# Speaker Vs Instrument (Guitar) cables



## Anonymous067 (Jan 4, 2011)

Yes, they're both 1/4" and unbalanced. But you really shouldn't use them interchangeably.

What other argument points besides...

Instrument cable cannot handle the power and heat buildup going through them from a power amp. Instrument cable is braided shield, speaker cable is two conductor unshielded (usually...).

What else?


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## MisterTim (Jan 4, 2011)

Anonymous067 said:


> Yes, they're both 1/4" and unbalanced. But you really shouldn't use them interchangeably.
> 
> What other argument points besides...
> 
> ...


 
Instrument cable isn't necessarily a braided shield, it's just shielded. 

Speaker cable is 2 conductors, instrument cable is 1 conductor and a grounded shield. They're just different.  

Why do you need arguments for this?


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## jeffsw6 (Jan 4, 2011)

Anonymous067 said:


> What else?


 Ever haul 30 feet of 12/2 cable around by your guitar all night? Would you want to when you could use a more appropriate cable? Heck no!


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## MisterTim (Jan 4, 2011)

jeffsw6 said:


> Ever haul 30 feet of 12/2 cable around by your guitar all night? Would you want to when you could use a more appropriate cable? Heck no!



I'm going to make myself a 12/2 SOOW instrument cable now that you say that and stick it in my bass guitar case just so people can stare at me.


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## TheGuruat12 (Jan 4, 2011)

MisterTim said:


> I'm going to make myself a 12/2 SOOW instrument cable now that you say that and stick it in my bass guitar case just so people can stare at me.


 
Is genius! Might make myself a couple to make the jazz band grumble.


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## Anonymous067 (Jan 4, 2011)

MisterTim said:


> Instrument cable isn't necessarily a braided shield, it's just shielded.
> 
> Speaker cable is 2 conductors, instrument cable is 1 conductor and a grounded shield. They're just different.
> 
> Why do you need arguments for this?


 
Trying to educate the high ups about purchasing decisions.


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## jeffsw6 (Jan 4, 2011)

Anonymous067 said:


> Trying to educate the high ups about purchasing decisions.


 Do musicians ever unplug their guitars before the channel/rig is muted, and produce a popping sound through the PA? If you think that could be a way to get your bosses to approve funds for guitar cords, I suggest these handy cables with special Neutrik connectors: GBNC-SILENT also available in right-angle version

If you are owning guitar cables for lending to musicians, be sure you label them very effectively and remember to collect them at the end of the gig.


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## avkid (Jan 4, 2011)

Anonymous067 said:


> Instrument cable cannot handle the power and *heat buildup *going through them from a power amp.


 So why didn't my wedge cables melt for all those years?


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## jeffsw6 (Jan 5, 2011)

avkid said:


> So why didn't my wedge cables melt for all those years?


 For the same reason that a 1000w PAR can won't melt a 16awg extension cord -- the RMS draw through the cable is insufficient to actually damage it or cause a fire. That doesn't mean it's a good idea.

Of course, a typical 22AWG instrument cable is intended for 1 amp or less, and will melt almost instantly with 40 amps. At some point between those two current values, the conductor insulation will catch on fire.

Also, damping factor of the amplifier/loudspeaker system is influenced significantly by the speaker cable.

If your monitors are run at fairly quiet levels, sure, a 22awg cable is probably not a hazard and does not audibly affect the system performance.

If you are like me, and are sometimes running 4Ω monitor circuits at 500w RMS (measured drive level, with amp into limiter and signal hovering between -6dB and -3dB from 1000w peak limit) then you can turn to Ohm's Law and find that your monitor speaker cable is probably carrying around 8 amps of current. You can then figure the temperature rise and resistance change of the 22AWG cable to find that the cable would ultimately be heated to about 130C, which would ignite the insulation, but will not be hot enough to melt the conductor itself, so if they don't short together and trip fault protection in the amplifier, the conductors will sustain a fire.

