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[Michael Mills]

Is it worth the expense and to go with 4 conductor cables to each sub box, example...jbl 828s in discrete vs a 2 wire in parallel?
How does it relate to damping,  ie. Each speaker in each box cabled back independently via (4 wire) only to have both pair terminate on the same output of the amp to achieve a 4 ohm load

[Brian Jojade]

Is it worth the expense and to go with 4 conductor cables to each sub box, example...jbl 828s in discrete vs a 2 wire in parallel?
How does it relate to damping,  ie. Each speaker in each bow cabled back independently via (4 wire) only to have both pair terminate on the same output of the amp to achieve a 4 ohm load

If you have 4 conductors vs 2 and they are all the same gauge, more conductors would mean more copper and thus less loss in the line.  In real world scenarios, unless you're running undersized wire or very long distances, you're going to be hard pressed to end up with an audible difference.

[Steve-White]

If you have 4 conductors vs 2 and they are all the same gauge, more conductors would mean more copper and thus less loss in the line.  In real world scenarios, unless you're running undersized wire or very long distances, you're going to be hard pressed to end up with an audible difference.

+1

In practical application, it doesn't matter.  If making 100' runs from the amp, then it's worth consideration.

[Nathan Riddle]

Michael,

You may enjoy this calculator for determining all of the various variables.
https://products.electrovoice.com/na/en/cableloss

And a paper on damping factor:
https://linea-research.co.uk/wp-content/uploads/LR%20Download%20Assets/Tech%20Docs/Damping%20factor%20debunked%20-01a.pdf

GLHF!

In practical application, it doesn't matter.  If making 100" runs from the amp, then it's worth consideration.

I think you mean 100ft 

[Michael Mills]

If you have 4 conductors vs 2 and they are all the same gauge, more conductors would mean more copper and thus less loss in the line.  In real world scenarios, unless you're running undersized wire or very long distances, you're going to be hard pressed to end up with an audible difference.

Yes all conductors are same size, 11/4 cable with NL4 on box end and 1 binding post with both pair on amp side. Amps are Crown MA 2500 bridged, with 1 amp per box. Cables are 50'
4 sub boxes and 4 amps.

[Caleb Dueck]

Amps are Crown MA 2500 bridged, with 1 amp per box. Cables are 50'
4 sub boxes and 4 amps.

The main benefit to using 4 conductor cable, besides higher damping factor, is that you can use one amp channel per driver rather than one per sub.  Especially if it's a 4 ohm sub (dual 8 ohm drivers), each amp channel will run at 8 ohms rather than 2 ohms.  Even though the power to the sub looks lower on paper, look at amp output vs time graphs, as that along with higher damping will help it perform better overall. 

I'd say go for it, as long as it addresses the amps as well.

[Steve-White]

I'd be inclined to look at the numbers for 4x 14ga - not so sure you want to bridge those amps into a 4 ohm load.  With one amp per pair of 18's I'd go dual channel to the drivers with independent runs to them from the amps.

[Matt Vivlamore]

Is it worth the expense and to go with 4 conductor cables to each sub box, example...jbl 828s in discrete vs a 2 wire in parallel?

The switch on the back of the SRX828S, isn't the same as the old SRX47## series.  The switch allows you change from Pins 1 to Pins 2.

What can do is run NL4-4C into the 828 (switched to Pins2) and then Link up to your mains with jumper (Pins1).  I did this when I had my SRX7## system and it worked out great.

[Caleb Dueck]

The switch on the back of the SRX828S, isn't the same as the old SRX47## series.  The switch allows you change from Pins 1 to Pins 2.

What can do is run NL4-4C into the 828 (switched to Pins2) and then Link up to your mains with jumper (Pins1).  I did this when I had my SRX7## system and it worked out great.

It's a simple internal rewire to have pins 1 to one driver and pins 2 to the other. 

[Tim Weaver]

I'd be inclined to look at the numbers for 4x 14ga - not so sure you want to bridge those amps into a 4 ohm load.  With one amp per pair of 18's I'd go dual channel to the drivers with independent runs to them from the amps.

This.

We have been running 4 conductors on subs for years so that each driver gets powered discretely. The benefit gets better when you have multiple dual 18's and you never know how many you are going to use that day. If you out out 3/side with the standard wiring you'll have a 2 ohm load and a 4 ohm load, but with the discrete wiring both loads would be 2.6 ohm. You'll get a balanced load on your amp (and distro, depending how its wired) by using the discrete wiring.

[Tim McCulloch]

This.

We have been running 4 conductors on subs for years so that each driver gets powered discretely. The benefit gets better when you have multiple dual 18's and you never know how many you are going to use that day. If you out out 3/side with the standard wiring you'll have a 2 ohm load and a 4 ohm load, but with the discrete wiring both loads would be 2.6 ohm. You'll get a balanced load on your amp (and distro, depending how its wired) by using the discrete wiring.

You also double the damping factor by halving the cable resistance and doubling the load impedance by driving the subs as "8" Ohm loads instead of "4" Ohm loads.

[Jared Bartimus]

This.

We have been running 4 conductors on subs for years so that each driver gets powered discretely. The benefit gets better when you have multiple dual 18's and you never know how many you are going to use that day. If you out out 3/side with the standard wiring you'll have a 2 ohm load and a 4 ohm load, but with the discrete wiring both loads would be 2.6 ohm. You'll get a balanced load on your amp (and distro, depending how its wired) by using the discrete wiring.

Are there any risks if only one driver gets disconnected/has amp problems?

[Tim Weaver]

Are there any risks if only one driver gets disconnected/has amp problems?

Yes and no.

The amp doesn't care. But if you are really abusing your subs you might blow the one that is connected because it is both trying to make noise AND flopping the unconnected one around in the cabinet which sucks power and volume. If you keep pushing it, you'll fry the voice coil or just rip a cone.

[Mike Caldwell]

Yes and no.

The amp doesn't care. But if you are really abusing your subs you might blow the one that is connected because it is both trying to make noise AND flopping the unconnected one around in the cabinet which sucks power and volume. If you keep pushing it, you'll fry the voice coil or just rip a cone.

No real difference than in a dual woofer sub with parallel wired drivers and if one blows.
Some subs are dual chamber so it would not unload if one driver blows.

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