Low Volume/Faulty Speaker Cable - Why?

whoatherechunk · #1 06-22-2011, 11:13 PM

Today I had practice with one of my bands and my guitarist was borrowing my Peavey 6505+ (guitard speak...sorry haha). When he started playing it, the volume was super super quiet and very inaudible. I thought perhaps the power tubes had gone out. I tried that same speaker cable on my bass rig and well the same thing occurred. I switched out the speaker cable and everything went back to normal. I disposed of the speaker considering that I have no idea how to repair cables and just wanted to get it out of the way. My question is, what would make a speaker cable do such a thing? Sure cymbals can fall on cables, the integrity of the wiring in a cable can get damaged when bent/kinked, but speaker cables don't usually have these issues (at least not in my case). Could it of been simply a poor quality issue? I'm just wondering why a speaker cable would go out regardless of its age when they've been treated especially well. If it would of had a short, I'm assuming the amp would of been making weird noises but in my case the issue was that the volume was extremelyyyyy dismal.

brendanbassist · #2 06-22-2011, 11:21 PM

If there was a short, it probably would have damaged the amp. More likely is a break in the cable somewhere, or a solder connection at the jack came loose.

nashvillebill · #3 06-22-2011, 11:28 PM

I've had a cable where inside the plug, one of the strands of wire got loose from the solder and started contacting the other conductor, but it was only partially conducting, and got very low volume without snapping and popping.

If it was a tube amp, actually a shorted output is (usually) no big deal. Some tube amps even have shorting output jacks so if you forget to plug in a speaker cab, the output jack will short to avoid damaging the output transformer.

whoatherechunk · #4 06-22-2011, 11:35 PM

right on. well thanks for the educational info guys. i'm assuming that most people just toss the cables and dont deal with the hassle of re-soldering the speaker cable? (not that im even going to attempt doing that haha)

will33 · #5 06-23-2011, 01:22 AM

That's fine but don't throw it away, give it to somebody. 5-10 minutes and a dab of solder and they've got a brand new cable while you're out wasting your money on another one. IMO, if you're not making your own cables you're spending waaaayyy too much.

starmoon · #6 06-23-2011, 01:29 AM

Yup, don't throw it away.

billfitzmaurice · #7 06-23-2011, 07:02 AM

Quote:

Originally Posted by nashvillebill

I've had a cable where inside the plug, one of the strands of wire got loose from the solder and started contacting the other conductor, but it was only partially conducting, and got very low volume without snapping and popping.

+1. That can pass just enough current to cause a volume loss but not enough to kill the output completely and/or cause the amp to shut down.

whoatherechunk · #8 06-23-2011, 08:14 AM

so if it's a wire in the cable itself how would you know where to splice the cable? i will keep the cable and maybe do some work on it myself. haha

nashvillebill · #9 06-23-2011, 08:30 AM

If it's a wire strand partially shorting like my example, it would be in one of the plug ends. No need to cut or splice anything if the plugs are the typical type where you unscrew the barrel of the plug, then you have access to the soldered connections. Check there first. It's highly unlikely the wire itself has a short--usually when a wire fails, its from breakage.

So let me back up and explain the difference. A circuit requires two wires (conductors). A broken wire or open solder connection causes an OPEN circuit. Electricity cannot flow. This is like a garden hose that you've put a kink into, the water shuts off because the kink is a stoppage, where water cannot be conducted. In the case of intermittent OPEN wires (like a break in an instrument cable) the wire works sometimes but not others, I've almost always noted snapping and crackling then. An open wire or connection, if tested with an ohmeter, measures infinite resistance.

A SHORT occurs when electricity can flow from one conductor (wire) to the other. Like a garden hose with a small hole in it, some of the water can flow out of the hose. (best analogy I can think of this early in the morning). A short between two wires, if tested with an ohmeter, will show a resistance much closer to zero than to infinite (if one strand is scraping against the other part of the plug, it might be anywhere from zero to a few ohms on the meter). Incidentally this is measured by putting one meter probe on one wire and the other probe on the other wire.

Again, take the barrel off the plugs and look at the soldered connections. The wires should be nice and neat going into each solder joint, no frizzy little hairs (strands) poking out. Note that inside the barrel there is likely a plastic or cardboard insulating tube, make sure it is in place when screwing the barrel back on.

Bassamatic · #10 06-23-2011, 08:46 AM

While the problem MAY be in the plug, it could also be in one of the conductors of the cable, especially if it has been twisted or handled roughly, run over by carts, etc. As said - it is probably not a short, but most of the strands of the wire could be broken, with just a little bit passing a tiny bit of current. I had this happen with a guitar cable.

Finding the broken part inside a cable is nearly impossible. Time to replace it. Remove the ends and get a piece of 16 Ga. AC cord - very cheap.

UH - You are not using a guitar cable for your speaker, right? The conductors are way to small to begin with.

whoatherechunk · #11 06-23-2011, 11:12 AM

thanks for the tips guys. i will check the cable when i get home. and i was definitely not using a guitar cable. super thick speaker cable indeed.