Benefit of bi-wire speakers? - Page 7 - AVS Forum | Home Theater Discussions And Reviews
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post #181 of 271 Old 07-17-2014, 02:47 AM
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Originally Posted by ALtlOff View Post
And I'm only doing the speakers that have individual driver connections instead of using the jumpers, if I had 12ga or larger wire or didn't have so much, I wouldn't bother
You MUST have the individual driver connections to buy-wire, and if you did not remove the jumpers you would be completely defeating the imaginary improvement gained by buy-wiring in the first place!
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post #182 of 271 Old 07-17-2014, 03:19 AM
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Originally Posted by jdcrox View Post
You MUST have the individual driver connections to buy-wire, and if you did not remove the jumpers you would be completely defeating the imaginary improvement gained by buy-wiring in the first place!
Lol, I only added that because of some of the thinking in this thread.....

Glad to see someone caught that right away....

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post #183 of 271 Old 07-17-2014, 03:31 AM
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The question that should of been asked, is what are you bi-wiring? Namely the make and type of speaker. Are we talking screen array speakers or Sony bookshelf speakers? Despite the haters, bi, tri, even quad amping does offer a significant improvement for loudspeakers, not so much for smaller home speakers. If the speaker is less than 6 feet tall, and has a build in crossover, i would not even worry about bi-amping it.
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post #184 of 271 Old 07-17-2014, 03:50 AM
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Yes, but that's amping not wiring, although, maybe that's part of the problem, some people either confuse the two or don't realise there's a difference.
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post #185 of 271 Old 07-17-2014, 05:52 AM
 
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Originally Posted by ALtlOff View Post
Yes, but that's amping not wiring, although, maybe that's part of the problem, some people either confuse the two or don't realise there's a difference.
Preventing that confusion is not aided at all by manufacturers of AVRs and speakers who promote 'passive' bi-amping, which also does not work.
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post #186 of 271 Old 07-17-2014, 08:01 PM
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Quote:
Originally Posted by CinemaAndy View Post
The question that should of been asked, is what are you bi-wiring? Namely the make and type of speaker. Are we talking screen array speakers or Sony bookshelf speakers? Despite the haters, bi, tri, even quad amping does offer a significant improvement for loudspeakers, not so much for smaller home speakers. If the speaker is less than 6 feet tall, and has a build in crossover, i would not even worry about bi-amping it.
Ok, but why the diagram about a subwoofer?

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post #187 of 271 Old 07-17-2014, 08:42 PM
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Originally Posted by psgcdn View Post
Ok, but why the diagram about a subwoofer?
The diagram is about bi-amping and how it is done. In simple speak, you are simply amping the output out of the crossover and directing it to each speaker in the cabinet, so the sub get's it's own amped input, and the mid/high range speakers get there own amped inputs. The downside is two sets of wires per speaker cabinet. like i said this is great for large venue/cinema/concert as each speaker gets it's own dedicated amp and power is not shared with other speakers in the cabinet, but not so convenient for home use. There is also tri-amping and quad amping, these two are rarely done in a home setup as $$$, wire runs and space needs can add up fast.
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post #188 of 271 Old 07-17-2014, 09:01 PM
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And for those who want to know about tri-amping. Here a a few diagrams that will make it easier to understand. And one picture clearly shows the jumper on the speaker connector that allow for a two wire connection, but you have just castrated, defeated or whatever you want to call it, the speakers design as it is a tri-amped speaker. Non of this is rocket science,but there are those who try to make it into rocket science.

And for those nay Sayers, how can you possible argue with the merits of having a single amp running each speaker versus one amp running several speakers? It's a no brainier.
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post #189 of 271 Old 07-17-2014, 09:38 PM
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Originally Posted by jdcrox View Post
You MUST have the individual driver connections to buy-wire, and if you did not remove the jumpers you would be completely defeating the imaginary improvement gained by buy-wiring in the first place!
I don't think it is a imaginary gain. Like all things electronics, performance is based on the set up and implication of the hardware. For those who do not have the ability, or simply understand what it is. i was suggest not using it, or research it before you tackle it. A fried $3,500 AVR is not something to think about.

It is not a secret that every speaker cabinet houses a crossover. It seems to be a big surprise when someone buys one that is intended for a bi-wired application.