This is how electrical fires happen. Using instrument cables for loudspeakers is stupid. Why take a chance?


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## epimetheus (Jan 5, 2011)

jeffsw6 said:


> For the same reason that a 1000w PAR can won't melt a 16awg extension cord -- the RMS draw through the cable is insufficient to actually damage it or cause a fire. That doesn't mean it's a good idea.
> 
> Of course, a typical 22AWG instrument cable is intended for 1 amp or less, and will melt almost instantly with 40 amps. At some point between those two current values, the conductor insulation will catch on fire.
> 
> ...


 
I'm pretty sure most cable insulation is flame retardant. While it may melt and allow the conductor to short and thus spark causing a fire, I don't think the insulation will spontaneously ignite. Somebody correct me if I'm wrong here and, if possible, provide a source of your information.


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## jeffsw6 (Jan 5, 2011)

epimetheus said:


> I'm pretty sure most cable insulation is flame retardant. While it may melt and allow the conductor to short and thus spark causing a fire, I don't think the insulation will spontaneously ignite. Somebody correct me if I'm wrong here and, if possible, provide a source of your information.


Most things will ignite if you get them hot enough, including electrical cable insulation. This is why cable insulation has a design temperature rating that should not be exceeded, and why you must de-rate conductors in high ambient temperature environments, depending on insulation temperature rating, to prevent cable damage or catastrophic fire.

If you need a source for this information, pick up a copy of the NEC, or read the outer jacket on different cable stock. Insulators are commonly rated for e.g. 60C 75C 90C and so on. There are de-rating tables and formulas in the NEC and its annexes.


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## epimetheus (Jan 5, 2011)

jeffsw6 said:


> Most things will ignite if you get them hot enough, including electrical cable insulation. This is why cable insulation has a design temperature rating that should not be exceeded, and why you must de-rate conductors in high ambient temperature environments, depending on insulation temperature rating, to prevent cable damage or catastrophic fire.
> 
> If you need a source for this information, pick up a copy of the NEC, or read the outer jacket on different cable stock. Insulators are commonly rated for e.g. 60C 75C 90C and so on. There are de-rating tables and formulas in the NEC and its annexes.


 
I'm very well aware on the temperature rating on conductors, I use the NEC on almost a daily basis (my day job is electrical substation design). The conductor temperature rating is not the temperature above which it will ignite though. It means the conductor will properly function at or below that temperature indefinitely. I'm not debating that a cable run hotter than it is rated for will fail, it will, eventually. I'm arguing that the insulation wont combust on its own.


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## jeffsw6 (Jan 5, 2011)

epimetheus said:


> I'm very well aware on the temperature rating on conductors, I use the NEC on almost a daily basis (my day job is electrical substation design). The conductor temperature rating is not the temperature above which it will ignite though. It means the conductor will properly function at or below that temperature indefinitely. I'm not debating that a cable run hotter than it is rated for will fail, it will, eventually. I'm arguing that the insulation wont combust on its own.


 Well, if you are making that as a blanket statement about all electrical cable insulation, you are wrong. TPE will burn readily. Most cables with an MHSA approval for use in mines will not. Consider also that the cable may be in contact with other materials that could ignite.

Since you are in the electrical power industry, you are probably at least aware of old-style "knob and tube" wiring, with no insulator. Electricians involved in removing that crap from old buildings often note that, in some respects, it is safer than modern cable, precisely because it does not have an insulator that retains heat and can be an ignition source.


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## epimetheus (Jan 5, 2011)

jeffsw6 said:


> Well, if you are making that as a blanket statement about all electrical cable insulation, you are wrong. TPE will burn readily. Most cables with an MHSA approval for use in mines will not. Consider also that the cable may be in contact with other materials that could ignite.
> 
> Since you are in the electrical power industry, you are probably at least aware of old-style "knob and tube" wiring, with no insulator. Electricians involved in removing that crap from old buildings often note that, in some respects, it is safer than modern cable, precisely because it does not have an insulator that retains heat and can be an ignition source.


