Biwire Options

[rollo]

   There is a buzz on about how to best wire bi-wire speakers. Hooked up the Snell EIV conventionally with positive lead from amp to positive lead of bass connection and the bass neg using jumpers from positive to positive and neg to neg to tweeter.
   OK sounded just fine. As per Audioquest recco I wired the positive from the amp to the positive tweeter connection and the neg. from the amp to the neg. bass connection. Then using jumpers connected positive to positive of tweeter and bass and then neg from bass to tweeter.
confused yet 
   This is a HUGE improvement. Huge. greater clarity, veils removed, opened up sound stage and better defined bass.
    In my forty plus years how did this method allude me. A no brain-er try it.  BTW also worked wonders with an all Lamm and Analysis system. Huge I say.

charles





   
   

[mdconnelly]

I've heard of this trick before.  I don't hear the HUGE but it does seem to make a difference.  Now if someone could just lend an ounce of credibility and science to why it would make any difference, I'd love to hear it. 

[tmazz]

Correct me if I'm wrong, but it does not sound like you are bi-wiring. Bi-wiring would be the running of separate cables from the amp to the bass and tweeter terminals on the speakers.

What you are doing is using jumpers to connect a bi-wire equipped speaker using a single run of cable. I have never owned a pair of bi-wire speakers, but I do remember Steve at AudioVisions saying that there was a huge difference on the Vandersteen 2Cs between jumpering a single wire and truly bi-wiring using two runs of cable for each speaker. You should give it a try.

[richidoo]

ecramer 1st mentioned it here on audionervosa, many moons ago... Can't find his post tho  

I don't know why it works, but I have plumbing-like imaginations which don't comport with physics. Wrapping the amp around the whole crossover, instead of just one end.

I think that the better the jumper wires and their connections, the less audible will be this trick. It allows more direct connections of the amp to the crossover circuits, so better damping, etc. When i do it, I imagine hearing that wherever the positive amp lead goes plays a little stronger.

You can also try the opposite too. Just leave the jumpers in place and then switch the speaker cables to all bass, all treble, only + on bass, or only + on treble. Each sounds different... cuz zynergy.

[tmazz]

If you run the jumpers from the + to the + and the - to the _ terminal the amp is seeing the two loads in parallel whereas if you change the jumper and the speaker cable to that the both go from a + to a - then the two loads are in series will make a huge difference in the impedance the amp is looking at.

Bi-wire speakers are designed to have a separate run of cable to each terminal that come together at the amp output, I would think that the speced impedance of the speakers assumed a parallel connection. For example if the total impedance seen by the amp is to be 8 ohms and the HF and LF sections of the speaker have equal impedance then each of the sections would have to be 16 ohms. So if you switch the jumper wiring so that the two sections are in series then the amp would be looking at a 32 ohm load, 4x greater than what it was before. This could explain the difference in sound that you are hearing , especially if you are using a tube amp and don't (or can't) change the output taps accordingly.

Also keep in mind that a 32 ohm load is generally outside of the design specs of most equipment sold for use in the home.

Not saying that wiring the speakers that way is wrong, I don't think wiring to a higher impedance load can damage an amp the way an impedance drop can, just thinking out loud as to the reason why you hear a difference.

[Werd]

  There is a buzz on about how to best wire bi-wire speakers. Hooked up the Snell EIV conventionally with positive lead from amp to positive lead of bass connection and the bass neg using jumpers from positive to positive and neg to neg to tweeter.
   OK sounded just fine. As per Audioquest recco I wired the positive from the amp to the positive tweeter connection and the neg. from the amp to the neg. bass connection. Then using jumpers connected positive to positive of tweeter and bass and then neg from bass to tweeter.
confused yet  
   This is a HUGE improvement. Huge. greater clarity, veils removed, opened up sound stage and better defined bass.
    In my forty plus years how did this method allude me. A no brain-er try it.  BTW also worked wonders with an all Lamm and Analysis system. Huge I say.

charles





    
  

That is how I ran my warfedales in non bi wire.  

As it turns out. Bi wiring isn't recommended over single run since it increases impedance into the bass terminals since you effectively split the cable in half using the same gauge. The best way and most expensive is to run multiple strands of the same low gauge into your bass terminals and jump into the mid tweeter terminals. Here you have decreased the working impedance into the drivers terminals that have  the most control output from amp. Like dampening and speaker break up on the bass drivers (distortion).

[rollo]

  It appears that back EMF from the woofer is decreased or almost eliminated when diagonally connecting.
   We tried two sets of cables as oppossed to single run and jumpers as well as single pair with diagonal jumping. To our ears the diagonal won out.
   


charles

[Werd]

That is how I ran mine. Did you try multiple runs same gauge using diagonal and also into bass low freq terminals?

