Randy Quad
Quadraphonic Survivor
well? what is the point? start at the beginning, what is it? 
:headscrat:
:headscrat:
bi-wire theory
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Raphael
Dream catcher.
Never done it but isn't it a two pair connection to source with one pairs + high-pass filtered before connecting to a speaker's high side and the other pair low-passed to the woof?
Also isn't this something you would only want to do with speakers that have unsophisticated or no x-overs?
Use the search tool 'cause I believe there is a defacto primer that details it all out quite well (or it may be a thread with a link).
Also isn't this something you would only want to do with speakers that have unsophisticated or no x-overs?
Use the search tool 'cause I believe there is a defacto primer that details it all out quite well (or it may be a thread with a link).
Scuzzer
Fixed Bias
Raphael- I think you are confusing bi-amping with bi-wiring
Bi-amping uses a line level crossover to feed individual amps for low and high ends, or in the case of tri-amping low/mid/high signals.
Bi-wiring removes the physical connection between the woofer/tweeter at the speaker and replaces it with 2 sets of wires that connect at the amp ouput.
As to the original question, I have no idea how this would make most speakers sound different or better since the only difference (as far as I can see) is the length of wire connecting the low and high sections of a passive speaker crossover.
Bi-amping uses a line level crossover to feed individual amps for low and high ends, or in the case of tri-amping low/mid/high signals.
Bi-wiring removes the physical connection between the woofer/tweeter at the speaker and replaces it with 2 sets of wires that connect at the amp ouput.
As to the original question, I have no idea how this would make most speakers sound different or better since the only difference (as far as I can see) is the length of wire connecting the low and high sections of a passive speaker crossover.
riverrat
professional camper
HERE is a write-up on biwiring and biamping. Pretty good low tech description.
My Totem Sttafs are set up with 2 sets of terminals so they can be biwired, but I don't have biwire cables yet. I will probably try some inexpensive homebrew biwires just because I can.
I did hear somewhere that biwiring was all the rage a few years ago, and that you don't hear as much about it nowadays. I also heard that many speaker manufacturers made their speakers biwirable just to please consumers who think that its a sign of quality.
As with all cable-related topics, you will probably hear wide variation in opinions.
My Totem Sttafs are set up with 2 sets of terminals so they can be biwired, but I don't have biwire cables yet. I will probably try some inexpensive homebrew biwires just because I can.
I did hear somewhere that biwiring was all the rage a few years ago, and that you don't hear as much about it nowadays. I also heard that many speaker manufacturers made their speakers biwirable just to please consumers who think that its a sign of quality.
As with all cable-related topics, you will probably hear wide variation in opinions.
Randy Quad
Quadraphonic Survivor
I am going to read riverrat's article. basically what is important to me at this point is that if speakers are set up to accept bi-wire they will still operate without it. did i gather that right?
i tried the search function but it only came up with two unhelpful threads. i'll google it more to get some correct facts. i just don't get the concept - does it create more resistance on the amp for the sake of what?
i tried the search function but it only came up with two unhelpful threads. i'll google it more to get some correct facts. i just don't get the concept - does it create more resistance on the amp for the sake of what?
Randy Quad
Quadraphonic Survivor
riverrat said:
great article. summed up just about all my questions.
spindoctor
Member
Biwiring
I biwire my Soliloquys and find it definitely enhances the sound, better bass, clear highs. Here's another reference with pics:
http://www.fluance.com/wiring.html#biwire
I biwire my Soliloquys and find it definitely enhances the sound, better bass, clear highs. Here's another reference with pics:
http://www.fluance.com/wiring.html#biwire
Bi-wiring is a marketing load of crap.
Bi/tri amping is a whole nother thing and could/would make a difference.
Bi/tri amping is a whole nother thing and could/would make a difference.
onplane
What! No Wake???
This guy has an interesting "theory" on bi-wiring and I have no idea whether this holds water or not.
In any event he says:
The primary reason sound quality changes with wiring topology is back EMF from the woofers. ... With some crossovers, back EMF from the woofers can pass through the crossover and enter the high frequency stage. ... Whether or not this is a problem depends on how large the back EMF is, the amount of attenuation provided, and the power spectral density of the music played.
Biwiring reduces back EMF effects by interposing the impedance of two runs of speaker cable between the stages. Since the power amp's output impedance is near zero, this change is a significant rebalancing of the network. Instead of the inputs of the speaker's treble section seeing the full back EMF voltage, most of the back EMF is absorbed by the amplifier before it gets to the treble section's terminals. Exactly how much attenuation this provides depends on the speaker, amplifier, cabling, and frequency of interest, but it's usually around 30 dB or so. ... If back EMF is significant, the result of biwiring or biamping is greater openness and clarity in the middle and high frequencies. "
http://www.rdrop.com/~/twest/audio/index.html
If this "theory" holds water, we'd expect to see the most benefit from bi-wiring in speakers that are somewhat inefficient. For it's those speakers that are drawing current that will have the highest probability of creating significant amounts of back EMF.
