Biwire/Biamp Questions

Had the VHS, then when the DVD came out I bought it too..
 
Yep, you're coming right along with this Phoenix thing...
 
Lazarus Short said:
I had thought biamping would be a simple matter of connecting the tape outs of one amp to an input of a second amp, and adjusting levels to match with the gain controls. Biwire looks safer, cheaper, and less complicated...
Click to expand...

Unfortunately not. Beter use the MAIN outputs of your pre' or simply use a "Y" connector.
 
I gleaned this off the Vandersteen website - it was in the very long-winded FAQ section:

Bi-wiring uses two separate sets of speaker cables to connect a single pair of loudspeakers to an amplifier. Coupled with a crossover designed specifically for bi-wiring, it offers many of the advantages of bi-amplifying the speakers with two separate amplifiers without the cost and complexity of two amplifiers.
We began experimenting with bi-wiring back in the early '80s, an era when horizontal bi-amplification was considered the ultimate way to drive quality loudspeakers. (Horizontal bi-amplification used one amplifier to drive the low-frequency section of a speaker and a second amplifier to drive the high-frequency section.) We noted that speakers sounded better when bi-amplified by two amplifiers than when driven by a single amplifier. Surprisingly, this superior performance was evident even when the speakers were bi-amplified by two identical amplifiers at a low volume level and the amplifiers were each driven full-range without an electronic crossover. We initially believed that the double power supplies and other components of two amplifiers were responsible for the improvement, however building amplifiers with twice the power supply and doubling-up on other critical components failed to provide the bi-amplification benefit.
So we looked at the speaker wires. With two amplifiers, bi-amplification used two sets of speaker cables so we experimented with doubling-up the speaker wires and with larger wire. Neither duplicated the bi-amplification improvements. Then we considered that in a bi-amplified system, one set of wires carries the low-frequencies and the other set of wires carries the high-frequencies. We modified a speaker's crossovers to accept two sets of cables and present different load characteristics to each set so that the low-frequencies would be carried by one set of wires and the high-frequencies by the other set of wires. Finally we heard the sonic improvements of bi-amplification with a single amplifier.
Additional experiments with a Hall Effect probe revealed that high-current bass frequencies created a measurable field around the wires that expanded and collapsed with the signal. We believe that this dynamic field modulates the smaller signals, especially the very low level treble frequencies. With the high-current signal (Bass) separated from the low-current signal (Treble) this small signal modulation was eliminated as long as the cables were separated by at least an inch or two. (To keep the treble cable out of the field surrounding the bass cable.)
The crossovers in Vandersteen bi-wirable speakers are engineered with completely separate high-pass and low-pass sections. The bass inputs pass low-frequencies to the woofers, but become more and more resistive at higher frequencies. The treble inputs pass high-frequencies to the midrange and tweeter, but become more and more resistive at low-frequencies. The output from the amplifier always takes the path of least resistance so deep bass frequencies go to the bass input (Low impedance at low-frequencies) rather than to the treble inputs (High impedance at low frequencies). For the same reason, treble frequencies go to the treble input (Low impedance at high-frequencies) rather than to the bass inputs (High impedance at high-frequencies). At the actual crossover frequency, the output from the amplifier would be divided equally between the two inputs as they would both have the same impedance at that frequency. Because of the different reflected impedances of the cables, the crossover between the woofer and midrange actually occurs at the wire ends where they connect to the amplifier.
The benefits of bi-wiring are most obvious in the midrange and treble. The low-current signal to the midrange and tweeter drivers does not have to travel on the same wire as the high-current woofer signal. The field fluctuations and signal regeneration of the high-current low-frequencies are prevented from distorting or masking the low-current high-frequencies. The back EMF (Electro-Mechanical Force) from the large woofer cannot affect the small-signal upper frequencies since they do not share the same wires.
The effects of bi-wiring are not subtle. The improvements are large enough that a bi-wire set of moderately priced cable will usually sound better than a single run of more expensive cable.
All the cables in a bi-wire set must be the same. There is often great temptation to use a wire known for good bass response on the woofer inputs and a different wire known for good treble response on the midrange/tweeter inputs. This will cause the different sonic characteristics of the two wires in the middle frequencies to interfere with the proper blending of the woofer and midrange driver through the crossover point. The consistency of the sound will be severely affected as the different sounding woofer and midrange drivers conflict with each other in the frequency range where our ears are most sensitive to sonic anomalies. The disappointing result is a vague image, a lack of transparency through the midrange and lower treble and a loss of detail and clarity.
Some of the benefits of bi-wiring are from the physical separation of the high-current bass and low-current midrange/tweeter wires. So-called bi-wire cables that combine the wires in one sheath do not offer the full advantages of true bi-wiring although they may be an excellent choice for mono-wiring the speakers.
The cables should all be the same length. This is not due to the time that the signal takes to travel through a cable, but rather that two different lengths of the same cable will sound different. If the cables connecting one speaker are a different length than the cables connecting the other speaker, the resulting difference in sound between the two speakers will compromise the imaging and coherence of the system. If different lengths of cable are used for the bass and midrange/tweeter inputs of the speakers, the effects will be similar to those experienced when using two different cables as described above.
Since short runs of speaker cable sound better than long runs, consider placing your electronics between the speakers rather than off to one side. If for convenience or aesthetic considerations, the electronics must be located a considerable distance from the speakers, it is usually preferable to place the amplifier between the speakers and use long interconnect cables and short speaker wire.