[richidoo]

  It appears that back EMF from the woofer is decreased or almost eliminated when diagonally connecting.

It may be microscopically affected by changing speaker post connections, but only to the degree that the connection resistances change to the various generators of EMF in the speaker.

By moving the cables you are either adding or reducing temporary connections in the signal path, which affects damping.

If the cables were formerly connected to bass terminals that is the least resistance connection to the largest generator of EMF in the speaker, so the amp sees the highest possible EMF. Now if you move the negative cable to the tweeter, the circuit is still the same, but you have reduced the amps connection impedance to the tweeter, and you have increase the impedance to the woofer by moving the resistor (the temporary connection speaker post) from the tweeter circuit to the woofer circuit. The tweeter's damping (detail) increases, and the woofer's damping (slam) is worse. But this also means the woofer's ability to preturb the amplfier with backEMF is also reduced slightly, but not by much, because you still  have a voltage source amplifier with a low output impedance that conducts the VC-generated current, and you still have lowish impedance connections from VC to amp. Nothing has changed very much technically, which is why this tweak is a secret, but small changes are audible.

To eliminate backEMF completely, you need a current source amplifier, which has infinite output impedance, showing an open circuit to the VC, so no EMF current can flow. Like First Watt F4, but this kind of amp has special needs and won't work with normal speakers.

[BobM]

You might try swapping them and see what happens. So 2 configurations

(1) + to tweeter - to bass
(2) + to bass - to tweeter

One way should be better overall. You are likely improving the transient response of the amp along the cable to the tweeter one way more then the other, since the tweeter delivers most of the sound to your ears. That is the essence of true biwiring anyway, reducing the impact/effect of the load from the bass signal/driver on the tweeter's signal.

I know I am not explaining this correctly, or not totally clearly. But you are effectively trying to do the same thing as true biwiring - improving the signal to the tweeter.

[tmazz]

 It appears that back EMF from the woofer is decreased or almost eliminated when diagonally connecting.
   We tried two sets of cables as oppossed to single run and jumpers as well as single pair with diagonal jumping. To our ears the diagonal won out.
    


charles

We can theorize all we want in these discussions, but in the end the only thing that matters is what the ears think.  (well maybe that and we don't do anything that would burn down the house.  )

[rollo]

   Tom this is a safe and tested method recommended by Audioquest. There is a technical explanation on AC by Ping Ping. He talks about back EMF to woofer. Nordst recommends the opposite diagonal hook up. Both sell bi-wires so certainly not a marketing ploy. I find it amazing after the demo.
     With third and fourth order crossovers not much of an improvement had.
   


charles

[tmazz]

I was in no way implying that what we were talking about was unsafe. I was just trying to say that in spite of all the theory and standard practices you should always let your ears be the final authority, except in a case where the better sounding way would result in a potentially damage to the equipment, the people using it or the room it was housed in.

And certainly there is nothing unsafe about rearranging the cables on a bi-wire configuration (unless you short them together which wouldn't result in very good sound since it would most likely wipe out your output devices. :)

[Werd]

I've always considered the start of the circuit at the load. In this case the load is the speakers. Then look back to the amp then preamp then source. Close the circuit and the speakers say I want power.  As opposed to the amp saying I am giving you power the speakers start the entire circuit.  So if you hook up a (+ - ) one direction to the woofer and one direction to the tweeter crossovers you 've effectively equalized the current draw from the amp. If you hook up the + and - to the woofer crossover only then the woofer becomes the dominant driver that talks to the amp.  The tweeter crossover will but it has to bear the resistance of the jumpers and the dominant load of the woofer. Current flow will take the easiest path and that path will be a woofer load. Of course the quality of the crossovers will make a difference but there will always be a bit of bullying by the woofer for current. This is negated by adding a lead direct to the higher crossover.

That's my guess lol

[tmazz]

Current flow will take the easiest path and that path will be a woofer load.

You can't make that statement without know the design of the speaker. speaker has an eight ohm woofer and a 4 ohm tweeter, assuming the crossover does  not add any substanial resistance the path of least resistance will be the tweeter circuit. And even this is very simplistic, because it is not a give that the imeodancce of either branch will be constant across the audio frequencies.

That said I have never really understood why bi-wiring sounds different execpt maybe because you have two runs of cable to the speaker. This certainly helps even even doing a shotgun run of ading a second cable to speakers that only have one set of terminals.  I have never had the chnace to try a shoutgun run and a jumper, vs. a true bi-wire setup to a speaker with multple termionals. Has anyone out there ever given this a try?