Shielded cables are also known as instrument cables.
Instrument cables are shielded because it connects to amplifiers which are high impedance.
For those who don't remember, impedance means resistance. The degree of resistance is measured in ohms.
The lower the impedance, the easier it is for electricity to pass through.
High impedance environments are more prone to circuitry backfiring and damaging the user in the process.
Imagine trying to plug your cable in and the current doesn't match?
You could burn yourself.
Having instrument cables protected protects them from damaging itself.
Not only does it protect its wires, but it also protects against other signals. Interference from radios or other signals are blocked by the shielding.
What helps its signal carry on to an amplifier is a conductor. If there were no shielding to protect it from other signals, it would never make it to the amplifier.
This is a big difference compared to speaker cables.
Unshielded cables are also known as speaker cables.
Speaker cables on the other hand need to have a strong signal.
Do you know why?
It's because they carry sound with it after it has been through the amplifier. The strength of its own signal blocks out other signals nearby.
Having a strong signal lets speaker cables be unshielded.
The reason why instrument cables and speaker cables differ in looks is because of their signal strength. This in turn determines whether it's shielded or unshielded.
But how can we tell the difference between the two?
How To Tell The Difference?
Besides reading the label (highly recommend), you can take a look inside of each cable.
Do this by opening the end of the cable and looking at the wires.
You'll know it's an instrument cable if the wires are covered either by a braided mesh or foil wrap.
If there's no shielding, then you'll know it's a speaker cable.
And The Winner Is...
There is no winner.
It all depends on what situation you're in. In fact, both cables need each other if you're at a concert.
You need the instrument cable to transfer its signal before the speaker cable transmits its signal to the speakers.
If you were to put a speaker cable in place of an instrument cable, you'll get unwanted noise such as buzzing or humming.
There are more dangers like melting of cables, but we don't want to go further into that.
Just know that these cables are completely different.
Make sure you know which one you're dealing with!