Can biamping blow my speakers?

[bandphan]

As for me, I was more asking about the true benefit of bi-wiring.

none at all

 

[Lordoftherings]

Back-EMF and Bi-Wiring.

Bi-wiring improves clarity in loud passages by preventing the back EMF (electro-mechanical feedback) that is inevitably generated by the woofers from getting into and saturating the crossover for the mid and high drivers; it's only path is to go all the way back to the amplifier's speaker terminals and back down the other cables, which it cannot do against the electron flow from the amplifier in a bi-wired system.

So, again, TLS Guy and also Bandphan, my question is: Is Bi-Wiring has any benefit at all?

Bob

 

[Lordoftherings]

No benefit, and it doubles the risk of a wiring error!

Hmmm...

none at all

Hmmm...






You or me?

 

[bandphan]

Bi-wiring improves clarity in loud passages by preventing the back EMF (electro-mechanical feedback) that is inevitably generated by the woofers from getting into and saturating the crossover for the mid and high drivers; it's only path is to go all the way back to the amplifier's speaker terminals and back down the other cables, which it cannot do against the electron flow from the amplifier in a bi-wired system.

So, again, TLS Guy and also Bandphan, my question is: Is Bi-Wiring has any benefit at all?

Bob

1 wire> divided into 4 leads>into 1 passive crossover = nothing. Take the terminal off the back of your speaker and look at the wiring. Regardless if you use the jumpers or the "bi wires" the resullt is the same.

 

[Lordoftherings]

EMF Electric & Magnetic Fields

* http://www.freepatentsonline.com/6870934.html

* http://en.allexperts.com/q/Home-Theater-2859/Speaker-impedance.htm



* http://www.metacafe.com/watch/861016/emf_electro_magnetic_field_from_speakers/

Just to add some interesting facts.

 

[Lordoftherings]

1 wire> divided into 4 leads>into 1 passive crossover = nothing. Take the terminal off the back of your speaker and look at the wiring. Regardless if you use the jumpers or the "bi wires" the resullt is the same.

Did you just read my post? Please do reread it very carefully before making any premature judgement.

 

[TLS Guy]

Bi-wiring improves clarity in loud passages by preventing the back EMF (electro-mechanical feedback) that is inevitably generated by the woofers from getting into and saturating the crossover for the mid and high drivers; it's only path is to go all the way back to the amplifier's speaker terminals and back down the other cables, which it cannot do against the electron flow from the amplifier in a bi-wired system.

So, again, TLS Guy and also Bandphan, my question is: Is Bi-Wiring has any benefit at all?

Bob

That is nonsense. Most passive crossovers pretty much eliminate the back EMF of a speaker reaching the terminals and therefore make the issue of the damping factor of an amp mute. When you bi wire you just have increased the resistance of the jumper slightly, nothing else. Bi wiring is 100% bogus and has no benefit what ever. Even is back EMF were an issue which it isn't, bi wiring would not change the equation.

In an active system, with the woofer directly connected by a wire of low resistance to an amp with decent damping factor, does keep the woofer under better control, slightly.

 

[Lordoftherings]

Benefits of bi-wiring > Provides full isolation from back EMF.

That is nonsense. Most passive crossovers pretty much eliminate the back EMF of a speaker reaching the terminals and therefore make the issue of the damping factor of an amp mute. When you bi wire you just have increased the resistance of the jumper slightly, nothing else. Bi wiring is 100% bogus and has no benefit what ever. Even is back EMF were an issue which it isn't, bi wiring would not change the equation.

In an active system, with the woofer directly connected by a wire of low resistance to an amp with decent damping factor, does keep the woofer under better control, slightly.

"That is nonsense"!!!

Thanks for the kind words. I appreciate the positive feedback.

I should, however, clarify some of what I may not have explained correctly when I was talking about the subject with you.
Bi-wiring is an advantage due to the finite resistance of speaker cable, which is likely to be in the range of 10-100 times the output impedance of the power amplifier. This cable resistance can allow distortion products to appear on the cable, and enter other drivers in the speaker.
The reason this happens is that the impedance of a speaker voice coil is not linear. Distortion products which appear in the motion of the driver will, through back EMF (ElectroMotive Force), modulate any resistance which is present at the source. If those distortion products lie above the crossover frequency, they will become signals which can be reproduced by other drivers in the same box.
Bi-wiring more effectively blocks these distortion signals by placing the low resistance of the amplifier between the woofer, for instance, and the input terminals of the midrange. This is a relatively subtle effect, but may be of interest in a refined system.

