biwire trick


Some of you seasoned vets may have heard of this, but I had never thought about it. Researching jumpers led me to Music direct's website, where in the description of some Nordost jumpers it read to try switching one lead from both mid and tweet. IOW take the positive lead from the tweeter and swap it with the pos lead from the mid.

I have a true biwire setup (separate runs for mid and tweet), don't know if this makes a diff, but the sound definitely improved: fuller, more natural, larger stage. try it as one of the easiest, free tweaks to do. You may be surprised.
tholt
If the wires are the same type and close to the same length and are all grounded together at the binding post on the amplifier end then this cannot possibly make any difference at all - unless you fixed a poor contact when making the change or unless you concentrated harder than usual trying to discern a change (in which case most people do hear a change or think they do - due to the placebo effect)
Just about everytime some kind of change is made, you always read this comment :

but the sound definitely improved: fuller, more natural, larger stage

And agree with Shadorne's comment :

or unless you concentrated harder than usual trying to discern a change (in which case most people do hear a change or think they do - due to the placebo effect)
Shadorne and Riley804, I'm not so sure.

Keep in mind that the swap Tholt is describing will result in different frequency components flowing in the + leg and the - leg of each two-conductor pair of wires. It seems to me that would in effect amount to a change in the inductance of the cables, because the magnetic fields associated with current flow through adjacent conductors would no longer be equal and opposite.

As you probably realize, depending on cable length, cable type, and the impedance of the speaker at high frequencies, speaker cable inductance can sometimes have a significant effect on upper treble response. And upper treble response would seem to be something that can subjectively correlate with soundstaging.

The connection swap would also reduce the degree to which any noise pickup that may occur is common mode. I would not expect that to generally be significant in an amplifier-to-speaker connection, because of the low impedances and relatively high signal levels that are involved, but I would be hesitant to totally rule out the possibility.

As you know, I am certainly one who tends to be skeptical about a lot of tweaks that are reported, but in this case I would not rule out the possibility that the differences were real.

Best regards,
-- Al
Al,

I think the spacing between the wires would need to be significant to be audible. If the wires were 1 meter apart (huge) then I calculate a roll off at 20 Khz of 0.25 dB into an 8 Ohm load (most tweeters) compared to the signal level at 200 Hz. This is peanuts and barely at the threshold of audibility.

Fortunately, someone has already worked it out for any configuration and the details are here

If the biwires are in the same jacket or are laid out within an inch of each other (most likely scenario) then my original statement stands.

However, not knowing what crazy setups people might dream up and use, I guess I stand corrected.
I vote Dcrugby's post as Post Of The Day.

Almarg, I can no longer count the times I have learned something new from your posts.

Audiogon moderators,
Would you consider a 'Post of the Day' button/link one could push next to each post?
I love all you pessimistic audiophiles out there. For us, it's "prove it."

The reason I tried it is as follows from the aforementioned description of the Nordost jumpers on MD:

"Diagonal Bi-Wire
For those looking for maximum performance from their bi-wire speakers, Nordost has a recommendation. Connect your speaker wire to the speaker as follows: Red lead to the Red midrange/bass post, Black lead to the Black tweeter post. Then insert the Norse Jumpers as you normally would, sit back and hold on to your socks. The effect is astounding, with greater focus, detail and less haze and grain. We don't really understand how it works, but it does so try it for yourself!"

This theoretically could make sense. I translated it to evening the load between cables, though perhaps Almarg has more properly defined it. I really shouldn't have described it as a tweak or trick, since I really don't believe it is one. It's switching the leads.

3 things can happen: it sounds worse, it sounds the same, it sounds better. You be the judge on how neutral your analysis is. Don't think about why it should or shouldn't work. It wasn't very hard for me to hear a difference. Make sure to turn off the amps first.

01-02-11: T_bone
I vote Dcrugby's post as Post Of The Day.

Almarg, I can no longer count the times I have learned something new from your posts.

Audiogon moderators,
Would you consider a 'Post of the Day' button/link one could push next to each post?
T_bone (System | Threads | Answers | This Thread)

Almarged! Almarg, thank you for your insight and wisdom, always.
I must be a little sow today as I can't seem to wrap my head around this hook up scheme. Someone please try to straighten me out. If I am getting this right, this would leave the negative mid/bass post with no connector attached to it at all. Is this correct?
Thanks very much for the nice words, gentlemen.

