Best gauge of speaker wire

[Milspec]

Need some quick history and education here about the proper wire gauge for a speaker cabinet.

Well, acutally, it might be a few specific questions:

1. What guage did Fender use up through the black face era to wire the speakers?
2. What is the ideal gauge for amps below 50 watts in a speaker cab?
3. Is strand better than solid copper wire and if so, why?

I am loading my Bandmaster cab with a pair of Altec 417-8C speakers that I had in a couple of 1x12 cabs. The Altecs do not use blade connectors, it has wire nuts so I need to make some alterations to all the cabs. I was just going to make some extension pigtails with each type of ends so that I can move speakers between cabs if desired later, but now I think I just want to re-wire them.

The 1x12 cabs are getting a re-coned Oxford from a Twin Reverb I have in the closet and maybe the Alessandro speaker...still playing with that plan, but it all starts with re-wiring the jacks to the same gauge for simplicity.

I do have a spool of 14 g. multi-strand speaker wire on the bench, but at less than 40 watt and the short run of wire, that seems over-kill. I don't know if it would make any difference, but that is why I ask the questions.

 

[Blue Bill]

Don't know about Fender's official gauge.

The electrical qualities of a length of wire are directly proportional to the length of the wire. Therefore, for the 12 to 20 inch length of the speaker hook-up lead in an amp, things like resistance, capacitance, skin-effect, inductance, etc, are tiny enough to be insignificant. 16 ga is fine. Most people go for a beefier gauge, I guess because it looks more robust.

Stranded wire is preferred because it provides many more mechanical contact points where it attaches to the connectors. Solid wire may only touch the connector surfaces in 2 or 3 places, making it more susceptible to corrosion problems over time.

Send us a picture.

 

[King Fan]

I'll be interested to see what folks find in their vintage amps, and what engineering formulas suggest for these short runs. Pics I've seen suggest the vintage stuff was not stout.

 

[printer2]

I would use 16-18 gauge wire, lamp chord wire would be more than adequate. I would not think twice about using up to 22 gauge if I did not have any 18 gauge lying around. For a bass cabinet with two 15's with 400W feeding them I would not go less than 18 gauge, for a 50W amp the smaller wire size can handle the current. Stranded of course.

 

[Blue Bill]

One consideration is that thinner wire is easier to break, especially if the amp will be used at gigs. I tend to store cables, pedals, and footswitches in the back, and the speaker wire may take a hit or two.

 

[PCollen]

Need some quick history and education here about the proper wire gauge for a speaker cabinet.

you can use simple zip-cord speaker wire, similar to lamp-cord , or spooled stranded wire in a gauge that will handle the expected current, which depends on expected max power and load as follows:

Power = Voltage x Current = I x R x I = I^2 x R.

For a 50 watt amp with a 4 ohm load: I^2 = 50/4 = 12.5 amps.
So the current I is 12.5 ^1/2 = 3.55 A . You will need a wire gauge that can carry a min. 3.55A current load, or 4 A to add a margin of safety. 18, 16, or your 14 ga. stranded wire will work just fine.

AWG - American Wire Gauge Current Ratings

Amp ratings vs. US AWG wire gauges.

www.engineeringtoolbox.com

 

[schmee]

16 gage is fine. I would say that is close to what Fender used. Maybe 18 gage.
Nothing wrong with 124 gage. I like to tin/solder the ends for JBL, Altec, EV mechanical connectors so the strands stay together.
Stranded wire is flexible and wont break due to movement so use that ...NOT SOLID for this application.
The length is so short in a combo cab that 16/18 ga is plenty. The longer the wire the heavier it needs to be to prevent loss. But at 2 ft or less it irrelevant.

 

[CCK1]

14 gauge is plenty heavy enough, even 16 or 18 would be fine. Stranded is preferable due to it's flexibility.

 

[King Fan]

I'm sure 14ga would work, but is it needed in a speaker cab? That AWG table seems to say at even 22ga could handle up to 3A and 20ga could handle up to 5A in up to triple conductor runs. According to the site listed above, you could wire your house with 14ga; the NEC guide says 14ga has an ampacity (yeah, amp capacity) of 20-25 in runs of up to 3 conductors.

