Speaker Cable - What size do you need?

[Chienmortbb]

As a cable maker I often get requests for 4mm speaker cable to connect heads to cabinets, usually 0.5-1m in length. I always advise that this is both expensive and unnecessary. Here is my explanation. 

 

The reason thinner cable is OK for shorter lengths is the lower resistance/impedance. The current carrying capacity becomes the most important here as over 0.5-1m it is irrelevant for most cable CSAs. I always argues that 4mm is way overspec'd for bass heads to bass cab connection. The cable current carrying capacity is far higher than even the speakOn connectors and the output of bass amplifiers.

 

1mm = 10A

1.5mm = 16A

2.5mm = 25A

4.0mm =  32A

 

10A at 4 ohms = 400 watts

16A at 4  ohms = 1024 watts

25A at 4 ohms = 2500 watts

32A at 4 ohms =4096 watts

 

If your load is 8 ohms the power limit is twice those figures and remember that these are continuous ratings at 25C.

 

If you  look at Sommer Meridian Mobile speaker cable, the resistance is 7.5 ohms per kilometre or 1000 meters. So the resistance is less than 8/1000s of an ohm. So of 2500 watts you would dissipate just under 5 watts in the cable of 1 metre. Of course none of us are using 2500 watt amps...

 

4mm cable was is useful for those massive line array PA systems but not useful for bass amps IMHO. So why do I recommend 2.5mm and why not mains flex of the same size  and rating? 

 

Well I have it in stock. However the real reason is that the Sommer Meridian Mobile cable 2.5mm is very flexible, unlike either mains cable or many competitors speaker cables. Sommer use 140 strands of copper while some well known competitors use 50 in their 2.5mm cable. So they bend more easily and are a delight to use.

 

 

[itu]

Everything @Chienmortbb wrote, was good stuff. Here's my tiny addition.

 

A touring bassist makes easily 100 gigs = 200 dis-/connections yearly to the cab and the amp. If that cable is bent a lot, it means that the strands will be cut = the cable ages and deteriorates. Therefore some extra diameter does not harm. But if the cables are quality and handled decently, their age can be decades.

[Chienmortbb]

I do agree, in my opinion Van Damme Studio, the Blue one is the worst. It is stiffer than most power cables. To be fair to Van Damme, it is designed for Studio installations. As the name implies. However many sellers on eBay sell it for use between heads and cabs.