Rcrerar, no, what Tholt is describing is a conventional biwire arrangement but with the + conductors of the two cables interchanged at the speaker terminals. It may not have been clear to you that the statement he quoted from the MD site is addressing something different, a non-biwire arrangement in which jumpers are used but the connections of the + and - conductors of the single speaker cable are made to "diagonal" speaker terminals, rather than adjacent speaker terminals. I have no idea, btw, why the latter would make a difference sonically, although a number of people have claimed in past threads that it did for them.

Shadorne, neat calculator that you linked to. I agree that if the two sets of cables are within the same jacket, the effects I described would probably be reduced to insignificance. However, if they are physically separated by some number of inches or feet over a significant fraction of their run length, I think that the following factors would make those effects more significant than the calculator would seem to indicate:

1)The calculator assumes the speaker is purely resistive. Dynamic speakers will tend to have an impedance at high frequencies that is somewhat inductive, due to tweeter voicecoil inductance. Cable inductance will have a greater effect on bandwidth when it is connected to an inductive impedance than when it is connected to a resistive impedance of the same magnitude.

2)The speaker impedance at high frequencies may be less than the 8 ohms that is assumed in the calculator.

3)While the effect may amount to only a db or less at 20kHz, which I agree is insignificant in terms of steady-state frequency response, as you certainly know our hearing mechanisms give increased emphasis to the leading edges of rapidly changing transients. Fast leading edges, of course, correspond to high frequency spectral components.

The bottom line is that I'm not asserting that the effects I've described are necessarily the explanation of what Tholt perceived, but that there is technical rationale that is sufficiently plausible for this tweak to not be dismissed as placebo effect.

Best regards,
-- Al
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Al,

The majority of tweeters are above 6 to 8 Ohms in the 10 KHz to 20 Khz range - rising with frequency due to the inductance. So the applet formula in the link is a pretty good approximation for the 10 KHz to 20 KHz range.

I think we can all agree that below 10 KHz we can pretty much ignore the effects of cable inductance.

In the applet I used 5 meters of speaker cable with + and - leads separated by 1 meter in order to get a 0.25 dB drop at 20 KHz compared to 200 Hz. I deliberately used an "extreme example" to show that the effect is very small in all situations.

However, the effect does exist and you are absolutely right that it might be audible in some situations. I stand corrected.

I would argue that this "trick" is definitely the wrong way to bi-wire speakers - at the very least it goes against normal way to make electrical connections which is in general to use either two wires side by side in close proximity for low frequencies (audio) or a coaxial cable for ultra HF applications.
Yes, the MD description I used/quoted is not the same as what I'm describing (single cable + jumper arrangement), but it led me to think of what I've described here. I stand by my first statement -- I hear more air, more dimensionality, larger staging, more natural and full sound. Unless there is a downside electrically, which I haven't read yet (Almarg...assuming you would have brought it up?) I'm hearing positive differences and don't have a good reason to revert back to the conventional hook up method.
Unless there is a downside electrically, which I haven't read yet ....
I think that the only conceivable downside would be a philosophical one, along the lines of Shadorne's last comment. It could be argued that you are raising the effective cable inductance to compensate for an imperfection elsewhere in the system or the room. But given that nothing is perfect, and that the adjustment is extremely small in electrical terms, as a practical matter I don't see any issues. I would think of it simply as fine tuning the system.

Best regards,
-- Al
I would argue that this "trick" is definitely the wrong way to bi-wire speakers

Wrong? Different.
Wrong? Different.

No just plain wrong. If one wanted to roll off the treble ever so slightly then there are better tools for that, such as tone controls, an EQ or more room treatments etc.

Cables should be neutral. Using cables to tune things is such a cumbersome way to achieve a simple task it beggars belief!
No just plain wrong. If one wanted to roll off the treble ever so slightly then there are better tools for that, such as tone controls, an EQ or more room treatments etc.

