Does size matter?

[thebrig]

 Does it matter what size cables are used when connecting a cab to the head?
 
 The reason I ask is because I use a KLOTZ 4mm² Speakon Speaker Lead 2 Core Extra High Power NL4FX LY240 cable to connect my head to my cab, but I now want to connect a second cab, so should I use the same size cable (ie, 4mm²) or would a smaller cable (ie, 2.5mm²) be sufficient?

 

I have to admit that the chunky 4mm² cable gives me confidence when playing live gigs.

 

So apart from size, are there really any real differences in performance and durability that justifies spending the extra money on a substantial cable?

Edited May 5 by thebrig

[tauzero]

Performance - no, you just need something with negligible resistance. Durability - probably not, it's the connectors that need to be decent quality. A length of twin core mains cable would do you and would be as durable as something for which you pay rather more.

[PaulThePlug]

12 minutes ago, tauzero said:

A length of twin core mains cable would do you and would be as durable as something for which you pay rather more.

Ah... back in the day me and mates when on a budget would use heavy twin and earth for Hi Fi Speaker cable to great effect

 

As you already have a quality 1st cable, i'd go with a matching second...

Bit of mechanical durability provided my a thicker cable never goes a miss...

 

Build in confidence...

Edited May 5 by PaulThePlug

[Bill Fitzmaurice]

2 hours ago, thebrig said:

So apart from size, are there really any real differences in performance and durability that justifies spending the extra money on a substantial cable?

No. You can't even go by size, at least where the insulation is concerned. http://www.roger-russell.com/wire/wire.htm#misleading

[Stub Mandrel]

I used to use leads made up from two-core 13A mains lead (repurposed from a lawnmower). They are all still working 30+ years on!

 

Now I use speakon I'm happy to accept what comes as part of decent quality pre wired leads.

[Baloney Balderdash]

That's what I asked her yesterday: "Does size really matter?"

 

Then she mockingly laughed and walked away, slamming the door to my apartment behind her, and leaving me naked begging on my knees on the floor. 

[Bill Fitzmaurice]

'It's not the size of you pencil that counts, it's how you write your signature.' - John Hancock, 1776.

[BassmanPaul]

I use 12 gauge cable meant for landscape lighting. It's tough, durable and doesn't tangle too easily. Never gives me any problems.

 

As a point I do recommend that all speaker cables, especially those used with higher powered amps, be terminated with Neutrik brand NL4 SpeakOn connectors. The far east versions can and do cause problems. The nL4 connector seems to be the standard installed on all my cabinets.

 

Using 1/4" Phone jacks is not good for an amplifier and simply cannot handle the current requirements of  such amplifiers.

 

Edited May 5 by BassmanPaul

[dclaassen]

On 05/05/2024 at 17:41, BassmanPaul said:

I use 12 gauge cable meant for landscape lighting. It's tough, durable and doesn't tangle too easily. Never gives me any problems.

 

As a point I do recommend that all speaker cables, especially those used with higher powered amps, be terminated with Neutrik brand NL4 SpeakOn connectors. The far east versions can and do cause problems. The nL4 connector seems to be the standard installed on all my cabinets.

 

Using 1/4" Phone jacks is not good for an amplifier and simply cannot handle the current requirements of  such amplifiers.

 

Been using phone jacks for many years, but….since I have a TE head and Genz Benz cabs, how about XLR to speakon?

[Bunion]

1990’s we plugged into back line with what we had, mostly guitar cables 😯,  ohm’s, never heard of them, internet comes along, now I use the correct cable and make sure my valve heads are matched to the correct cab/cabs. 
I never had a bad gig in the 90’s… 

[nilebodgers]

For pro audio we used 4-core 2.5mm2 for almost everything apart from 4-core 4mm2 for ultra-high power subs (e.g. 2kW into 4ohm and similar). (There was also special NL8, EP and socapex cabling that had over 4 cores, although that was all 2.5mm2 too)

 

I’d use 2-core 2.5mm2 for backline bass amps, especially since the interconnect distances are generally very short. 

[Stub Mandrel]

1 hour ago, dclaassen said:

 how about XLR to speakon?

 

Work of the devil!

[Stub Mandrel]

[Phil Starr]

Size matters, but for your speaker cables not a lot.

 

Cable size affects two things, how hot the cable gets and the resistance of the cable. The resistance of a speaker cable only becomes important if you have long runs of cable as you might in a large public address system in a stadium or potentially in a very large PA system at a festival. For an instrument lead of less than a couple of metres you don't need to worry about resistance.

 

Heating depends upon the current flowing through the wire. Supposing you had 400W going through a 4ohm speaker it would be 10Amps (it's the square root of the power divided by the impedance) That's a continuous signal and in music you won't be pushing anything like that continuously and even allowing for your signal being 25% of full power is a long way over what will happen in real life. So a speaker cable only needs to carry 2-3amps and will still have a significant safety margin.

