Wire question

[Coytee]

I'm one that's happy using 12-g wire from HD. I was recently given some 'fancy' wire. This wire appears to be two stranded 10-g wires (I think they're fully stranded but if not then it's a solid core with strands around it) This stuff looks about the size that I have going to my stove/oven!

Anyway, it appears to be two 10-g wires, individually insulated of course. What I find interesting is SURROUNDING this pair of wires is one of those braided wire sheaths. There is then the plastic wrap surrounding the whole ensemble.

The guy who gave it to me, as I recall, suggested to me that the two wires will go from amp to driver leads. He then said that the ground sheath would be terminated on the amplifier end but OPEN on the speaker end. He said this sheath will help minimize any noise pickup and if I did get something, it would drain it to the ground on the amp instead of carrying it towards the speaker.

1. I don't know if I remember exactly what he said correctly so if I butchered some of the above, my pardons

2. I don't know if any of the above is accurate, regardless of what he told me.

3, How might I best try to utilize this wire? As it is right now, I'm thinking in putting it from my Mc-2102 to my K-402's. (or might it be more interesting to put it to the bass bins since they are exposed to more power).

4. Regardless of where I might use it, should I use it as a simple 2 wire and buy some termination spades so I can somehow plug it in or am I just as well trimming some of the excess girth and use the smaller tip as a direct connection to my amp/drivers?

5. What about that ground wire sheath? This is the part that for me, is something out of the ordinary. Should I forget about it? Try to terminate it somehow? (if so, where) I do not recall that ANY of my amps have ANY kind of a ground to them but I might be in error there. If they do not have a ground (I just verified the solid state on the bass unit doesn't) then is this sheath useless to me?

6. If there IS perhaps a ground on the McIntosh amp (dictating that I use it on the K402) would I do as said and simply ground one end of it? What might this sheath do for me, if anything?

He gave it to me as a gift to try and I told him I'd try it & see what happens. I'm perfectly willing to give it a whirl. I don't expect much (if any) difference than the 12-g stuff I'm using already but I'll try to keep an open mind. Besides, since XLR cables have the sheath around them, maybe there's more going on than I'm aware of?

What say you?

[TNRabbit]

When's the last time you picked up interference of any kind from your speaker wires.....?

I don't buy it. Of course, the best way to know is to do a side-by-side comparison....

[Coytee]

I did some rewiring (both speaker wire AND IC's) and picked up some hum. It was that comment to him that made him decide to send these to me. He suggested that the grounding sheath around the wires would help elimnate that (probably 60 hz) hum.

[mas]

This is simply the speaker version of 'directional cable" (as distinct from 'directional wire' where the electrons supposedly flow more easily in one direction - and I don't know of anyone using "strained" wire!)- a configuration very common and valid used with component interconnects where the shield is left floating on the component end opposite the pre-amp in order to provide an effective shield while avoiding ground loops.

This concept is equally valid for speaker wires. The ground would be referenced to the amplifier in this case (and floated at the speaker end) and it will offer enhanced rejection of RF/EMI interference. Most likely you would have to ground the 'shield to the chassis - something not easily done on all amplifiers.

Some ask "Is it necessary?" Are you experiencing problems with induced signal ingress? I guess its rather like asking if you need a flu shot. Do you anticipate a reasonable chance of catching the flu? If so, then it is probably a reasonable precaution.

[Guest " "]

"He then said that the ground sheath would be terminated on the amplifier end but OPEN on the speaker end. " 

This is normally done with internconnects to prevent ground loops......ground loops would be difficult in normal speakers but possible with active sub-woofers.

[Klytus]

My first inclination is to agree with you. I don't expect that you will hear much of difference. How much noise can be injected through the output of your amplifier? There is probably a better benefit in just making tight mechical connections with your existing wiring. B&W recommends that the resitance in your wiring be no more the 300 milliohms. That includes how the wiring is secured to your amp and speakers combined regardless of the run length.

Do you have a 4 lead milliohm meter?