Who said anything about tone control or rolled off treble? Please re-read my my findings. But I suppose I could go back to the 'right' configuration, satisfied that I'm not doing something I'm not supposed to be doing, and just pretend that it sounded better than the 'wrong' way.

Scream 'cables should be (insert word here)!' all you want, Shardorne. As Elizabeth said, "Theory is great for arguing." I'm not here to argue.
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Good for you for experimenting and trusting your ears.

As long as nothing blows up, or now has a reason to, why not (thanks Al)? I was piqued by the Nordost write up -- to attach the leads to treble and mid from a single cable. In their case they fill the gap with their jumpers, but it seemed like they were essentially balancing the current load. Biwire, in principal, should do an even better job since it would be truly balanced.

No idea. I wouldn't have posted it if it didn't make a difference. Even Nordost doesn't know why it works. IOW, theory can kiss my axx.

Oh, and always, YMMV
I run 2 completely separate cables per speaker for the highs and mids (total of 4 runs of cable for L+R). I thought running the highs and mids in separate cables was part of the benefit of biwiring. Of course the two runs are connected at the amp end anyways. Would a diagonal biwiring approach make sense in my situation?
Tvad is absolutely right about education - knowledge certainly does instill principles about the right way and wrong way to hook up electronic equipment.

All I am saying is that from a "best practice" perspective it is wrong to use speakers wires with a large + and - wire separation to create excessive induction in a part of the system circuitry that is supposed to be as transparent and loss-less as possible.

Of course you are all free to do whatever you want. If an odd way to hook things up happens to work and you like to do it then great - it is not wrong from your individual perspective with your system as it just happens to sound better.

However, on the whole across all the many systems world wide, your approach is not best practice and I would not recommend it (and that is what I was trying to say). The global standard of selling speaker cables in jackets with two closely adjacent + and - wires is still the current best practice and the "right" approach to get the equipment to perform according to the manufacturer's intent.

I know Al will agree with me on this one, as he is a EE and all audio equipment is designed to be hooked up with connections that are as transparent as possible.
It's worked for me.

I have DIY speaker cables and name brand speaker wires.

I have Ref 3A biwired speakers(which come with solid core thin wire jumpers).

I've posted here previously asking about what speaker wires other Ref owners were using, because I had not been having much luck whether I biwired or ran with jumpers using some pretty decent name wires.

Then I saw the Nordost ad and decided "why not" about the only thing i haven't tried.

It worked.

Even better than two runs of my DIY speaker cables.
The single run of speaker wires in the diagonal arrangement with the stock Ref 3a solid core jumpers has given me a much clearer listening experience.
It seems to flesh out the top end with no loss of heft to the low range.
I always felt running the conventional single wire with jumpers was a compromise depending on which set of speaker terminals you designated as the primary pair for the wires.

There is no sense of loss in either the top or bottom in this configuration and I'll leave the why for others to contemplate.

The upside is that one decent set of single speaker wires is all I need now, which is a cost effective improvement if I decide to upgrade my DIY wires.
What if you have a triwire setup with the midrange and bass jumpered together for Definitive Technology Bp 2002 auto power on reasons in order to keep the bass operating? The tweeter is separate. Any recomendations?
I tried this myself to see what the results would be. My connections are a bit different, but electrically the same. I am using a Parasound HCA 3500 for the amplifier. This amp has two sets of binding posts per channel so if you want to do true bi-wire you just hook up twice as many cables. In my case I tried this in the "standard" true bi-wire configuration. As expected the soundstage got bigger, the highs were more noticeable and airy etc etc. What came along with this change though was a noticeable reduction in bass...the drivers in the speaker seemed almost out of balance. I then tried taking the following: midbass + to midbass + midbass - to tweeter -, tweeter + to tweeter + and tweeter - to midbass - . This arrangement brought the bass back to the speaker immediately. There is now improved clarity, but without the sacrifice of bass reduction. This experiment was done on Joseph Audio RM7xl's which come with the standard gold plated brass jumpers. I am now runnining Kimber 8tc (white and clear) in true bi-wire set up with the diagonal or cross swapping of the negative leads. Because my amplifier already essentially has jumpers built into it with the two sets of binding posts per channel, there is no need for a speaker jumper as described in Nordost's suggestion.