 
I was referring to the topic at hand, speaker and instrument cables. I'm not talking about power cable or any other type of cable. Are you saying that if you overloaded a speaker or instrument cable to the point of failure, the insulation would catch fire? That's all I'm trying to figure out here. I'm pretty darn sure it wont, but enlighten me.


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## MisterTim (Jan 5, 2011)

jeffsw6 said:


> If you think that could be a way to get your bosses to approve funds for guitar cords, I suggest these handy cables with special Neutrik connectors: GBNC-SILENT also available in right-angle version.


 These are awesome connectors, but don't pay that terrible price for them, just buy the connectors and bulk cable and make them yourself. It's $12 in parts for a silent 6' instrument cable. This is what I use on my (real) guitar cables, on Mogami W2524. 

I've seen EWI mentioned quite a few times on here, but I don't know why, because every time I've looked, their prices are awful.


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## avkid (Jan 5, 2011)

MisterTim said:


> I've seen EWI mentioned quite a few times on here, but I don't know why, because every time I've looked, their prices are awful.


 As compared to what?

Audiopile Products


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## MisterTim (Jan 5, 2011)

avkid said:


> As compared to what?
> 
> Audiopile Products



I generally use Redco for this type of stuff. 

Here's the price for an Neutrik NL4MP 


(because that's what's on my brain):

Redco: $1.98
Markertek: $2.06
Amazon: $2.19
Parts Express: $2.19
FullCompass: $2.58
Mouser: $2.70
MCM: $2.99
Audiopile: $3.00 
AudioGear: $3.25
Sweetwater: $4.19
MusiciansFriend: $4.46
Zzounds: $4.95
B&H: $4.95
GuitarCenter: $6.99

Okay, so they're not as bad as I thought, I'm just spoiled by Redco + 25% academic discount + free shipping. But seriously, every time I've looked, Redco has the best prices on connectors and bulk cabling. Great service, too.


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## jeffsw6 (Jan 5, 2011)

epimetheus said:


> I was referring to the topic at hand, speaker and instrument cables. I'm not talking about power cable or any other type of cable. Are you saying that if you overloaded a speaker or instrument cable to the point of failure, the insulation would catch fire? That's all I'm trying to figure out here. I'm pretty darn sure it wont, but enlighten me.


It depends on what type of insulation is on the cable. That is why I say TPE will burn and MHSA-approved cables won't. Copper is copper, but there are many different kinds of insulation. This really isn't a cut-and-dry yes/no. It is a case of, anyone using a 22AWG instrument cable as a speaker cable is careless and negligent, and should not be doing that given the low cost of suitable speaker cables compared to everything else we deal with.


MisterTim said:


> I've seen EWI mentioned quite a few times on here, but I don't know why, because every time I've looked, their prices are awful.


 It depends on what you are buying. I will admit to not having done any shopping around for similar silent guitar cables before posting that link, though; I just wanted to give the OP another idea of how he might gain approval for buying instrument cables.


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## epimetheus (Jan 5, 2011)

jeffsw6 said:


> It is a case of, anyone using a 22AWG instrument cable as a speaker cable is careless and negligent, and should not be doing that given the low cost of suitable speaker cables compared to everything else we deal with.



Sometimes the world just doesn't work this way. If the system works with 5 hot spots connected to one amp channel with instrument cables, it's quite difficult to convince the person who's responsible for the budget to change it.

Related to the silent 1/4" connectors, I don't like them. That's one more connection to go bad. Cables get beat to crap, especially instrument cables, in my experience. And now you want to put a reed switch in the mix? No thanks. I'll keep beating the crap out of the artists until they mute before unplugging.