No argument against using 14ga if it's what you have on hand, but I'm pretty sure the common working standards (like lamp cord) are no bigger than 18ga. And that's for a 50W amp...

 

[Milspec]

I'm sure 14ga would work, but is it needed in a speaker cab? That AWG table seems to say at even 22ga could handle up to 3A and 20ga could handle up to 5A in up to triple conductor runs. According to the site listed above, you could wire your house with 14ga; the NEC guide says 14ga has an ampacity (yeah, amp capacity) of 20-25 in runs of up to 3 conductors.

No argument against using 14ga if it's what you have on hand, but I'm pretty sure the common working standards (like lamp cord) are no bigger than 18ga. And that's for a 50W amp...

Yes, I figured it was over-kill. I looked online at wiring kits for cabs and the first one I found claimed 14 g. so I just went to the shop to see if I had any. It looks like no greater than 18 g in one of my cabs so I was scratching my head as to what I might be missing here?

Same goes for the solid vs stranded question. I know the military insists on stranded because a solid wire can break and lose all connection while stranded can have some breakage yet still be connected, but most vintage amps I have see used solid wire throughout, so again I wondered what I was missing?

I just like to do things according industry best practices when I can.

 

[peteb]

I see small wire, connecting to smaller wire in the speaker.

 

[Telekarster]

Altec 417-8C speakers

I was just going to make some extension pigtails with each type of ends so that I can move speakers between cabs if desired later, but now I think I just want to re-wire them.

Great speakers man! FWIW, and as others have said, I just used some 18 ga that was formerly a power cord from an electric heater that had gone dead. For my Altec, EVM's, etc. I built a pigtail about 4-5" long, so I can swap between hookup types, and soldered both sides i.e. soldered the spade in addition to crimping it on, and tinned the stranded end to keep em nice.

 

[old wrench]

The 14ga wire you have is, as you suspect, over-kill - but using it doesn't hurt anything at all, except for your wallet

14ga wire is good for 15 amps at 120 volts - it will carry a lot of power

The smaller Fender and Ampeg amps of my youth (1960s) used some pretty skinny lamp-cord - like about 18ga

I knew very little about amps back then, but I built speaker cabs and swapped out a fair number of speakers

All of the speakers I ever encountered used stranded wire - some of the audiophiles insist on using wire with a high strand count of oxygen-free copper - but for us guitar players, regular old lamp-cord works just fine - it will transmit the tone

.

 

[monkeybanana]

Stranded!

 

[Milspec]

Great speakers man! FWIW, and as others have said, I just used some 18 ga that was formerly a power cord from an electric heater that had gone dead. For my Altec, EVM's, etc. I built a pigtail about 4-5" long, so I can swap between hookup types, and soldered both sides i.e. soldered the spade in addition to crimping it on, and tinned the stranded end to keep em nice.

I might re-visit the pigtail plan...just need to match wire gauges I guess.

 

[uriah1]

Twisted pair big butt wire.

 

[NoTeleBob]

All of the speakers I ever encountered used stranded wire - some of the audiophiles insist on using wire with a high strand count of oxygen-free copper - but for us guitar players, regular old lamp-cord works just fine - it will transmit the tone

.

I always feel obligated to point out that oxygen-free copper is complete BS

 

[Dacious]

I always feel obligated to point out that oxygen-free copper is complete BS

Especially in Australia where the copper is exceptionally pure......

It might make a difference in 200 ft of surround sound wiring in your home theatre but in 2 feet of speaker wire in a guitar amp where it's already distorted - nyet.

 

[NoTeleBob]

Especially in Australia where the copper is exceptionally pure......

It might make a difference in 200 ft of surround sound wiring in your home theatre but in 2 feet of speaker wire in a guitar amp where it's already distorted - nyet.

No, it won't even make a difference in 200' of wire. Maybe 200,000 feet in a super-collider project. Otherwise, no.

 

[plumcrazyfx]

When you get too big, it won't fit through the holes in the tabs of your jacks. At that point you lose the mechanical connection of a wire through the jack and are relying only on the solder to hold the wire in place and solder ain't glue. Better long-term reliability in heavy use and moving around if you can solder a good mechanical joint in the first place.