 

A 1mm cable carries around 20A in free air, 1.5mm-25A, 2.5mm-37A and 4mm-50A so even a 1mm cable is overkill for your speaker lead. If ever you look at a speaker coil you can see that the wires are thinner than some people's hair and they carry the current too so the chance of your cable not coping is vanishingly small. If I was running a PA speaker 100m from the amp I'd use thicker cable. The resistance of a 2m long 1mm cable is 0.034ohms so negligable.

[bremen]

God bless Phil and Bill, for sure they are the nemesis of the Audiophool!

[JPJ]

2 minutes ago, bremen said:

God bless Phil and Bill, for sure they are the nemesis of the Audiophool!

Well you say that, but neither rose to the challenge of dispelling the myth around gold plated connectors 🤣

[thebrig]

Thanks for all the advice everyone.

 

Here's what I have done, the cable I've been using for years is a KLOTZ 4mm² 1m cable with Neutrik Speakon connectors, I also had an identical one but was three metres in length which is far too long to connect my head that sits on top of my cabs, so what I have done is cut it down to the size I need, and re-fitted one of the connectors to the blank end.

 

So after reading all the great advice, I now know that a 4mm cable is probably overkill, but at least I know that I have two quality cables that will probably last a lifetime.😉

[Bill Fitzmaurice]

Theoretically current capacity can be a concern, but in the real world that only applies to mains cables. What matters with speakers is resistance. Even with a 6 metre cable keeping the resistance well less than 5% of the load impedance doesn't take a large cable, 18 gauge/1 mm will do with a 4 ohm speaker; the main benefit of going larger is durability. In PA use very long cables don't have as much of a problem with resistance as they do capacitance and inductance, which can cause high frequency losses. For this reason 15 metres is the practical limit for speaker cables. To that end major PA rigs keep the amps close to the speakers. 

[Leonard Smalls]

4 hours ago, JPJ said:

the myth around gold plated connectors

While gold has the advantage of being for all intents and purposes corrosion free any hifi I had tended to live in an area which didn't suffer from either wet or corrosive environments - in which case silver is a far better bet, ohms-wise (that vanishingly small difference in transmissions is like night and day to a proper audiofile )

Saying that, I used to have a pair of 120W Lumley valve monoblocks that weren't so common as to used mere Gold for its terminals... They used Rhodium!

[Bill Fitzmaurice]

With respect to gold and silver, gold has less conductivity than copper, so it's not suited for wire. Any non-tarnishing metal coating of connectors is OK, as it's too thin to offer resistance. Silver has 10% higher conductivity than copper, which means copper need only be 10% larger or 10% shorter to give the same resistance. That makes silver a waste of money.

[Leonard Smalls]

1 hour ago, Bill Fitzmaurice said:

That makes silver a waste of money

Heresy!

 

I've got a pair of very fine Leema Xavier speakers which were modified by Nordost so that all internal wiring is in silver monofilament....

It's a whole new level of performance over the standard, common-or-garden copper-wired ones - inkier blacks, airier highs - it's like the musicians are in the room with you!

 

 

 

BTW, I'm having a minor "giraffe", as yer cockneys say; I worked in BBC sound for many years and even there we couldn't convince one of our dubbing mixers that audio cable couldn't be uni-directional, so I understand the many foibles of hifi-dom. In fact I often peruse the Machina Dynamica catalogue for what self-same cockneys also call a "bubble bath"!

 

Edited May 7 by Leonard Smalls

[BassmanPaul]

19 hours ago, dclaassen said:

Been using phone jacks for many years, but….since I have a TE head and Genz Benz cabs, how about XLR to speakon?

Phone jacks were developed for use in telephone switchboards. They were designed to work with 48V DC at a couple of hundred milliamps. When being plugged into or withdrawn from a socket a momentary short circuit occurs which isn't good for a SS amp. Ampeg used an XLR on the back of its B15 series speaker cabinets. 

 

If your amp has XLR speaker outputs and the cabinet has a SpeakOn then by all means use an XLR.SpeakOn cable.

[dclaassen]

6 minutes ago, BassmanPaul said:

Phone jacks were developed for use in telephone switchboards. They were designed to work with 48V DC at a couple of hundred milliamps. When being plugged into or withdrawn from a socket a momentary short circuit occurs which isn't good for a SS amp. Ampeg used an XLR on the back of its B15 series speaker cabinets. 

 

If your amp has XLR speaker outputs and the cabinet has a SpeakOn then by all means use an XLR.SpeakOn cable.

Ok…then assume I have a male xlr for the output on the TE amp…please walk me through the proper connection for the Speakon.

[BassmanPaul]

Buy the four conductor Speakon as it appears to be a standard across cabinetry manufacturers. Wire the two conductors of the speaker cable to Plus1 and minus1. That's all there is to it.

[dclaassen]

3 minutes ago, BassmanPaul said:

Buy the four conductor Speakon as it appears to be a standard across cabinetry manufacturers. Wire the two conductors of the speaker cable to Plus1 and minus1. That's all there is to it.

The XLR has three leads…