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I've read past threads and still trying to grasp the concept that seems to appear that passive bi-wiring / bi-amping makes no difference in speakers (subjectively).


I have a older denoon 4308 I plan to use on a pair of Revel C52 Center Speakers The speakers will be used in a 2.1 setup . Still trying to understand and learn why there is no difference/benefit on passive bi-amping / bi-wiring the speakers per prior posts suggest.


Love to get a simplified laymans terms for a speaker/AVR noob.


TIA
 

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Biwiring means using two wires. It's a silly idea IMO. Just use one bigger wires. So I will discuss it no further (and you can read articles online where electrical engineers dismiss it as well.)


Passive biamping might make sense if you happen to have two stereo amps lying around. Let's say you don't, though, and you are considering whether to buy amps.


Given that this is passive, you will send two mostly identically amped signals to your speaker. One signal will be high passed, and the other low passed. You just wasted the power needed to amplify the part of the signal that was filtered out by the low and high pass portions of the crossover. So buying two amps just to have part of their power wasted seems silly to me.


With active biamping, you only amplify what will be needed. You have a speaker with no crossover, or a disconnected crossover. You send a low passed, LINE level signal to the "low" amp, and a high passed LINE level signal to the "high" amp. Each amp amplifies the signal and is directly connected to the proper driver (there might still be a crossover in the case of 2-way active biamping and a 3-way speaker, such as to crossover the mid/tweeter.)


So yes, there seems to be a benefit to active biamping, where passive biamping appears to waste power.


Now for receivers, where you already have the capability, I would guess it's even more pointless as a general rule. You are loading the same shared power supply with two amps rather than one. Where is the extra power coming from? You are drawing from the same limited resource.


There is a scenario where it could help, I guess. Let's say you were clipping on a stereo signal because you were hitting your rail voltage limitation. If biamping got around that, maybe biamping would help. Some people have used bimaping and liked the results. No way to tell if they invented the improvement in their head, or not.


Feel free to chime in if you know differently.
 

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Funny thing about the passive/active biamp discussion is that most every speaker manufacturer recommends Passive biamping because that method still utilizes the speakers internal crossovers that their engineers spent quite a bit of time carefully designing to work with the given driver and enclosure package. I fail to completey understand how any amount of wasted amplifier power isn't offset by many other advantages utilizing this method. Maybe someone who has worked with amplifier design can enlighten us.


Found this article that explains it pretty well- http://www.padrick.net/LiveSound/Biwiring/Biwiring.htm
 

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The amplifier power isn't wasted electrically. The builtin passive filters provide a high impedance load outside their bandpasses. In other words, the high-pass filter used for a tweeter draws very little power at low frequencies and the low-pass filter used for a woofer draws very little power at high frequencies.


Tweeters are more efficient than woofers. In principle, one could use a lower powered amp to drive a tweeter than one would use to drive a woofer, so in that sense one might be considered to be wasting power if one uses an unnecessarily high-powered amp to drive a tweeter.


One does have to use amps with identical gains for both the tweeter and woofer channels. Otherwise you need to compensate by introducing some kind of equalization in order to ensure that both tweeter and woofer produce appropriate sound levels. Using a stereo amp for the two channels is the easiest way to ensure both channels have equal gain, even though the channel used for the tweeter is unnecessarily powerful.
 

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If you have the extra amplifiers available and would not otherwise be using them, you may as well hook them up for bi-amping, even if it's passive. You've really got nothing to lose by trying it out. Just don't expect a big difference (or even a noticeable one).


If you're thinking about buying amps for bi-amping, just buy bigger amps (or more efficient speakers) instead.


Bi-wiring is generally just a waste of time and money. The only time you would benefit from that would be if the gauge of your existing wire is insufficient to carry the required current. The best solution would be to replace the wire with thicker wire. However, you could also run a second set of wires parallel to the existing ones and get a similar effect. For example, a pair of 16 gauge wires combines to produce an effective gauge of about 13.


That said, I can imagine some cases where two sets of thinner wires may be easier to work with during installation, such as negotiating tight turns in confined spaces.
 