Again, I don't know whether this theory rests on sound scientific principles.
Regards,
Jerry
In any event he says:
The primary reason sound quality changes with wiring topology is back EMF from the woofers. ... With some crossovers, back EMF from the woofers can pass through the crossover and enter the high frequency stage. ... Whether or not this is a problem depends on how large the back EMF is, the amount of attenuation provided, and the power spectral density of the music played.
Biwiring reduces back EMF effects by interposing the impedance of two runs of speaker cable between the stages. Since the power amp's output impedance is near zero, this change is a significant rebalancing of the network. Instead of the inputs of the speaker's treble section seeing the full back EMF voltage, most of the back EMF is absorbed by the amplifier before it gets to the treble section's terminals. Exactly how much attenuation this provides depends on the speaker, amplifier, cabling, and frequency of interest, but it's usually around 30 dB or so. ... If back EMF is significant, the result of biwiring or biamping is greater openness and clarity in the middle and high frequencies. "
http://www.rdrop.com/~/twest/audio/index.html
If this "theory" holds water, we'd expect to see the most benefit from bi-wiring in speakers that are somewhat inefficient. For it's those speakers that are drawing current that will have the highest probability of creating significant amounts of back EMF.
Again, I don't know whether this theory rests on sound scientific principles.
Regards,
Jerry
Randy Quad
Quadraphonic Survivor
say you have bi-wired speakers with terminal sets 1 (high) and 2 (low) and your amp has two speaker outputs A and B. when you use both speaker outputs at once doesn't that split the power between the speaker terminals? the amp would be powering twice as many speakers right? so a 100 watt amp would put out 100 watts to speaker set A, but when both speaker sets are activated equal power would go to each set? doesn't that make sense? why do i know that i'm wrong? someone please teach me.
onplane
What! No Wake???
Randy Quad said:
First off, Randy, you can ONLY use speaker outputs A and B, if your amp puts those speakers in parallel. Many amps, when you select both A and B, will put those speakers in SERIES and ... that is NOT what you want!
Frankly, the simplest and safest way to bi-wire is to simply twist the two "hot" leads together and insert into the RED amp speaker output. Then twist the two return leads together and insert into the BLACK amp speaker output.
Make ABSOLUTELY certain that leads twisted together are "red to red" and "black to black". If you reverse this, due to cancellation, you will create "holes" in the frequency response at the xover frequencies.
Hope this helps ...
Regards,
Jerry
onplane
What! No Wake???
doyall said:
Sorry, doyall, but there is NO significant change in the load seen by an amp in a bi-wire (exact same drivers and passive xover network).
I guess one could argue that the NET resistance of the speaker wire is LOWER, since we have doubled the number of speaker wires. Nevertheless, this is still insignificant.
Regards,
Jerry
stuartk
Super Member
onplane said:
Not really, since the resistance provided to each crossover section is still that of one set of wire.
The Superposition Theorem is what's generally stated to prove bi-wiring is hooey.
"The total current in any part of a linear circuit equals the algebraic sum of the currents produced by each source separately."
KeninDC
Hazy Cosmic Jive
I bi-wired my B&Ws. For the incremental cost of speaker wire and an hour's worth of effort, I think ("think, think, think," said Pooh) I hear a subtle difference in clarity. Since it is done, I will not undo it, but there is no "wow" factor to bi-wiring IMHO. What follows is B&W's take on bi-wiring (and bi-amping):
http://www.bwspeakers.com/index.cfm.../ObjectID/F5CA2E9F-3D20-11D4-A67F00D0B7473B37
Ken
http://www.bwspeakers.com/index.cfm.../ObjectID/F5CA2E9F-3D20-11D4-A67F00D0B7473B37
Ken
Dougr33
Smoothing the Grooving
I don't KNOW anything, but I've heard more clarity when bi-wiring my speakers through the years (B&W 805, 803, Von Schweikert VR2). I've heard of two reasons it's beneficial. One is the back EMF from woofer section (which is also supposedly the benefit of the 'networks' found in MIT and Transparent Audio speaker cables). The other that did make sense (to me at least) was that while the wire is connected at one point to the amp, bi-wiring kept the stronger (watts) bass/mid(on my 2 1/2 way speakers; it would be bass and mid/treble on 3 ways) signal from traveling down the treble-connected wire where the signal was lower (watts) and thus more "delicate" and susceptible to smearing from the bass. NO idea if voodoo or not. But as I said, for me, it's been worthwhile.
Bi-amping makes sense to me as well, but only on a true 3-way system, which I haven't had yet.
Bi-amping makes sense to me as well, but only on a true 3-way system, which I haven't had yet.
