A cable question, sort of...

This is gonna sound contradictory to those who don't think about what's going on but what is true of power cords and high voltage/high current speaker cable is quite a bit different than the comparatively low voltage low current going to a sub. In this case being high level doesn't matter because the resistive input on the sub (typically 20k to 50k Ohms) means its not high level after all. As far as the wire and the amp are concerned it is a negligible line level load. Also being a sub means the high frequency range where coiling wire would be most problematic is moot. So still not a good idea but way more theoretical than anything and in the big scheme of things no it is not a problem. And if your question was will it harm the amp or sub then no definitely not.

When you "coil" up the wire, you affectively create a parasitic inductor.  If the cable is long enough that may end up to have too much inductance from the coiling affect, the parasitic inductance may create some resonance which in turn could make the bass of the subwoofer sound a bit mushy.  The question is if your cable is long enough that it will create enough inductance that it will make a difference in listening.  

When you "coil" up the wire, you affectively create a parasitic inductor

No, you don't.  You're not coiling the wire.  You are coiling the cable  (big difference).  Look at the link at my previous post.

In addition increase in reactive impedance, even for the wire,  would be negligible (miliohms) at such low frequencies.

With other words; it doesn’t matter how I "roll up" the sub woofer cable?
Power cables in an eight, sub woofer cables any way that is suitable, likewise ordinary speaker cables?

I would just coil it neatly.  For power cables coiling is beneficial (as many turns as possible).

No, you don’t. You’re not coiling the wire. You are coiling the cable (big difference). Look at the link at my previous post.

It’s just the same. I said "wire" but I could have said "cable". When you coil up either a wire or cable (pick your language preference), you affectively create an inductor - pretty much basic electrical engineering 101 you learn first in school.  The link you posted doesn't say much if anything.

But like I said, if the cable is long enough, you probably see a difference. If the cable is short, then probably not much.

@andy2  there is a big difference between cable and a wire.  Coiled wire inductance is increased because magnetic flux created by each turn adds up.  Cable has two wires that create magnetic flux in opposite direction and coiling them would create something that is called "Common Mode Choke" - a choke that has inductance only for common mode signals and no inductance for normal mode (differential) signals.  This principal is also used in creation of wirewound resistors that have no inductance (bifilar windings).

Coiling will have negative affect on the sound.

if it's the cable that came with the REL, you might want to consider an upgrade cable. I particularly like the upgrade REL and the Analysis Plus, and both come in much shorter lengths than the original REL...

Cable has two wires that create magnetic flux in opposite direction and coiling them would create something that is called "Common Mode Choke"

i think there’s a difference with common choke. In a common choke, the positive and negative have mutual inductance couple between them. When you coil up a cable, there is no mutual coupling like in that of a common choke.

As for the twisted pair, you do increase the mutual coupling, but just coiling up the cable, you just increase the inductance.  

It doesn't matter if you wind it as separate coils or interleave windings - it is still common mode choke.  It will present no inductance for differential signals, since both wires produce canceling magnetic flux.

As I said, common choke works because of mutual inductance coupling between the positive and negative. Coiling up the cable will not increase the mutual inductance since they wire still running in parallel in respect to each other. Not only that, by coiling up, you increase the mutual capacitance of the positive and negative which will degrade the signal dynamic.

If what you said is true then every speaker cables should be all coiling up.

Here's a pic of a common mode choke.  You have to coil it up in such a way to increase the common inductance coupling.  So in order to make a common mode choke, you first have to separate the positive and negative like the picture.  Just coiling up them all together won't make a common mode choke.

https://www.coilws.com/images/common-mode/common-mode-choke_schematics.jpg

I give up.

Kijanki is correct that coiling a cable in which the + and - conductors are twisted together or at least bundled together closely will not increase inductance to any significant degree. But **even if** it did so it still wouldn’t matter because the impedance presented by an inductance is directly proportional to frequency, and under any reasonable circumstances that impedance will be insignificant at the deep bass frequencies that are reproduced by the sub. And **even if** it is not measurably insignificant, it will be totally insignificant relative to the input impedance of the sub’s amplifier, which is very high as Miller indicated, and therefore it still wouldn’t make any difference.