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Quote:
Originally Posted by StevenC56 /forum/post/18173564


Funny thing about the passive/active biamp discussion is that most every speaker manufacturer recommends Passive biamping because that method still utilizes the speakers internal crossovers that their engineers spent quite a bit of time carefully designing to work with the given driver and enclosure package. I fail to completey understand how any amount of wasted amplifier power isn't offset by many other advantages utilizing this method. Maybe someone who has worked with amplifier design can enlighten us.


Found this article that explains it pretty well- http://www.padrick.net/LiveSound/Biwiring/Biwiring.htm

I am supposed to trust a guy who suggests biwring and is not joking?
I understand you need to use two wires to biamp, but he seems to be suggesting there's an improvement even if you don't biamp?


In any case, there are still issues with passive biamping, I think.


One there's an extra box (if using amps)


Two, in some cases (not all,) it's more expensive (if using amps)


Three, in some speakers, the high input might require a substantiallly lower power than the low input to drive to the same SPL, so two 100 watt amplifiers might be a bad idea (based on some articles I have read on the average power needed for the tweeter vs. woofer, and assuming a two way speaker.)


Four, if you have a receiver, the fact that the power supply is shared, would likely seem to result in no more power.


Of course, in the OPs case, testing whether biamping will improve his sound is simple enough, so he should do it.
 

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Quote:
Originally Posted by MichaelJHuman /forum/post/18174845


I am supposed to trust a guy who suggests biwring and is not joking?
I understand you need to use two wires to biamp, but he seems to be suggesting there's an improvement even if you don't biamp?

Many things in Audio/Video are subjective. When I went from single to biwire on my Kappa's I thought there was a very slight improvement in sound. Maybe there really wasn't, however I perceived that there was a positive change. When I passive biamped my Kappas there was a definite improvement to my ears. Even if somebody else thinks I've wasted money upgrading or tweaking my system an any way, it is my system and money after all. To each his own.
 

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Some things are subjective. Some claims defy physics though
Like biwiring. Or expensive power cables. Lots of stuff. I trust physics, because it's not trying to sell me something
 

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Quote:
Originally Posted by MichaelJHuman /forum/post/18174960


Some things are subjective. Some claims defy physics though
Like biwiring. Or expensive power cables. Lots of stuff. I trust physics, because it's not trying to sell me something

Is there really any proof one way or another about a speaker wire design carrying certain frequencies more efficiently than others? As is true with any hobby-Sometimes cool stuff is just that, and nothing more.
 

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Quote:
Originally Posted by StevenC56 /forum/post/18175460


Is there really any proof one way or another about a speaker wire design carrying certain frequencies more efficiently than others? As is true with any hobby-Sometimes cool stuff is just that, and nothing more.

lol, more efficiently???


Is that like asking if some speaker wires make the notes lighter and they just jump



Which stick to science if we are going to discuss it all and leave the subjective banter to audiofools
 

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Quote:
Originally Posted by MichaelJHuman /forum/post/18174960


Some things are subjective. Some claims defy physics though
Like biwiring. Or expensive power cables. Lots of stuff. I trust physics, because it's not trying to sell me something

Yes I agree Bi-wiring just looks good, I guess the big advantage of Bi-amping is providing more current. B&W 800D series is current hungry
 

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Quote:
Funny thing about the passive/active biamp discussion is that most every speaker manufacturer recommends Passive biamping because that method still utilizes the speakers internal crossovers that their engineers spent quite a bit of time carefully designing to work with the given driver and enclosure package.

This statement alone shows that you really don't quite understand things as well as you think you do. And I am not saying this as a slam or a put down against you.


But bi-amping passively or actively takes advantage of only one thing and that is the same thing; the crossovers ability to be separated. Even if the crossover didn't have that capability, it is still designed the exact same way, the high frequencies get sent to the tweeter and the low frequencies get sent to the woofer. Nothing changes in that respect when bi-amping. This talk that the manufacturers "recommend" it is because the speaker has an additional set of binding posts that are way over priced and if they aren't 'suggested' to be used, the consumer would feel ripped off and return or not buy from that manufacturer again.
 

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Quote:
Originally Posted by Splicer010 /forum/post/18175805


This statement alone shows that you really don't quite understand things as well as you think you do. And I am not saying this as a slam or a put down against you.