To me bi-wiring is a simple way to get speakers with out a internal crossover to work. Some CE's do this just to slap "high end" or "Pro" on there products.
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post #190 of 271 Old 07-18-2014, 12:22 AM
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I hate to say it but I may have found a legitimate benefit to bi-wire... Future bi-amping.
If you think you may bi-amp in the future, go ahead and bi-wire now, esp. if your trying to do a nice clean wiring job, or if you have long hidden wiring runs, then it's already done and your not tearing up what you've already done.

Just a thought.
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post #191 of 271 Old 07-18-2014, 06:21 AM
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Originally Posted by ALtlOff View Post
I hate to say it but I may have found a legitimate benefit to bi-wire... Future bi-amping.
If you think you may bi-amp in the future, go ahead and bi-wire now, esp. if your trying to do a nice clean wiring job, or if you have long hidden wiring runs, then it's already done and your not tearing up what you've already done.

Just a thought.

That would make sense if, in fact, there were any benefit to passive biamplification.
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post #192 of 271 Old 07-18-2014, 06:23 AM
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Originally Posted by CinemaAndy View Post
I don't think it is a imaginary gain. Like all things electronics, performance is based on the set up and implication of the hardware. For those who do not have the ability, or simply understand what it is. i was suggest not using it, or research it before you tackle it. A fried $3,500 AVR is not something to think about.

It is not a secret that every speaker cabinet houses a crossover. It seems to be a big surprise when someone buys one that is intended for a bi-wired application.

To me bi-wiring is a simple way to get speakers with out a internal crossover to work. Some CE's do this just to slap "high end" or "Pro" on there products.

I think you are discussing active bi-amping, not bi-wiring. This thread is about bi-wiring. Bi-wiring is just adding another pair of wires, no extra active devices, no eliminating any crossovers, etc. The benefits of active bi-amplification are well-known and have been discussed in many threads. Bi-wiring and "passive" bi-amplification as implemented by many AVRs has few if any real-world benefits (and not many theoretical ones for that matter).

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post #193 of 271 Old 07-18-2014, 06:47 AM
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Originally Posted by CinemaAndy View Post
I don't think it is a imaginary gain. Like all things electronics, performance is based on the set up and implication of the hardware. For those who do not have the ability, or simply understand what it is. i was suggest not using it, or research it before you tackle it. A fried $3,500 AVR is not something to think about.

It is not a secret that every speaker cabinet houses a crossover. It seems to be a big surprise when someone buys one that is intended for a bi-wired application.

To me bi-wiring is a simple way to get speakers with out a internal crossover to work. Some CE's do this just to slap "high end" or "Pro" on there products.
Huh? Of all the pictures you have uploaded, two are about bi-wiring speakers. The best is "Fig 2" on this last batch. The only difference bi-wiring does in that diagram is the current draw is different in each of the two wire pairs. The load on the amp is the same. The effect of clipping is the same.

Now you say that bi-wiring is used on speakers without an internal crossover?

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post #194 of 271 Old 07-18-2014, 06:49 AM
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Originally Posted by FMW View Post
That would make sense if, in fact, there were any benefit to passive biamplification.
Personal I'm going to give Bi-Amping a try simply from a power standpoint, my main speakers are notoriously power hungry, so I figure it won't cost that much to add a few mono-blocks into the mix, basically running a discrete 125w from the AVR to the highs, and 125w from the mono-blocks to the mids, instead of just the AVR's 125w to the entire array. Figure it's worth a try anyway, besides, playing with this stuff is half the fun anyway....
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post #195 of 271 Old 07-18-2014, 07:07 AM
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Most amps are voltage-limited so when you apply a full-range signal from the AVR to both amps they clip at the same point. That is how "passive" bi-amping works in most AVRs. No power gain. None in any event unless you get a bigger amplifier... If you have one 100 W amplifier the max power any speaker will see is 100 W. If you split the signal into highs and lows at the speaker and use two 100 W amps, the max power any driver sees is still 100 W. If you use an active crossover the treble amp may deliver less power depending upon the crossover point and source signal, providing some headroom benefits with an actively bi-amplified system, but there is still no actual max power increase unless you add a bigger amp. For a passively bi-amped system you don't even get that headroom gain since both amps get the same input signal and thus clip at the same (voltage) point. You may get some headroom gain in output current, but that is not what usually limits the average amplifier so you won't notice it in the real world.

If you want more power, buy a bigger amp.

For reference, in the midrange 1 dB is a just-noticeable increase (or decrease) in volume for most people. Chances are in the middle of a song if someone bumps the volume by 1 dB you wouldn't notice. 1 dB up requires 1.26x the power. If you bump the volume just slightly louder ("turn it up a hair"), that is about 3 dB for most of us, and requires 2x (twice) the power. Making it sound twice as loud requires about 10 dB, a power increase of 10x. So, if you really need more power, chances are you need a lot more to make a difference...