Sincerely,

Bob

Note: After having bi-wired their speakers, some people immediately noticed a much cleaner midrange and wider apparent dynamic range, especially in music with extended high-level bass.
And one does not have to use heavy-gauge cable for the midrange/tweeter section of the speaker. For the bass, a heavier gauge is preferable, of course.
The longer your speaker cable runs, the more important bi-wiring becomes.

 

[Lordoftherings]

This is not some Hocus-Pocus type of illusion.

* Bi-wiring at its best keeps back "emf" from the woofer out of the tweeter circuit, and can increase clarity by reducing this distortion. We may find the the improvement somewhat subtle, but cumulatively resulting in better listening to more effortless sound.*

You are very welcome to disagree with this statement, but to call it "nonsense", is indeed nonsense.

Regards,

Bob

 

[mtrycrafts]

Forgive the basic question but I am really baffled.

My setup:
I have a pair of KEF iQ9 speakers(rated 20 to 150 Ohm) and an Onkyo SR-607(7channel x 90 watts). Both speakers and amp are capable of biamping...

My question/problem:
If I biamp my speakers I am supplying 90x2 watts to each speakers...could it burn my speakers if I turn up the volume, since I am sending more power than the could endure? The question I am asking is it almost already happened..After I hooked them, immediately noticed that one of the tweeters on a speaker has gone silent..it simply didn't produce any sound above 2000 Hz. I RMAd that one and tomorrow I am getting the replacement. I don't want to burn this one with bi-amping! So please help!!

Thanks,
Damon

Did you remove the shorting strap at the speakers?

 

[TLS Guy]

"That is nonsense"!!!

Thanks for the kind words. I appreciate the positive feedback.

I should, however, clarify some of what I may not have explained correctly when I was talking about the subject with you.
Bi-wiring is an advantage due to the finite resistance of speaker cable, which is likely to be in the range of 10-100 times the output impedance of the power amplifier. This cable resistance can allow distortion products to appear on the cable, and enter other drivers in the speaker.
The reason this happens is that the impedance of a speaker voice coil is not linear. Distortion products which appear in the motion of the driver will, through back EMF (ElectroMotive Force), modulate any resistance which is present at the source. If those distortion products lie above the crossover frequency, they will become signals which can be reproduced by other drivers in the same box.
Bi-wiring more effectively blocks these distortion signals by placing the low resistance of the amplifier between the woofer, for instance, and the input terminals of the midrange. This is a relatively subtle effect, but may be of interest in a refined system.

Sincerely,

Bob

Note: After having bi-wired their speakers, some people immediately noticed a much cleaner midrange and wider apparent dynamic range, especially in music with extended high-level bass.
And one does not have to use heavy-gauge cable for the midrange/tweeter section of the speaker. For the bass, a heavier gauge is preferable, of course.
The longer your speaker cable runs, the more important bi-wiring becomes.

Please give scientific reference that speaker cables cause distortion. At worst a speaker cable adds resistance which can change the Q of the bass speaker alignment.

The series inductor/inductors of the low pass crossover will severely limit back EMF from a woofer. This is the only driver where this is only an issue. However in an amp with low source resistance and high slew rate, back EMF will help control the woofer overhang in an active biamped system. Passive crossovers pretty much negate this.

Bi wiring is nothing more than a long high resistance shunt bar. The onus is on you to show how this is not so. If you think about it, it is no different than having the jumpers have the same resistance as the added speaker cable.

Any other theories are just extrapolating beyond the facts.

 

[Loren42]

Forgive the basic question but I am really baffled.

My setup:
I have a pair of KEF iQ9 speakers(rated 20 to 150 Ohm) and an Onkyo SR-607(7channel x 90 watts). Both speakers and amp are capable of biamping...

My question/problem:
If I biamp my speakers I am supplying 90x2 watts to each speakers...could it burn my speakers if I turn up the volume, since I am sending more power than the could endure? The question I am asking is it almost already happened..After I hooked them, immediately noticed that one of the tweeters on a speaker has gone silent..it simply didn't produce any sound above 2000 Hz. I RMAd that one and tomorrow I am getting the replacement. I don't want to burn this one with bi-amping! So please help!!