Laz: What do you folks think? Good information or technobabble?? Mike advised me to stick with my current single wire + double ganged banana setup, BTW.
 
Buy 100' of 12 gauge speaker cable and do some experimentation....the Vandersteens are bi-wire capable??
 
Honestly, the whole concept of bi-wire sounds like bovine scat to me.

"Then we considered that in a bi-amplified system, one set of wires carries the low-frequencies and the other set of wires carries the high-frequencies"

If both set of wires are connected to the same amplifier, both are carrying the full audio range to the crossover. The only wires anywhere that are only carrying a partial range are the ones between the crossover and the driver itself. In most speaker systems, thats what, 2 feet of wire? If the crossover lived next to the amp and the long runs were between the crossover and the drivers, I'd maybe buy it. I won't say that its impossible to hear a difference, but I do not buy the explanations of why it may happen.
 
There are some speakers out there with tri-wire capability. :D

My Definitive Techs allow for tri-wiring, but you would probably need to bi or tri amp them to do it.


definitive_technology_bp2000_tl_bipolar_speakers_with_power_subwoofer___pair_6_lgw.jpg
 
Hi Laz. I kind of suggested the same to you that Lee just mentioned when you were here. Remember you were listening
to a BI-AMPED set-up with an electronic crossover between the pre-amp and amps. Not bi-wire.
If you look at the back of the speaker Web just posted, with jumpers its fine with just one set of wires? Or remove
the jumpers and run more wires?
Bi-wiring (tri wiring) is considered in the top ten of audiofool b.s. Its sells more product ,great for the Best Buy salesmen.
Now if you spent some serious green on two sets of super wires, sure will will try to convince yourself it sounds better.:toothy10:
Can it hurt your system? No.
I have a hard time convincing my wife that one set is needed running across the floor and up the walls.:sign11:
 
JustMike said:
Hi Laz. I kind of suggested the same to you that Lee just mentioned when you were here. Remember you were listening
to a BI-AMPED set-up with an electronic crossover between the pre-amp and amps. Not bi-wire.
If you look at the back of the speaker Web just posted, with jumpers its fine with just one set of wires? Or remove
the jumpers and run more wires?
Bi-wiring (tri wiring) is considered in the top ten of audiofool b.s. Its sells more product ,great for the Best Buy salesmen.
Now if you spent some serious green on two sets of super wires, sure will will try to convince yourself it sounds better.:toothy10:
Can it hurt your system? No.
I have a hard time convincing my wife that one set is needed running across the floor and up the walls.:sign11:
Click to expand...

Yes, I remember you telling me all that. My question a few posts ago, with the long quote from R.V., was whether what he said was technobabble or not, especially the part about Hall effect. I suspect it is, but want confirmation. When time allows, I will do the biwire bit myself and satisfy my curiosity...
 
I only use one set of wires. I have never tried bi-wires or bi-amping as one wire and one amp sounds pretty dam good to me.
 
gadget73 said:
Honestly, the whole concept of bi-wire sounds like bovine scat to me.

"Then we considered that in a bi-amplified system, one set of wires carries the low-frequencies and the other set of wires carries the high-frequencies"

If both set of wires are connected to the same amplifier, both are carrying the full audio range to the crossover. The only wires anywhere that are only carrying a partial range are the ones between the crossover and the driver itself. In most speaker systems, thats what, 2 feet of wire? If the crossover lived next to the amp and the long runs were between the crossover and the drivers, I'd maybe buy it. I won't say that its impossible to hear a difference, but I do not buy the explanations of why it may happen.
Click to expand...

Each of the bi -wires pairs carry the full voltage that is output by the amp but NOT the full current that is output by the amp. That is an important distinction in this discussion. The pair going to the woofer only carries the woofer current and the tweeter pair only carries the tweeter current
 
Cirrent is more responsible for the Hall effevt IIRC...
 
What I've always done in my bi-amping systems, is use the same "beefy amps" for both the lows AND the highs. Now this refers to the 700B's with trim pots. This enables me to have matching amps, without damaging my highs. I can turn the pots down on the highs and then click the -20db switch to get matching meter movement with my lows amp that is NOT switched with the -20db switch. Most of the time the meters move in tandem and I do get the sonic desired result. It saves me from having to use a PL400 or different amp that I cannot control. Logic may say that if I am going to turn down the pots then why have a 700B on the highs? Well in my peculiar world, I just prefer the sight of two beautiful 700B's.

That brings me to an actual question. Could someone please school me on the abilities or non abilities of BRIDGING? I understand the concepts of it already in car audio because I could do it on those amps; but I'm dead dumb of the home amps ability to do so? I think I read somewhere here that's a big NO-NO on the Phases. Keep in mind I have a bi-amp system, so my idea would be to try and make one amp a whole left channel and the other a right channel. (mono amps if you will) Thus creating the need for FOUR amps. Two on the low, two on the high. Its just an experiment and a fun "how to"? idea I have tossing about. Educate me gents! :-) I also know Lee was working on a big fat MONO block phase linear amp in another thread? I wonder if that's still going on...............
 
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