There are a myriad of threads on this with plenty of believers on both sides. The science is against any real-world benefit to bi-wiring or passive bi-amping in the vast majority of cases. Of course, the average audiophile is an exceptional case, at least in their mind... I played this game before I really understood it, spouting and believing I heard all the usual audiophile stuff. Gaining engineering knowledge plus participating in a number of blind tests was humbling to say the least. At least now I know where to spend my money to make a real difference. As an aside, sometimes real differences pop up, and then my goal is to figure out what and why.

If you want to try anyway, I suggest picking up an active crossover to go before your amplifiers. That way you can at least take advantage of the theoretical benefits, though in a blind test chances are you would not notice. Much of the benefit of bi-amping comes from tighter coupling of the amp to the driver, which means bypassing the speaker's internal crossovers, which means implementing a better one electronically. DSP has made that easier, but it is generally not a task for a novice.

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post #196 of 271 Old 07-18-2014, 07:27 AM
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Originally Posted by CinemaAndy View Post
And for those nay Sayers................
You will not find too many naysayers around here with regards to the true active biamplification you are promoting. Budget and skill permitting, I doubt anyone would disagree.

But, as pointed out, you are conflating bi-wiring, 'passive' bi-amplification, and active bi-amplification.
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Originally Posted by ALtlOff View Post
I hate to say it but I may have found a legitimate benefit to bi-wire... Future bi-amping.
Bi-amping requires removal of the passive crossover from the speaker, and an electronic crossover prior to amplification. So-called 'passive bi-amping' using an unused set of AVR amps doesn't do that.
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post #198 of 271 Old 07-18-2014, 12:11 PM
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Originally Posted by ALtlOff View Post
Personal I'm going to give Bi-Amping a try simply from a power standpoint, my main speakers are notoriously power hungry, so I figure it won't cost that much to add a few mono-blocks into the mix, basically running a discrete 125w from the AVR to the highs, and 125w from the mono-blocks to the mids, instead of just the AVR's 125w to the entire array. Figure it's worth a try anyway, besides, playing with this stuff is half the fun anyway....

Whatever makes you happy. No need to justify the unjustifiable to me.
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post #199 of 271 Old 07-18-2014, 04:35 PM
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Originally Posted by FMW View Post
That would make sense if, in fact, there were any benefit to passive biamplification.
Spoken like a true Nay Sayer. Next time you hit a cinema or concert up, check to see how that "Awesome" sound is getting to your ears. Passive bi-amping.
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post #200 of 271 Old 07-18-2014, 04:41 PM
 
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Spoken like a true Nay Sayer. Next time you hit a cinema or concert up, check to see how that "Awesome" sound is getting to your ears. Passive bi-amping.
Cinemas and concerts, ie., pro-sound gear, do not use passive bi-amping.
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post #201 of 271 Old 07-18-2014, 04:54 PM
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Huh? Of all the pictures you have uploaded, two are about bi-wiring speakers. The best is "Fig 2" on this last batch. The only difference bi-wiring does in that diagram is the current draw is different in each of the two wire pairs. The load on the amp is the same. The effect of clipping is the same.

Now you say that bi-wiring is used on speakers without an internal crossover?
That is because to me bi-wiring always leads to bi-amping. It's a natural progression. The wires are in place, just add the amps. If you are using the AVR amp, no matter the brand, you are doing it wrong. All AVR's have a X spot that the amp will clip at.

Yeah, not every speaker cabinet made comes with a internal crossover. Bi-wiring has always been the "cheap" or "easy" fix for that.

I don't know about everybody else, how can you just bi-wire and walk away?
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post #202 of 271 Old 07-18-2014, 05:01 PM
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Originally Posted by Bill Fitzmaurice View Post
Cinemas and concerts, ie., pro-sound gear, do not use passive bi-amping.
Oh really?

This is what Klipsch has to say about it,

http://www.klipsch.com/Education/bi-amping
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post #203 of 271 Old 07-18-2014, 05:11 PM
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Originally Posted by CinemaAndy View Post
Oh really?

This is what Klipsch has to say about it,

http://www.klipsch.com/Education/bi-amping
Yes really. Do you understand the difference between active and passive biamplifiaction? I'd do some reading and it will become clear to you.
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post #204 of 271 Old 07-18-2014, 05:14 PM
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Originally Posted by CinemaAndy View Post
Oh really?