Also, any slight increase in capacitance that may result from coiling won’t matter either at deep bass frequencies, and unless it is extremely high, and the amplifier is extremely sensitive to load capacitance it won’t affect the signals the amp is providing to the main speakers either. And of course the resistance of the cable won’t be affected by coiling.

Regards,
-- Al

Kijanki is correct that coiling a cable in which the + and - conductors are twisted together or at least bundled together closely will not increase inductance to any significant degree.

That’s not what he said that which I was arguing about. The point he made about "common choke" which was the point of contention.

But **even if** it did so it still wouldn’t matter because the impedance presented by an inductance is directly proportional to frequency, and under any reasonable circumstances that impedance will be insignificant at the deep bass frequencies that are reproduced by the sub

Well ... to which degree it will have an affect on the sound is up to the listener. With a good system, the difference could be significant.

 any slight increase in capacitance that may result from coiling won’t matter either at deep bass frequencies ...

Again, it may be insignificant in your system, but it may be very significant in some other system.

Thank you Al.  If we connect speaker with two separate wires apart the inductance of such connection would be proportional to area in between wires.  Bringing wires very close would make this area (and inductance) close to zero.  Twisting speaker wires (it would be stupid not to) reduces inductance even further reducing magnetic flux, that wires produce, to practically zero.  That's why twisting wires not only reduces electromagnetic radiation but also electromagnetic pickup (also capacitive pickup).  Coiling such two wires, even when not twisted creates bifilar coil - a type of common mode choke.  It doesn't matter if it is an air coil or it is on the ferrite core.  Mutual inductance is as high as it gets since two coils (wire and return) are interleaved.

https://www.wikiwand.com/en/Bifilar_coil

I’m probably guilty of trying to reason with people, who don’t want to learn having their mind set on proving that what they know is right. I would advise such, relatively new on our forum, people, that it pays to listen what Almarg says. When you argue with him on technical subjects (I wouldn’t) better check first if you have his education and experience.

When you argue with him on technical subjects (I wouldn’t) better check first if you have his education and experience.

OK, what level of education does he have that nobody should argue with him?

AFAIK Masters in EE in prestigious Columbia University.  What about you?

AFAIK Masters in EE in prestigious Columbia University. What about you?

EE as well.  Just because he has a Master in EE, does not mean he's right all the time.

Thank you, Kijanki.  I usually prefer to let my posts speak for themselves, but since the question has been raised my background is as follows:

BS in Electrical Engineering, Columbia University
MS in Electrical Engineering, Rensselaer Polytechnic Institute
JD (Law Degree), University of Connecticut
Licensed Attorney and Patent Attorney

33 years experience designing and managing design of analog, digital, A/D converter, and D/A converter circuits for defense electronics, primarily airborne radar systems.

Regards,
-- Al

No it doesn't but I have the same degree from less known university plus 40 years experience as a design engineer in electronics (many different fields)  and I can judge about somebody's competence.  The fact that you don't or cannot understand the principle of common mode choke and argue just to argue make me exit.  You don't make friends here.

No it doesn’t but I have the same degree from less known university plus 40 years experience as a design engineer in electronics (many different fields) and I can judge about somebody’s competence. The fact that you don’t or cannot understand the principle of common mode choke and argue just to argue make me exit. You don’t make friends here.

I understand perfectly what a common mode choke is. What you said was over-simplified and that’s the problem.

Whenever I've heard people showing off their degree and experience, there tends to be something else going on.  I on the other hand would never do that unless somebody asked me explicitly. 