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## headcrab (Jan 6, 2011)

Show the higher-ups a speaker cabinet that has only Speakon connectors.


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## WooferHound (Jan 7, 2011)

A Speaker cable and an Instrument cable can not be used interchangeably. 

Instrument/Mic cable carries signals that are millivolts and do not need heavy conductors. They need to be shielded to keep out electrical interference. They need to be flexible because instruments and mics move around a lot.

Speaker cables carry High Voltage and High Current and need to be a thick heavy gauge wire. Amplifiers have a Damping Factor which controls the speaker from ringing or over extending the cone. This damping works by using Low resistance and the wiring needs to be very low resistance to provide optimum damping to the speaker. For Full Range or Bass speakers it is best to use 12ga or even 10ga speaker wire to maintain good damping which lets the speaker produce a deeper tighter more pleasant sounding Bass Note. A speaker wire should not be shielded because this creates unwanted capacitance which interacts with the high voltages and degrades the signal, outside electrical interference is not a problem with speaker systems.


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## DuckJordan (Jan 7, 2011)

WooferHound said:


> A Speaker cable and an Instrument cable can not be used interchangeably.
> 
> Instrument/Mic cable carries signals that are millivolts and do not need heavy conductors. They need to be shielded to keep out electrical interference. They need to be flexible because instruments and mics move around a lot.
> 
> Speaker cables carry High Voltage and High Current and need to be a thick heavy gauge wire. Amplifiers have a Damping Factor which controls the speaker from ringing or over extending the cone. This damping works by using Low resistance and the wiring needs to be very low resistance to provide optimum damping to the speaker. For Full Range or Bass speakers it is best to use 12ga or even 10ga speaker wire to maintain good damping which lets the speaker produce a deeper tighter more pleasant sounding Bass Note. A speaker wire should not be shielded because this creates unwanted capacitance which interacts with the high voltages and degrades the signal, outside electrical interference is not a problem with speaker systems.



Not to muddy the waters at all but this is for my own use, What about going from a board to a powered speaker? is it okay to use an instrument cable instead of a speaker cable?


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## bishopthomas (Jan 7, 2011)

DuckJordan said:


> Not to muddy the waters at all but this is for my own use, What about going from a board to a powered speaker? is it okay to use an instrument cable instead of a speaker cable?


 
It would be best to keep it balanced (if using 1/4" then TRS), but an instrument cable will work just fine (disclaimer: most of the time). You actually DON'T want speaker cable in this scenario because it is not shielded.


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## WooferHound (Jan 7, 2011)

Instrument/Mic cables are used *before* the Amplifier
Speaker cables are used *after* the Amplifier

The amplifier is inside the powered speaker so the speaker wires are permanently hooked up inside the cabinet. Preferably, you would want to use microphone cables to send a signal to your powered speakers.


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## bishopthomas (Jan 7, 2011)

MisterTim said:


> I've seen EWI mentioned quite a few times on here, but I don't know why, because every time I've looked, their prices are awful.


 
I've never priced their raw cabling and connectors (I buy from Redco, Markertek, and CBI) but for cases you can't beat them for "bang for the buck."


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## bishopthomas (Jan 7, 2011)

WooferHound said:


> Preferably, you would want to use microphone cables to send a signal to your powered speakers.


 
"Microphone cables" meaning a twisted pair with shield. The connectors you use are irrelevant (assuming they allow for positive, negative, and ground termination).


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## avkid (Jan 7, 2011)

Read this:
http://www.bennettprescott.com/downloads/dampingfactor.pdf


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## epimetheus (Jan 7, 2011)

headcrab said:


> Show the higher-ups a speaker cabinet that has only Speakon connectors.


 
Not a very useful post. First, my post said hot spots. Find me a hot spot with only speakons. Second, what about speakon to 1/4" adapters?

My point is just that we don't always get to design and operate our systems in an ideal state. We should always strive for that, but you have to be realistic in the real world.


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