This is what Klipsch has to say about it,

http://www.klipsch.com/Education/bi-amping

Directly from that link you provided:

"True bi-amping involves hooking each amplifier to an electronic crossover that serves to supplant the passive crossover network built into the speaker (the passive crossover must be eliminated in order to achieve the advantages of bi-amping). This “active crossover” then connects to the appropriate speaker terminals; one for the woofer and another for the combined mid and high ranges."
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Do you understand the difference between active and passive biamplifiaction? .
No i don't have enough post's yet.
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post #206 of 271 Old 07-18-2014, 06:16 PM
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Just... wow.
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post #207 of 271 Old 07-19-2014, 12:23 AM
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LOL...this thread proves it!

Zombies cause havoc...and quickly....

This thing had been dead for two years up until a couple of days ago....
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post #208 of 271 Old 07-19-2014, 11:47 AM
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Originally Posted by CinemaAndy View Post

Yeah, not every speaker cabinet made comes with a internal crossover. Bi-wiring has always been the "cheap" or "easy" fix for that.
You are correct. Only about 90% of all consumer speaker cabinets have internal crossovers of some type. The main exception would be full-range, single-driver speakers. Even if it is only a simple cap, there is generally a crossover in speakers. And how would bi-wiring be any sort of a "fix" for an internal crossover, since it is still in place and utilized even if you remove the jumpers?
And I really agree, you need to study up on the difference between passive and active bi-amping.
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post #209 of 271 Old 07-19-2014, 02:43 PM
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Originally Posted by jdcrox View Post
And I really agree, you need to study up on the difference between passive and active bi-amping.
Bi-wiring

Bi-wiring requires speakers with two pairs of binding posts for speaker wire. Many upscale loudspeakers now come with this configuration, including a removable shorting bar that connects the two "+" and the two "-" terminals for use with normal, single pair, speaker wire. One set of binding posts connects to the high frequency side of the passive crossover inside the speaker box and the other set of binding posts connects to the low frequency side of the crossover. The shorting bar (when left in place) insures that both sides of the crossover receive the same input signal.

Remove the shorting bar and the speaker is ready for bi-wiring. This procedure runs two lengths of two-conductor speaker wire in parallel from the power amplifier's output to the dual binding posts on the loudspeaker. Note that these dual speaker wires are shorted together at the amplifier end; thus, both speaker cables are carrying the same signal from the amplifier to the loudspeaker. One speaker wire is attached to the high frequency side of the speaker's crossover binding posts and the other is attached to the low frequency side. It doesn't matter which wire pair goes to which side of the crossover, since both are identical. The result is both sides of the crossover getting the same, identical signal, just as it would if the shorting bar were in place and both sides of the crossover were fed by one speaker cable.

A reasonable question at this point would be, "Since, either way, the speaker is receiving the same signal, how is this supposed to improve the sound?" This is a logical question and, as long as the speaker wires are identical in length, type and gauge, there should be NO effect on the sound of the loudspeaker. Bi-wiring with identical speaker cables accomplishes nothing, at least from the music listener's perspective.

However, it does accomplish something from the cable manufacturers and retailers standpoint: it doubles their profit on cables, which are already the most profitable item in the store. This last point is sweetened by the fact that it is the most extreme audiophiles, often with more money than electronics knowledge, who are likely to bi-wire and buy the most expensive speaker cables. For example, a pair of 10 foot Audioquest Flat Rock Series K2 speaker cables suitable for bi-wiring (two "+" and two "-" speaker connectors per cable) carries a MSRP of $10,450.

Folks with scant technical knowledge and lots of blind faith report sonic improvements with bi-wiring. This is known as the placebo effect in medicine. Empirical testing would reveal that bi-wiring is a waste of effort and money.

Bi-wiring could be used to alter the sound of a loudspeaker by using different speaker cables. Use 10 feet of 12 AWG line cord to connect the amplifier to the low frequency side of the speaker and 100 feet of 24 gauge zip cord to connect the amp to the mid/high frequency side and the result should be decreased mid/high output, due to the increased wire loss. This would be a crude way to "correct" overly bright loudspeakers, but it would be easier, tidier, cheaper and more effective to use the tone controls provided on most control amplifiers.

Passive bi-amping

Passive bi-amping (also known as "fools bi-amping" for good reason) requires loudspeakers with the dual binding posts used for bi-wiring, again with the shorting bar removed. The difference (and profit advantage for the retailer) is that it requires two stereo power amplifiers, instead of one, and an additional pair of speaker cables. (Can you guess who is getting fooled by passive bi-amping?)

