Don’t get us wrong– we love repairing your gear. But there are some common mistakes we see over and over again that are so easily preventable it kills us. Today’s lesson should provide a little guidance in Not Breaking Your Own Stuff 101.
Lots of folks take a look at a cable with 1/4″ phone plugs on each end and see a dual-purpose speaker and instrument cable. However, pick the wrong cable for the application and yes, it will plug in, and it will even work (ish), but best case scenario it will not perform well and worst case it’ll catch your output transformer on fire. We’ll be happy to fix that for you, but why not save yourself the surprise of a blowout mid-gig and let us fix the really interesting (read: confusing) issues that are bound to occur all on their own.
So what’s the difference between speaker and instrument cables, and how can you tell?
An instrument cable is coaxial. That means there is just one small diameter center conductor. That’s all you need to transmit the low power signal from your instrument to your amp. Your amp then boosts that signal to a usable level. This center wire is encased by a braided shield conductor and insulators that keep that small, sensitive signal from experiencing any interference. An instrument cable will often be smaller, lightweight, and more flexible than a speaker cable, but some are beefed up with tweedy covers or other accoutrement that confuse their application. Sometimes there is a helpful identifying mark– such as the word “instrument” printed on the cable jacket. Speaker cables are usually marked as such while instrument cables may or may not have an indication as to their application.
Now that you know what an instrument cable is– DO NO USE IT FROM YOUR AMP TO YOUR SPEAKER! I don’t care what your band mate says– it will not sound awesome. You may not notice much badness at low levels, but once you crank it, all the power coming out of the amp can’t make it through that little instrument cable, so its going to turn into hot heat. You can probably guess that electrical heat can be a bit of a safety concern, plus you’re working your poor output transformer (you are playing a tube amp, right?) to death.
A speaker cable needs to transmit a lot more power than an instrument cable. Generally, it’ll have two equal gauge wire conductors (as opposed to one signal wire and a shield) and the wires will be beefier.
Using your speaker cable for your instrument isn’t so much of a fire hazard, it’ll just hum like crazy. The reason for this is that, as you may recall if you’ve been taking notes, the instrument cable is well insulated, because the sensitive little conductor easily picks up outside interference. The speaker cable is left unshielded, so when you plug it into your guitar you’ll get buzzing from the fluorescent lights, other power supplies, and swarms of electric killer bees. If you want overdrive and distortion, this is not the way to get it.
Take five seconds to figure out what kind of cable is in your hand, and use them correctly– you will be rewarded for your diligence with more massive rocking potential.
Thanks for tuning in. Oh yeah, and we have lots of appropriate cables in store, so no excuses.