Two sets of wires to each speaker: Helpful or gimmick?

[gmgraves]

I can see bi-amping, whereby the two sections of the speaker in question are wired to two separate amplifiers, perhaps a nice, warm tube unit for the mids and highs and a beefy, low-output impedance solid state amp for the bass, but electrically, all you're doing with bi-wiring, AFAICS, is making the shorting bars between the two speaker systems longer. I.E. you are shorting the two speaker "halves" together at the amp end of things rather than at the speaker end. This, of course would increase the impedance on the entire lash-up. I can't see any advantage. Also if you bi-wire, rather than bi-amp, it would seem to me that both wires are carrying the entire frequency range. How do the wires going to the mid/tweeter know to only carry those frequencies, and do the wires going to the bass know to only carry those frequencies if both are connected to the same amplifier which is amplifying (hopefully) all frequencies equally? Can someone explain this to me? Thanks.

 

[gmgraves]

That's what I would think as well.

 

[ziggyzack]

Biwiring can only have a marginal effect - all you're doing electrically is moving the point where the conductors split from the amp to the speaker's crossovers. Although, some amps have two sets of terminals and say they're 'designed for biwiring', and furthermore, some manufacturers who do this like to distinguish themselves from the 'copycats' who merely stick on an extra pair of terminals in parallel - I've never worked out what they're doing that's so special though. Yet it's one of those areas where people often report great improvements.

 

Biamping (or multi-amping - you may have more than two drivers) is a different ballgame. It can be done passively, where the amps both take the same input, and have the same output, and the speaker's crossover is powered by the amp output. Or, it can be done actively, where a powered crossover splits the signal at line level, so each amp only has to work on a restricted frequency range, and there is no crossover interfering with the signal path between amp and speaker driver.

 

With multi-amping, you can get into dilemmas of vertical multi-amping or, I suppose it must be called horizontal multi-amping. Suppose you have two identical stereo amps, and speakers with two drivers. Do you use one amp per speaker, with one channel on each amp driving the bass and one driving the treble, so that the power load is spread evenly across each amp and you get absolute l/r separation? That's vertical. Or do you use one amp for left and right treble, and the other for left and right bass, so that the amp working the treble is completely unencumbered by bass duties? Or do you get a suite of mono-blocks? Decisions, decisions...

 

 

 

[Oystein]

I am a bit late to this "party" but I want to join in anyway

 

Most people think when looking at their bi-wiring connections at their speaker to bi-wiring only.

Bi-wiring itself gives hardly/or no any gain (looking at the cost/performance ratio) using double wiring.

We can debate the benefit of using silver wiring for the mid/highs and thick copper wiring for the lows. It might change the sound and gives more options tuning the sound by cables.

But adding the cost of 2 cable runs will likely get you better cables as single wires for the same money ... your choice.

 

Bi amping gives some other possibilities.

Using 2 identical amps will not change much.

But what about a tube power amp for the mid and high and a transistor power amp for the bass ?

This could be a "best of both worlds" solution but then again ... you have to buy 2 amps and 2 sets of cables.

What balance in cost/performance ratio will you get now ?

Unless your basement is full of unused gear and want to experiment.

 

In high-end the bi-wiring is hardly used ...

 

[Audio_ELF]

Bi-wiring ... bi-wiring can (to my mind / experience) actually have a beneficial effect, however there is some caveats...

 

The biggest improvement is usually from replacing the brass link bars with a short piece of cable. Either connect cable to one terminal, then link to the other, or get a cable made where there is a y-section on the end.

 

If you already have a single run of cable, adding a second run can make an improvement. However if you are buying completely new cable, it's usually better to buy a single run of more expensive cable than a bi-wire run of the cheaper.

 

Bi-amping is a different kettle of fish. The results often vary with different speakers. For example B&W and PMC often respond well to bi-amping (though again a single higher powered amp can be even better), where are Kudos tend not to make a jot of difference. Mixing and matchin amplifiers for the highs and lows can give interesting effects, but usually ends up with a muddled, misaligned in volume sound.

 

Eloise

 

[Bit Perfect]

John, I think it is you who is mistaken....

 

Bi-wiring runs two parallel runs of speaker cables from a single (or duplicated) set of amplifier terminals and as such each run of cable carries the full output signal of the amplifier not part of it. On arrival at the speaker each cable run hooks up to different parts of the crossover which are essentially hi or lo pass filters that only allow the appropriate parts of the signal to either the tweeter or bass unit.

 

If you disagree perhaps you could explain how the different parts of the signal leaving the amplifier know which cable run to travel along.

 

With bi-amping the crossover is located before the amplifiers, of which there are two (assuming the use of stereo amplifiers), so only part of he overall signal is routed through each amplifier/speaker cable.

 

As to the original question, my experience is that bi-wiring normally has some small benefit but not as much as bi-amping.

 

Personally, I've found that there is even more benefit by not having a crossover at all (and by definition only one run of speaker cable), which is why I use lowther full range speakers.

 

Ray

 

[Bit Perfect]

Whoops, I somehow missed most of the posts between the one I responded to and where we are now with this thread - sorry, I'll have a read through and catch-up on the other comments.

 

Ray

 

[Tipper]

 

Biamping, triamping in any configuration can give sonic benefits (not quite sure why one might want to use valves for one set of frequencies and solid state for another but….)

Then of course you have the cost of the amps and that will mean more boxes and that means more money and then all those expensive cables and a good quality pre amp and more cables and, and, and….

After all that you’ve still got the crossovers and it’s the crossovers that cause the problems with passive speakers.

Why not do the job properly and for a lot less money?

Even in a three way system a handful of carefully matched gainclones, or chip amps of your choice with one active crossover will probably give better results at a fraction of the cost.

 

I mean, why spend comparatively little money that gives much less clutter and complexity when you can spend a lot more on pretty boxes with enough cable to start your own power station and turn your living space into a coms centre look alike? Erm……something not quite right there…….

 

 

[John]

Ray, you could read the links I posted. If you don't want to do that; try not thinking of two sets of cables but two completely different A.C. circuits, one has a series resistor and one a series capacitor. Yes, they are both connected in parallel but that just means that they have the same voltage where they connect at the amp. The parallel circuits mean that there are two different paths for the current to travel and the speed at which the polarity changes is different on both sides of the filter component. Correct me if I am wrong. I don't care; I didn't write the articles. But, please, if you want to refute them provide and equally comprehensive alternate view. - John.

 

[Bit Perfect]

John, I've already followed up my post with an acknowledgement that I somehow missed a lot of the posts in this thread, including the one with your links in, and said sorry. I will read your links and the other posts a bit later when I have time to digest them properly.

 

Ray

 

[Face]

As long as a sufficient gauge is used from your amp to speaker, replacing the junk gold plated brass jumpers with something of higher quality will give almost if not just as much of a gain as bi-wiring.

 

[wgscott]

I'm ok with the physics and math, but I need to find some time to work through it. Thanks to everyone who has posted the links.