Mercury Heavy Duty Figure 8 Speaker Cable 2 x 79 Strand Black - 100m Reel

The Mercury heavy-duty figure 8 speaker cable is a two-core audio cable built from 2 x 79 strands per conductor, combining copper and copper-clad aluminium (CCA) to balance conductivity with flexibility. Each conductor uses 40 strands of 0.18mm copper wire plus 39 strands of 0.18mm CCA wire, giving a combined cross-sectional area of 2.50mm² and a maximum current rating of 25A. The figure 8 profile measures 5.0 x 10.0mm and allows the two conductors to run parallel while remaining easily separable for termination.

Designed for permanent installation in commercial sound systems, live sound rigs, public address systems, and high-power home audio, the cable suits runs from amplifiers to passive loudspeakers where long cable lengths are needed and buying by the 100m reel is more cost-effective than pre-cut lengths. The black PVC sheath resists abrasion during installation and the white polarity line printed on one conductor helps maintain correct phase alignment when terminating multiple speaker runs or wiring multi-speaker arrays.

The hybrid copper/CCA construction keeps the cable lighter and more flexible than solid copper equivalents while retaining sufficient conductivity for typical PA and distributed speaker installations. The 2.50mm² CSA handles impedances down to 4 ohms on runs up to 20-30m without significant power loss, though longer runs or lower impedances may require stepping up to a heavier gauge. The cable is supplied on a 100m plastic reel that protects the cable during storage and allows clean unspooling during installation.

What's the difference between copper and CCA conductors?

CCA (copper-clad aluminium) wire has an aluminium core with a thin copper coating, making it lighter and cheaper than solid copper. Pure copper has better conductivity, so this cable uses a hybrid construction with 40 copper strands and 39 CCA strands per conductor to balance performance, weight and cost. For most PA and home audio runs under 30m at 8 ohms, the difference in sound quality is negligible.

What speaker runs is this cable suitable for?

The 2.50mm² CSA and 25A current rating suit passive loudspeakers on runs up to 20-30m at 8 ohms, or 10-15m at 4 ohms. Typical applications include PA systems in function rooms, distributed ceiling speaker installations, or connecting bookshelf speakers in large domestic rooms. For longer runs or lower impedances, step up to a heavier gauge cable.

What does the polarity line do?

The white line printed on one conductor acts as a polarity marker, helping you maintain consistent phase when wiring multiple speakers. Connecting the marked conductor to the positive terminal on all speakers ensures they move in phase, which is critical for stereo imaging and preventing phase cancellation in multi-speaker arrays.

Can this be buried in walls or installed outdoors?

The black PVC sheath is designed for indoor installation in conduit, trunking or surface-mounted runs. It is not rated for direct burial in walls (which would require cable meeting building regulations for concealed wiring) and is not UV-stabilised for permanent outdoor exposure. For outdoor speaker runs, use outdoor-rated speaker cable or run this cable inside UV-resistant conduit.