But bi-amping passively or actively takes advantage of only one thing and that is the same thing; the crossovers ability to be separated. Even if the crossover didn't have that capability, it is still designed the exact same way, the high frequencies get sent to the tweeter and the low frequencies get sent to the woofer. Nothing changes in that respect when bi-amping. This talk that the manufacturers "recommend" it is because the speaker has an additional set of binding posts that are way over priced and if they aren't 'suggested' to be used, the consumer would feel ripped off and return or not buy from that manufacturer again.


Does Bi-Amping bring you more current
 

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I run Tri-amp config (Passive) 3 identical sterio amps= 6 amps..


Some of the realy highend speakers around such as the B&W 4way trailblazing Nautilus run Active using digital X overs, Active can/does have A few advantages over Passive (using internal Xover)..


With true Active method the Xovers are placed inbetween the Preamp and

Power amps So the Power amps only see's the exact (now isolated) frequency's required by that Driver(s) xover, providing much improved Dynamics and damping factor as opposed to A power amp receiving the full bandwidth in Passive config..


Also Digital Xovers have the advantage of much Greater precision compared to Analog crossover filters, but ant getting into that now instead read this..

http://sound.westhost.com/biamp-vs-passive.htm

http://www.bowers-wilkins.com/display.aspx?infid=1729


Cheers...
 

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Quote:
Originally Posted by wse /forum/post/18175790


Yes I agree Bi-wiring just looks good, I guess the big advantage of Bi-amping is providing more current. B&W 800D series is current hungry

That depends on what you are comparing it to. Compare the biamp setup to a mono amp with equivalent power to the pair. More current is available to the woofers, where the most current is needed.
 

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Quote:
Originally Posted by wse /forum/post/18175834


Does Bi-Amping bring you more current

I think that's an ambiguous question.


Speakers demand no more current than dictated by ohm's law. So there's no need for more current if your amp produced sufficient output. Where current matters is when you try to use 4 ohm speakers with an amp/receiver not designed for it. The amp/receiver will either shut down, current limit or the rail voltage will drop. An amp with better low impedance capability with fare better. This has nothing to do with biamping, IMO.


So we are really talking about whether biamping gives you sufficient power vs. not biamping. And that question is pointless. Because it depends on the amps in question.


Two 100 watt amps being used to biamp will be better than one 25 watt amp, for example. But one 1000 watt amp will be better than two 50 watt amps.
 

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Quote:
Originally Posted by Splicer010 /forum/post/18175805


This statement alone shows that you really don't quite understand things as well as you think you do. And I am not saying this as a slam or a put down against you.


But bi-amping passively or actively takes advantage of only one thing and that is the same thing; the crossovers ability to be separated. Even if the crossover didn't have that capability, it is still designed the exact same way, the high frequencies get sent to the tweeter and the low frequencies get sent to the woofer. Nothing changes in that respect when bi-amping. This talk that the manufacturers "recommend" it is because the speaker has an additional set of binding posts that are way over priced and if they aren't 'suggested' to be used, the consumer would feel ripped off and return or not buy from that manufacturer again.

Maybe so, and I'm sure plenty of other people don't as well. Maybe I wasn't clear enough for you to understand what I meant. Quite a few speaker manufacturers that build biamp capable speakers recommend that IF you utilize that OPTIONAL feature, only passive biamp and utilize the existing crossovers as oppose to removal/bypassing of those crossovers and active biamping. I've read that in several owner's manuals and also on the speaker company's websites.
 

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Quote:
Originally Posted by penngray /forum/post/18175656


lol, more efficiently???


Is that like asking if some speaker wires make the notes lighter and they just jump



Which stick to science if we are going to discuss it all and leave the subjective banter to audiofools

All I was trying to say is that if a speaker cable manufacturer has a certain cable design and CLAIMS that it does something amazing-Who has ever actually tested and confirmed that the claims were totally false other than saying something like " the speaker sounded no different with the X15 cable than it did with a common coat hanger" I don't buy into all the fluff either, however I don't see what's wrong with buying something that you think is cool for whatever reason and feeling like your system improved in some way when you use it.
 

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If someone can afford to risk throwing away money, fine with me. I wish they would let me sell them a cryogenically treated audiophile cable though (which I bought for $5, put in my freezer, and sold for $100.)
 

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Why do I feel like I'm the only person here that's not using 16 gauge lamp cord from Home Depot?
 
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