Thanks,
Damon

AS others have pointed out, bi-amping will not over power your speakers.

As for the blown tweeter, do you have a capacitor in-line with the tweeter?

If not, you should put a 50 µf non-polarized cap in line of the tweeter. This acts as a DC block to protect the tweeter.

When you first turn on an amp you may get a pop, which could blow the tweeter. A passive crossover would normally block that, but an active system has no protection unless you put one in there.

Also, it is good practice to turn on the power amp last when turning everything on and make the power amp the first thing you turn off when you shut it down.

I think the bi-wiring argument is already well represented, so I won't jump into that mess.

 

[TLS Guy]

AS others have pointed out, bi-amping will not over power your speakers.

As for the blown tweeter, do you have a capacitor in-line with the tweeter?

If not, you should put a 50 µf non-polarized cap in line of the tweeter. This acts as a DC block to protect the tweeter.

When you first turn on an amp you may get a pop, which could blow the tweeter. A passive crossover would normally block that, but an active system has no protection unless you put one in there.

Also, it is good practice to turn on the power amp last when turning everything on and make the power amp the first thing you turn off when you shut it down.

I think the bi-wiring argument is already well represented, so I won't jump into that mess.

There already will be a cap or caps in series with the tweeter in the high pass filter of the crossover, so he won't need another one, like you would need the 50 mfd cap with an active crossover. In the latter case the amp would be directly connected to the speaker without the addition of a cap.

The more I think about this, the more I fell it is likely he clipped the amp as he thought he could play it louder. It is not generally realized that an amp clips easily when producing no or little power, as it is easy to exceed the demands of the voltage of the power supply. In fact into an eight ohm load, the clip point would be pretty much identical whether the amp was delivering power to a load or not.

 

[Loren42]

There already will be a cap or caps in series with the tweeter in the high pass filter of the crossover, so he won't need another one, like you would need the 50 mfd cap with an active crossover. In the latter case the amp would be directly connected to the speaker without the addition of a cap.

The more I think about this, the more I fell it is likely he clipped the amp as he thought he could play it louder. It is not generally realized that an amp clips easily when producing no or little power, as it is easy to exceed the demands of the voltage of the power supply. In fact into an eight ohm load, the clip point would be pretty much identical whether the amp was delivering power to a load or not.

Maybe I misunderstood the poster's question. I thought he had already bi-amped and lost a tweeter.

I would have assumed that he would have bypassed or removed the passive crossover when bi-amping. Maybe not? I do not know anything about the KEF speakers.

 

[TLS Guy]

Maybe I misunderstood the poster's question. I thought he had already bi-amped and lost a tweeter.

I would have assumed that he would have bypassed or removed the passive crossover when bi-amping. Maybe not? I do not know anything about the KEF speakers.

The OP was passive biamping. He took off the strap between the high and low pass filters. Both amps are reproducing the same full range signal, and the amps are connected to the passive low and high pass filters respectively. A really pointless exercise and with some degree of hazard.

 

[R-Carpenter]

Could it be that the crossover really has 2 outputs on the outside of the speaker and goes to the same terminal inside? I think it's known as a fake bi wire or bi amp. If so, there's a possibility of generating a strong DC pulse and blowing a tweeter. I'd start with puling out the crossover and posting pictures. It could also be a wire fallen off or burned.

 

[mtrycrafts]

Could it be that the crossover really has 2 outputs on the outside of the speaker and goes to the same terminal inside? I think it's known as a fake bi wire or bi amp. If so, there's a possibility of generating a strong DC pulse and blowing a tweeter. I'd start with puling out the crossover and posting pictures. It could also be a wire fallen off or burned.

I would think if that is the case, the company is committing fraud.

 

[R-Carpenter]

Not necessarily. If 2 of your amps, used for bi-amping have exactly the same output and magically matched output devises, then you would be amplifying 1 speaker with 2 amps. I don't know for sure and it's just an uneducated guess but I remember seeing crossovers with the external jumpers on terminals but joining inside to the same.
Pull out the crossovers, let's see.