If you want a great subwoofer cable, look no further than the AudioQuest SUB-1. This cable features three separate silver-plated solid copper conductors to maximize signal transfer, with each conductor having its own air core insulation layer. All three conductors together are also shielded to effectively eliminate noise, with the shield completely covering the outer sleeve of the RCA connector. The conductors are also sliver-plated copper, and attached with silver paste instead of standard solder. A very nice feature is a separate ground wire which can be connected to further reduce the potential for AC hum.
This cable is a great choice for audiophiles, and it is not insanely priced. The only caveat would be using this subwoofer cable in systems where the equipment is exposed to moisture. The silver-plated copper is electrically superior, but not corrosion resistant like gold.
The Blue Jeans Cable LC-1 is a close second to the AudioQuest SUB-1. Blue Jeans is a small company that makes great products. Their LC-2 cable is quite thick - .30 in diameter, and constructed of low-capacitance copper. Each cable has two separate braided shields, with the shields tightly connected to high quality RCA connectors with gold-plated contact points. Additionally, the Blue Jeans LC-1 is UL listed and CM rated for in-wall applications. These subwoofer cables are made to order in the desired length, and can be further customized as needed. The only negative could be the profile and thickness if you are running this under a carpet.
This audiophile subwoofer cable has all the essentials for a high quality interconnect. Like the Audioquest SUB-1, the Silver Serpent contains silver-plated copper conductors, but these are stranded core instead of solid. Some audiophiles will prefer solid over stranded wire for these applications, but the silver plating still makes this cable a decided upgrade in terms of signal transfer. The rated signal loss is only .3 dB over a 100 ft run - quite impressive. This subwoofer cable has a bare copper shield to minimize noise pick up, and has a very sturdy outer jacket. The Silver Serpent is a good choice to improve the sound of the bottom octave of your system.
The Monster Cable 600SW subwoofer cable is yet another quality subwoofer cable from a company known for their interconnects and speaker wire. The 600SW has two solid-core copper conductors to carry low frequencies with another wire network designed to deliver higher frequencies which, when lost, can result in less defined articulation. Like all quality cables, this subwoofer cable has a shield to reduce EMI and RFI noise. And the flexible outer cover, and gold-plated RCA connectors makes this a useful cable for both home and car applications. This is a product is a typical Monster offering - high-quality and priced within reach.
The last entry in our Best Subwoofer Cable category is not really in the same league as the first three, but it still is a very capable interconnect and a bargain. This Mediabridge subwoofer cable uses a single copper conductor with a double shield system consisting of copper and aluminum along the entire jacket. Aluminum keeps the price down, and works well as a shield at lower frequencies (less so at higher frequencies). Gold-plated RCA connectors finish this nice choice for music lovers on a tight budget. And, unlike most subwoofer cables, the Mediabridge Ultra Series is also perfectly suited to being used as a digital audio or video cable. So if you upgrade later, this will still be a useful interconnect.