What is the difference between a speaker cable and an instrument cable?
Instrument cables are designed to work in high-impedance environments. This means that it goes from a device with a high output impedance, such as electric guitars, into an amplifier or other device that has a high resistance. They generally move very little current and are usually constructed of a single center conductor and a shield. Instrument cables by nature are susceptible to electrical interference, but most use some sort of shielding to help keep noise out.
Speaker cables are designed to work in low-impedance environments - the opposite of instrument cables. This means that it connects a low impedance output of a device like an amplifier to a low impedance of a speaker. Shielding is not critical for a speaker cable because it is not very susceptible to noise because of low impedance, their general construction of twisted pair, and because of the higher levels of signal that they move.
To be as general as possible, instrument cables connect an instrument to an amplifier and speaker cables connect amplifiers to passive loudspeakers.
So, can I use an instrument cable as a speaker cable?
Although technically it could work, DON'T DO IT! Using an instrument cable in place of a speaker cable can severely and permanently damage your amplifier! It can burn up your amplifier, especially a tube amp! In addition to the risk of destroying your amp, you could also have significant signal loss due to smaller conductors in instrument cables. Instrument cables are typically 20 - 24 gauge conductors and speaker cables are generally 12 - 16 gauge (remember the higher the gauge, the thinner the wire). Thinner wire has more resistance adding more load to the amp and causing the wire to heat up and even "burn up" sometimes. Now, using a speaker cable as an instrument cable won't technically harm anything; However, it will almost always inject lots of noise and make your high impedance instrument sound horrible. I would strongly suggest not using a speaker cable as an instrument cable, and I would definitely recommend that you never use an instrument cable as a speaker cable. Use the cables for the application that they are intended!
Remember, just because a cable is more expensive doesn't necessarily make it a better cable! Some companies get greedy and don't have your best interest in mind and will sell you on reasons why their $50 cable is better than a $10 cable. More expensive doesn't always equal better!
- 1/4" - Used for instrument cables, speaker cables, patch cables, and most input and output for speakers, floor monitors, mixers, and other pro audio devices
- XLR - Used for sending balanced signals, most common connector for microphones
- Banana Plug - Primarily used for connecting amplifiers to speakers
- Speakon - a relatively new type of connector that locks in place, is very rugged, and is used for sending a powered signal from an amplifier to a passive speaker or floor monitor