[CactusJack]

I've seen a number of threads about combining two runs of a given speaker wire to effectively create a larger gauge. I couldn't, however, find any discussion about combining two DIFFERENT gauges in series. For example, if I have a 100' run of 12AWG speaker wire and spice on a 3' length of 16AWG at the speaker end, would that completely negate the benefits of the larger 12AWG wire? My non-engineering trained mind thinks that the overall signal loss in this case would be: signal loss in 100' 12ga plus signal loss in 3' 16ga equals total signal loss.

I realize that other factors may enter the equation, such as the quality of the wire splice or difference in impedences. Any comments from you audio experts or engineers would be appreciated.

 

[Bill Fitzmaurice]

My non-engineering trained mind thinks that the overall signal loss in this case would be: signal loss in 100' 12ga plus signal loss in 3' 16ga equals total signal loss.

Correct. In this case the wire would model as 0.31 ohm and 0.02 ohm resistors in series, for a total of 0.33 ohms.

 

[Billy Boden]

Deleted for misreading the OP's question completely.

 

[CactusJack]

Thanks, Bill!

 

[bluewizard]

I think it hinges on whether the wire itself is adequate to start with. In the example given, I would be more worried about 100 feet of 12ga, than 3 feet of 16 ga.

100 ft of 12ga Twin Lead wire is about 0.32 ohms.

However, at that extreme length very likely the inductance of the wire is pretty substantial, and that inductance is going to add additional loss in the higher frequencies. But to know the inductance, we would have to know the specs on that specific wire.

Using a somewhat generic 12ga twin lead wire with 0.19uH/ft of inductance, for 100ft would would have 19µH.

At 4khz you would have an additional loss of ~1 ohms.

At 8khz you would have an additional loss of ~2 ohm.

At 16khz you would have an additional loss of 3.8 ohms for the full 100 feet.

The loss from the 3ft of 16ga is insignificant for either resistance or inductance.

Though we would not assume 100ft on the main front channels, likely if that occurred, it would occur for Side/Rear Surround channels, and the losses would be less noticeable.

Steve/bluewizard

 

[CactusJack]

Thanks for the analysis, bluewizard. The reason I asked the question is that I have a pair of older speakers I want to use as remotes, but their binding posts won't accept wire the size of 12ga. The run isn't actually 100', I was just using that as an example. It's more like 60', which from charts I've seen call for at least 12ga wire. So I thought of running the 60' of 12ga, then splicing on a short length of 16ga, which the binding posts will accept.

 

[Billy Boden]

Thanks for the analysis, bluewizard. The reason I asked the question is that I have a pair of older speakers I want to use as remotes, but their binding posts won't accept wire the size of 12ga. The run isn't actually 100', I was just using that as an example. It's more like 60', which from charts I've seen call for at least 12ga wire. So I thought of running the 60' of 12ga, then splicing on a short length of 16ga, which the binding posts will accept.

You could also use some pin plugs: http://www.monoprice.com/Product?se...4&cadevice=c&gclid=CJb7g9TAocQCFchQ7AodOkUAaQ

 

[Doctor Morbius]

... I have a pair of older speakers I want to use as remotes, but their binding posts won't accept wire the size of 12ga.

Just snip off a few strands until the wire fits. Easy peasy. It won't hurt a thing.

 

[bluewizard]

I think either of those last two suggestions are workable. Though we don't know the details, if the remote speakers will accept banana plugs, that is also an option.

The PIN Plug show, simply trap the speaker wire by clamping down on them. The wire enters from the side. They make the same thing in a Banana plug.

https://sewelldirect.com/Sewell-Ocelot-Banana-Plugs-24k-Gold-Connectors-Open-Screw-Type-6-Pair.asp

Also, snipping away a bit of the wire, a few strands on the end won't hurt anything. It should be fine.


Steve/bluewizard

 

[CactusJack]

Thanks for all the suggestions, guys! The option of splicing two different gauges together is no longer on the table...