper-clad aluminium strands at 0.18mm diameter, providing a balance between conductivity and cost across smaller installations. The cable is supplied on a 25m reel with a black PVC sheath and an overall diameter of 7.8mm.

100V line systems step up audio signals to higher voltage and lower current, allowing multiple speakers to be run in parallel over longer cable runs without significant power loss. This 25m reel suits smaller installations such as retail spaces, cafes, small offices and meeting rooms where distributed ceiling speakers or wall-mounted speakers cover one or two zones. The cable supports up to 15A maximum current, which is sufficient for typical small-scale 100V line amplifier outputs in the 50-200W range.

The black PVC sheath protects the conductors during installation in ceiling voids, wall chases and surface-mounted trunking. The 7.8mm diameter is compact enough to fit through standard cable grips and conduit without excessive bending resistance, while still providing adequate protection for the stranded cores. The copper/CCA construction keeps the cable lighter and more flexible than pure copper equivalents at this CSA, which simplifies installation in tight spaces or where multiple cable runs converge at a distribution point.

What is 100V line and why is it used?

100V line (also called constant voltage) is a method of distributing audio where the amplifier steps up the signal to 100V, allowing multiple speakers to be connected in parallel without impedance matching issues. It's used in commercial PA systems because it allows long cable runs and many speakers on one amplifier output with minimal power loss.

What length of cable run does 1.15mm² support?

At 1.15mm² CSA, this cable suits runs up to approximately 25-30m per speaker in typical 100V line installations without significant voltage drop. For longer runs or higher power speakers, a larger CSA cable (2.5mm² or above) would be recommended.

Can this cable be used for low-impedance speaker systems?

Yes, the cable is electrically suitable for 4-16 ohm low-impedance speaker connections, though it's primarily designed and marketed for 100V line use. For low-impedance runs over 10m, a larger CSA is typically preferred to minimise resistance losses.

What's the difference between copper and CCA conductors?

Copper-clad aluminium (CCA) uses an aluminium core with a thin copper coating, making it lighter and cheaper than pure copper. Pure copper has better conductivity and flexibility. This cable combines both in each core to balance cost and performance for typical small PA installations.