It does not. I have a spool of it and like it OK, but in curves it likes to turn on its edge. Not flat to the floor, but not a major trip hazard either. It's fairly flexible. Not as easy to strip the ends as normal wire.
As Scott mentioned early on, many fine strands makes the wire flexible. And ditto a silicon jacket.
@Scottjoplin: I would keep it simple if I were you like Galu suggests. Fussy details won't make much discernible difference, if any, to your listening pleasure. What you are planning will sound good.
As you already have some cable there is no need to buy more. Just stuff it in the trunking. I would probably twist it where it is exposed to stop it splaying and looking a mess. Otherwise why waste cable?
Matching the lengths is sensible if it is practical because of impedance differences. The impedance is a lot more complicated than just resistance so I wouldn't faff about adding resistors. You can safely bundle up the excess provided the + and - wires are wound together so their currents cancel.
I would put care into connectors and soldering them properly. Bad joints are sometimes audible and are avoidable if you have a decent soldering iron. Quality connectors that won't oxidize are recommended. Gold plated? - not really necessary.
You probably won't be able to hear much anyhow since you shorted out your Maplin amp's feedback resistors.
As you already have some cable there is no need to buy more. Just stuff it in the trunking. I would probably twist it where it is exposed to stop it splaying and looking a mess. Otherwise why waste cable?
Matching the lengths is sensible if it is practical because of impedance differences. The impedance is a lot more complicated than just resistance so I wouldn't faff about adding resistors. You can safely bundle up the excess provided the + and - wires are wound together so their currents cancel.
I would put care into connectors and soldering them properly. Bad joints are sometimes audible and are avoidable if you have a decent soldering iron. Quality connectors that won't oxidize are recommended. Gold plated? - not really necessary.
You probably won't be able to hear much anyhow since you shorted out your Maplin amp's feedback resistors.
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That's what I was thinking.I do like it, thanks traderbam, I'll bare it in mind now my plan has changed
@ traderbam. The resistance affects the damping mostly I thought? Though we've established that isn't much of an issue
Re, the Maplin amps they are still working though I've put the feedback back to normal. I'm not using them, the four amps I am using are based on LME49830 with the old Hitachi TO3 lateral mosfets, very "high end"
Re, the Maplin amps they are still working though I've put the feedback back to normal. I'm not using them, the four amps I am using are based on LME49830 with the old Hitachi TO3 lateral mosfets, very "high end"
Coiling a wire pair does not increase inductance. sigh..
Drat! An expert has entered the discussion!
Coiling speaker cable is commonly mentioned as a bad thing to do, but I can see that the magnetic fields of the opposing currents will cancel.
Why is it then, that power cable reels should be fully unwound before use?
Failure to do so can result in overheating at high currents.
A very worthy question.Drat! An expert has entered the discussion!
Coiling speaker cable is commonly mentioned as a bad thing to do, but I can see that the magnetic fields of the opposing currents will cancel.
Why is it then, that power cable reels should be fully unwound before use?
Failure to do so can result in overheating at high currents.
The current carrying ability of an insulated wire is dependent on the insulation. You can buy 60C, 75C, and 90C rated wire, and it's basically the insulation material rating. A 12 awg 90C conductor will have a current rating of 40 amperes while a 60C #12 AWG will be rated 30 amperes. (this from NEC article 310 table 310.17)
Within a multiconductor cable or conductors within a raceway, you have to start derating the wires after three current carrying conductors. Table 310.15(B)(2)(a) shows how to derate based on number of current carrying conductors.
On a wire spool, the actual wire used may have the rated ampacity in free air, but when it is fully spooled, the inner wires will not be able to cool down as they have no air cooling. this is the concept behind the NEC derating of conductors when they go through conduits. If you have a lot of conductors, you have to derate based on numbers, code is explicit.
John
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I'm glad you worked that out, it's very important that cable insulation doesn't melt for a number of reasons...
My speaker cables, which are in reality mains wires, on the other hand are not carrying high current, they are also running loosely in the trunking, not twisted and are of unequal lengths since I decided not to coil them, add resistors or anything anal like that. I can't hear any difference to how they were previously, that could be because I didn't expect or want to. So, all's well that ends well and most importantly they are tidy, out of sight and no longer able to cause me an injury.
My speaker cables, which are in reality mains wires, on the other hand are not carrying high current, they are also running loosely in the trunking, not twisted and are of unequal lengths since I decided not to coil them, add resistors or anything anal like that. I can't hear any difference to how they were previously, that could be because I didn't expect or want to. So, all's well that ends well and most importantly they are tidy, out of sight and no longer able to cause me an injury.
Sommer makes some dandy speaker-level coaxial cable under the Magellan name, with 2x2.5 mm^2, 2x4.0mm^2, and 2x6.0mm^2 equivalent thicknesses. I like coax because it has minimal series inductance, and in RF-noisy environments you have less junk getting back to the feedback loop.
https://shop.sommercable.com/en/Cab...tsprecherkabel-SC-Magellan-SPK-425-0201F.html
https://shop.sommercable.com/en/Cab...utsprecherkabel-SC-Magellan-SPK-440-0201.html
https://shop.sommercable.com/en/Cab...tsprecherkabel-SC-Magellan-SPK-460-0201F.html
Thanks for the latest suggestions. As remarked a little earlier, my requirements regards aesthetics have relaxed somewhat, the only place now where the practicalities are still an issue is where they run across the doorway. At the moment the four separate wires are lying side by side taped to the floor, I'm planning to to cover them with some kind of threshold strip, the thinner the better, if anyone has any suggestions I would be grateful.
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Have you looked at seam binders? You'd have to rout a groove in the bottom for the cables, assuming reasonably sized wires, but once that's done it should be both functional and attractive. Should you decide to move, getting the cable out could be interesting so I'd advise screws instead of glue.
More or less. Threshold strip can cover different heights, say from carpet to tiles, whereas seam binders begin and end at the same height. They seem intended to match two different wooden floors on either side of a doorway, for example.
There are lots types of this, some very rugged. Try an office supply store.
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