I've found a similar thread on another forum with this quote which I found sort of funny.  Some people would go in great length trying to prove coiling does not make any difference.  Notice the words " no appreciable effect", as if there's no effect.

https://www.avforums.com/threads/problems-coiling-speaker-cables.246909/

 I read of an experiment that was carried out where a length of speaker cable was coiled tightly around a 2" diameter steel bar with no appreciable effect on the its performance.

Hi guys.  Nice to see so many people on this forum have varying degrees of higher education.  I do too, but that doesn't matter when it comes to enjoying your hi-fi system.  Nevertheless, I have a new model REL S/812 for about 3 months now.  It's a wonderful product and definitely the best sounding powered subwoofer compared to several others I have owned over the past 30 years.  There are two reasons I don't use the provided REL speaker cable.  1.) It's a rather flimsy, inexpensive, low-grade speaker cable.  2.) It's well below the level of quality cables I have throughout the rest of my system and I just can't feel good about using that.  Personally, my thinking has always been to use the least length of speaker cable possible.  For that matter, the same is true for any other cable (power or signal).  Speaker cables, however, are probably the most important cable to keep as short as possible.  

Simna, once finalizing the best location for your REL subwoofer you can either 1.) cut the supplied speaker cable to your required length, 2.) purchase the REL upgrade speaker cable ($500 at retail price) and cut it to your required length, or 3.) purchase another brand speaker cable, made to work with REL, and order it at the required length.  Add about 1 foot to your required length so in the event you need to move the woofer around a bit, for sound improvement if other variables change such as new furnishings, you will have some excess to work with.  What I did was purchase Audioquest Rocket 88 speaker cable that is terminated with the Neutrix Speakon connector.  Audioquest makes this to order, that is, to your specified length.  They also use an upgraded part from Neutrix that is a far superior version of the Speakon connector that REL supplies.  They will make the REL cable with options of either the Rocket 22, 44, or 88.  The Rocket 88 also includes the DBS device so I made that my preferred choice.  It's expensive but I only needed 9 feet.  Any authorized Qudioquest dealer can place that order for you.  My local dealer was very helpful, Audioquest was very quick, and I received the order in about 1 week.  I feel very satisfied and have zero worries about any of the topics discussed above.  I hope this helps you.

Answer this:

A brand new pair of shoes need some breaking-in and that most people would agree. But for some reason, a cable needs breaking-in seems somewhat mysterious. Shoes and cables are made of the exact same materials: electrons, neutrons, protons ...

Also, think about this. The force your feet exert on the shoes is the same force the move electrons. It’s called electric field. When you press on the shoes, it’s your electric field that pushes on the shoes. The whole time you’re wearing your shoes, none of skin of your feet literally never comes into contact with the shoes atoms.

The same electric field that pushes the electrons in the cables that creates a current.

I would also reccomend upgrading the standard rel connector cable.

 I used to own the rel  baseline blue which was a significant upgrade , I sold it on as my amp supplier reccomended using rca/balanced connection.

I suspect that  solid core connectors made most of the improvements and you could get an aftermarket one that was very cost effective.

So you have to resort of AI cheap shot lols.

heaudio123 They don’t have to be separated, but they often are because it is easier to wire, for isolation, and to reduce capacitance between coils. Common mode air choke has to be wired with a pair of wires (interleaved) because of leakage flux. Such coil is called bifilar coil and is used to wind non-inductive resistors. Look at the first picture on the top of this link: https://en.wikipedia.org/wiki/Bifilar_coil
It doesn’t matter that right side is shorted - you can cut it and connect speaker there. It will still work exactly the same, since opposing currents are identical. Wikipedia description "Bifilar coils impose an inductance in the common mode, but impose no inductance in the differential mode" is basically definition of common mode choke.

I’m not an electrician, but I played one on TV!  Sheesh guys. @kijanki is correct. There is a difference between one wire coiled and two wires coiled.  Speaker wire can also be called speaker cable.

But as @millercarbon said early on, with low frequencies, it’s no big deal either way.

OP, you are just fine coiling the wire up.

JD