For most people buying cable, all that's required is to follow three simple rules.
1. Buy decent quality materials. In this case, it means 100% copper; oxygen free if you like, it doesn't make a huge difference to the cost
2. Get advice on the appropriate thickness for the cable length
3. Stick with a multi-strand cable, somewhere between 30 and 80 strands should work fine
The stuff to avoid is anything where you see it described as CCA or CCS. The abbreviations stand for Copper Coated Aluminium and Copper Coated Steel. It's a favourite trick of unscrupulous sellers. The product looks like copper from the outside, but that's only a very thin anodised layer. The price seems attractive, but in reality you're buying a poor quality substitute. The bulk of your speaker's current is being carried by something that isn't copper.
Also, pass on anything with hundreds of filaments. It's more lossy.
Some will recommend solid core wire - usually mains cable - for speaker duties. I ran it when it came in to fashion in the 80s. It sort of made sense then because copper mains cable was relatively cheap compared to even basic speaker cable. There just weren't that many companies making speaker cable to drive the costs down. That's not the situation any longer. At entry-level pricing, an all-copper speaker cable is competitively priced enough that struggling with stiff and ugly mains cable is a bit of a masochistic choice.
The job that speaker cable has to do is to carry current with the minimum amount of loss, and not to do anything to change the sound in a noticeable way. The current is the energy used in turning an electrical signal in to sound. We all know a little bit about energy conservation. When it comes to speaker cable, longer wires build up more resistance, but thicker conductors reduce the resistance. That means with any speaker cable requirement, there's a sweet spot where the thickness and cost justifies the power saved compared to buying a more powerful (and more expensive) amp.
Standard thicknesses for speaker cable are 1.0mm, 1.5, 2.5, and 4.0mm. If we take a 50W amplifier rated for an 8 Ohm load, and match that with an 8 Ohm speaker of reasonable efficiency (87-90dB/W/m), then compare the power losses for a 30m cable run, and then for a 15m run, we get
50W @ 30m
1.0mm - 21% loss (to 39.5W)
1.5mm - 14% loss (to 43.0W)
2.5mm - 9% loss (to 45.5W)
4.0mm - 6% loss (to 47.0W)
50W @ 15m
1.0mm - 11% loss (to 44.3W)
1.5mm - 7% loss (to 46.3W)
2.5mm - 5% loss (to 47.5W)
4.0mm - 3% loss (to 48.5W)
Once you start to see the effect of thickness versus distance then it's easier to work out what to spend on.
At the longer distance, the 1.0mm cable throws away a 1/5th of the amplifier power. Upgrading to a 2.5mm cable more than halves the losses. That's a worthwhile gain. A 4.0mm cable is overkill at this distance.
At a shorter distance of 15m the cable doesn't need to be as thick. The 1.0mm cable still loses the most, but now the loss is roughly half of what it was at 30m. That's because the losses are proportional to the length: Halve the distance to halve the loss. Double the distance to double the loss.
For a 15m run, there's a worthwhile reduction in the power loss going for a 1.5mm cable, but it's less significant on the thicker lengths. 1.5mm will do fine. The extra cost of a 2.5mm cable isn't worth it over the 1.5mm.
Works perfectly fine for me, and the sound is amazing - nt sure I'd be able to discern between what I have now, and more expensive cabling.