In passive bi-amping, the output from the pre-amplifier is fed to a pair of identical stereo power amps. All four amplifier channels are fed the same, full range, signal from the pre-amp. This is important, so take note of it. The output of the power amps is fed to the stereo loudspeakers, the left and right outputs of one power amp to the left and right loudspeakers' high frequency binding posts and the left and right outputs of the other power amp to the left and right loudspeakers' low frequency binding posts. We now have the same, full range signal everywhere. The high frequency part of each loudspeaker's passive internal crossover is doing what it always does with a full range signal, as is the low frequency part of each loudspeaker's crossover.

From the listener's perspective, if all goes well, the sound quality should remain exactly the same. However, the placebo effect insures that most folks who passively bi-amp their music systems report a sonic improvement. The system's total amplifier power has been doubled, which is probably a good thing and may actually result in a sonic improvement at high listening levels. However, if doubling the system's amplifier power is necessary, it would be cheaper to buy (for example) one 200 watt stereo amplifier than two 100 watt stereo power amps of the same quality to get the same result.

Active bi-amping

What is now called "active bi-amping," to differentiate it from passive or fool's bi-amping, used to be just "bi-amping." Unlike bi-wiring and passive bi-amping, active bi-amping has definite and provable benefits. Unlike the sham bi's, real bi-amping sends one signal to the woofer and a different signal to the tweeter in a two-way loudspeaker system. This requires two stereo power amps (or four monoblock amplifiers). Perhaps I should interject that bi-amping is for two-way loudspeakers (woofer and tweeter). A three-way loudspeaker system (woofer, midrange, tweeter) would require tri-amping (three stereo power amps).

Here is how bi-amping works, using one stereo pre-amp and two stereo power amps. The full range, left and right signals from the pre-amplifier are fed to an outboard (also called "active") crossover. This crossover splits the low and high frequency information for the two stereo channels. The L/R high frequency output is fed to one stereo power amplifier and the L/R low frequency output is fed to another stereo power amplifier.

Note that the active crossover is between the pre-amp and the power amps, not inside the speaker box. The active crossover has two (left and right channel) inputs and four signal outputs (left channel high frequency, right channel high frequency, left low frequency and right low frequency). Also, notice that the two stereo power amplifiers are being fed, and will amplify, different signals representing only part of the original (full range) signal.

The stereo power amp handling the right and left high frequency signals is connected directly to the right and left tweeters, NOT to the speaker systems' internal passive crossovers. The power amp handling the right and left low frequency signal is connected directly to the right and left woofers. The loudspeakers' internal passive crossovers have been bypassed and are disconnected from the system's drivers. The passive crossovers may be physically removed from the speaker cabinets, if desired.

Active bi-amping has several advantages. Since each power amp is driving only part of the frequency spectrum, intermodulation distortion is virtually eliminated. The inevitable power loss associated with a passive crossover is eliminated. Since the low frequency driver (woofer) requires the bulk of the power in any speaker system, a less powerful amplifier may be used to drive the tweeters in a bi-amped system. (Of course, there must be level controls on the active crossover to balance the system.) The power amps are not working as hard to drive a bi-amped speaker system to any given volume, so harmonic distortion is reduced and clipping at high volume is unlikely. The stereo system's amplifier power is effectively doubled. The benefits of active bi-amping are real (not subjective) and can be measured with test equipment.

In the real world, there is no free lunch and this remains true for active bi-amping. The most obvious drawback is increased expense, since two stereo power amps and an outboard crossover are required, not to mention four sets of speaker wires. System complexity is increased and there are more interconnects (patch cords and speaker cables). In addition, the active crossover must match the characteristics of the speaker system to be bi-amplified and usually must be custom built. If you are considering bi-amping to take advantage of the increased system power from dual power amps, let me point out that it would be cheaper and much simpler to buy a single stereo power amp with twice the power and use it conventionally

To set-up a bi-amped loudspeaker, test equipment is required, along with the knowledge to use it correctly. At a minimum, this means a sound pressure level (SPL) meter and a test CD with a sine wave test tone at the crossover frequency. Much better is a sine wave test tone generator, and these are not cheap..

Yes, IT IS ALL GOOD.
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post #210 of 271 Old 07-19-2014, 09:23 PM
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You forgot to quote your source:

http://www.chuckhawks.com/bi-wire_bi-amp.htm
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