[InVeNtOr]

i can tell you working on aircraft we do this. the twisted pair of wires, with no sheild, alone will prevent some emi. the twisted pair with the sheild prevents most emi. now according to the engineers i work with, you can float one end and ground the other and it will work just fine. also in most cases you just float both ends and it should also work as well. in the aircraft we have hundreds of these pairs of wires running mostly over 100' all tied together. we normally ground both ends, but there is a few applications that we just ground one end.

sounds a little gibberish...

basically you don't HAVE to ground an end. you CAN ground one end and you will be okay. if you can ground both ends it may work better. the only thing to remember keep as much of the sheild as possible. only strip back no more than 3" on each end. also trim the sheild so there are no stray strands and if you have it, put heat shrink over the cut strands so it makes it a clean termination. (basically covering up the sheith that is cut back).

[russ69]

Coyote,

Speaker wires do have a sonic effect. I prefer solid core designs over stranded. Try a pair of Audio Quest Type 4 for a nice bump in dynamics. Go for some silver if you want a hotter top end. You don't have to spend a bundle on cables but the right ones are really worth the money. Try some different kinds, I'll know you'll like some, and zip cord will be history.

Thanx, Russ

[meagain]

Coytee - How do they sound?

[Erik Mandaville]

"Most likely you would have to ground the 'shield to the chassis - something not easily done on all amplifiers. "

Although easily done on many amps where the 'common' speaker output connection is referenced to the chassis ground.

Erik

[Erik Mandaville]

"also in most cases you just float both ends and it should also work as well. "

How so?

Erik

[Erik Mandaville]

The point being that with a twisted pair, providing that one of the conductors is grounded, the shield really isn't doing anything if it isn't grounded. Not all twisted pair shielded cable connections, if used between input to first stage or output stage to feedback loop, consist of one hot and one ground. Sometimes, both conductors of the twisted pair are used for signal only, and both in turn are shielded by the twisted braid (or other shield device) that's grounded at either one or both ends. The twisted pair (one of the two providing the ground return) is the important element. If, in the case of not knowing any better, one decides to remove the shield at both ends on a standard coax IC, one will run into a bigger problem than a little influx of RFI/EMI. Not all interconnects are twinaxial.

Erik

[PrestonTom]

"Most likely you would have to ground the 'shield to the chassis - something not easily done on all amplifiers. "

Although easily done on many amps where the 'common' speaker output connection is referenced to the chassis ground.

Erik

Certainly, this is the usual case; however, some amps will not have a common ground between the two channels. Car amps would be one example.

As far as the original question goes, it is probably not necessary. A cable run with a high impedance signal is susceptible to picking up noise (source to pre-amp or preamp to amp or a mic or phono cable). However the amp to speaker conection is low impdedance and would not be very likely to pick up any noise. However, I think you already knew this and are being overly cautious.

Good Luck,

-Tom

[Erik Mandaville]

And the usual case is what prompted my response. I've never had a situation where a speaker cable required shielding, but some cases may be different. A simple continuity check between output common and ground (chassis) is not too hard do.

Erik

[Coytee]

Not ignoring the thread...been out of town couple days and just now peeked in.

Wire is in my car so I've done nothing with it and probably won't for at least a week or so.

[wrench_peddler]

Years ago I lived next door to a guy who worked on CB radios in his garage. My bedroom was about 40' from said garage. He would often awaken me by talking on his radio and I would hear him on my speakers, loud and clear. My stereo was NOT on. A braided shield would have probably stopped that problem. If you need a place to ground the shield at the amp, you should be able to loosen a screw on the cover of the amp and slip a wire connector under the screw and tighten it back down. You may want to do this on the back or the bottom of the amp because you will really need to scrape the paint off the area under the screw so you actually have a good metal to metal ground.

[pzannucci]

What I have seen is that if I run my speaker wire next to either my line conditioner or my isolation transformer (even within about 18 inches, I will pick up hum.

I don't know if the grounded shield would fix this but it might be worth trying