Question on bi-amping - Page 2 - AVS Forum | Home Theater Discussions And Reviews
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post #31 of 1069 Old 09-27-2013, 12:06 PM
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Originally Posted by DonH50 View Post

.......I hesitate to bring it up, but there are potential theoretical benefits from passive bi-amping due to lower power demands. I cannot imagine audible benefits, however, for any reasonable system........

Yes, that's quite true. There is mathematical proof that even passive bi-amping can have an effect on the reproduced signal. It has to do with the way the speaker wire reacts with the load of the crossover. Of course the links must be off at the speakers. It can probably even be measured. But you are also quite correct in that the effect is so miniscule it would never he heard nor does it warrant any discussion in a real world system.

On a practical level a proper bi-amped system uses a line level crossover. Anything else is just audiophile folklore.

P.S. I run biamped LCR using a Behringer 2496 - great unit. My mid amps are DIY 70W tube KT88 PP and my tweeters are 10w 6V6PP maps. My subs are off a rebuilt Phase Linear 700.

And no, tubes are not better than transistors. I just like the old stuff wink.gif
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post #32 of 1069 Old 09-27-2013, 12:20 PM
 
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Originally Posted by kbarnes701 
They know exactly what they are doing. They know that there are many uninformed and ignorant customers in the world and even more who don't have the faintest understanding of physics, electronics or acoustics. Because of the general lack of understanding of the science behind AV, many unscrupulous manufacturers have sprung up to take advantage of this lack of understanding - they sell 'snake oil' products like $1,000 interconnects, cable supports, little 'beaks' to stick on your speakers and so on and on. All of this puts Rotel in a difficult position. They know that there are huge numbers of people who fall for all this audio nonsense. If they follow their own serious engineering beliefs and principles, they ignore rubbish like passive bi-amping. But then they lose out on sales to the people who believe in these audio fairies. So, to protect their commercial interests, they add these useless features. It costs them very little and is certainly better than losing large numbers of sales. They know the gimmicks don't do anything useful of course - but they have to sell product or they go out of business, and AV is a very competitive market.

All my life has been spent in advertising and marketing. I have had this sort of discussion more than once with manufacturers who implement pointless product features in order to maintai na competitive advantage in a marketplace which is largely ruled by ignorance. My advice to you: try to learn some of the science and don't be so easily taken in by marketing.

Did you take a look at the schematic?
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post #33 of 1069 Old 09-27-2013, 12:37 PM
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Originally Posted by DonH50 View Post

- If you have a 100 W amp applied to the bass and treble you get 100 W and that is the maximum seen by either frequency band.

- If you use two 100 W amps the bass sees 100 W and the treble sees 100 W. There can be headroom benefits with an active crossover but the max power each frequency band sees is still just 100 W.

I am aiming to go to active crossover and bi-amping eventually with my speakers and have been on the lookout for moderately priced suitable amps. I figured they didn't need to be huge expensive powerhouses for the project.

So recently got myself a single Nuforce STA-100 80w 2ch amp for a trial. When playing my music loud, some tracks that had large dynamic swings did cause the amp to shut down into protection mode from too much current being demanded from it.

Apart from that it performed fine so I went ahead and purchase a second one and at the moment are running them 'vertical' passively bi-amped. (one amp for each speaker rather than one amp for the highs and one for the lows) I have not had them shut down into protection mode since.

I do know for a full range signal/speaker that the halfway point for power demand is around 300hz. So yes typically a full range speaker with a 2.3khz crossover is going to be wasting a lot of power in one of those amp channels. My speakers however are 2-ways with a crossover at 1000hz and with bass management taking 80hz and below off them. I would imagine that would put my halfway point for power demand somewhere closer to the 1000hz crossover?

4 channels of 80w has got to be better than 2 channels of 80w.. ?

..
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post #34 of 1069 Old 09-27-2013, 12:43 PM
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Originally Posted by FMW View Post
 
Quote:
Originally Posted by kbarnes701 View Post


All my life has been spent in advertising and marketing. I have had this sort of discussion more than once with manufacturers who implement pointless product features in order to maintai na competitive advantage in a marketplace which is largely ruled by ignorance. My advice to you: try to learn some of the science and don't be so easily taken in by marketing.

One of my favorites is the difference between contact lenses that need to be changed daily and those that can be worn all week. The difference is nothing but the warranty and the marketing. The business world is full of these kinds of things. Using pseudo science as a sales tool is very common. Just look at any ad for anything sold in a health food store or any orally taken product designed to help you lose weight.

 

Yup. The diet industry is an especially bad/good example - it is a multi-billion dollar industry based on the premise that their products are specifically designed NOT to work, in order to generate repeat business for ever. The misinformation in that sector rivals, and maybe even exceeds, the misinformation targeted at the 'audiophiles'. 

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post #35 of 1069 Old 09-27-2013, 12:45 PM
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Originally Posted by Heinrich S View Post
 
Quote:
Originally Posted by kbarnes701 
They know exactly what they are doing. They know that there are many uninformed and ignorant customers in the world and even more who don't have the faintest understanding of physics, electronics or acoustics. Because of the general lack of understanding of the science behind AV, many unscrupulous manufacturers have sprung up to take advantage of this lack of understanding - they sell 'snake oil' products like $1,000 interconnects, cable supports, little 'beaks' to stick on your speakers and so on and on. All of this puts Rotel in a difficult position. They know that there are huge numbers of people who fall for all this audio nonsense. If they follow their own serious engineering beliefs and principles, they ignore rubbish like passive bi-amping. But then they lose out on sales to the people who believe in these audio fairies. So, to protect their commercial interests, they add these useless features. It costs them very little and is certainly better than losing large numbers of sales. They know the gimmicks don't do anything useful of course - but they have to sell product or they go out of business, and AV is a very competitive market.

All my life has been spent in advertising and marketing. I have had this sort of discussion more than once with manufacturers who implement pointless product features in order to maintai na competitive advantage in a marketplace which is largely ruled by ignorance. My advice to you: try to learn some of the science and don't be so easily taken in by marketing.

Did you take a look at the schematic?

 

What would be the purpose of that?  Biamping requires electronic (active) crossovers between the pre and power amps and the removal of the passive crossovers in the speakers. Are you going to remove the passive crossovers from your speakers?  No?  Then you are wasting an amp, some wire and your time.

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post #36 of 1069 Old 09-27-2013, 12:57 PM
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Thanks for the kind comments on my post!

Regarding the power demands, one thing you can do to get a better feel for the sound is to look up equal loudness curves (Fletcher-Munson, derived from earlier work, is a good starting point) and see how we perceive loudness vs. frequency and level. Depending on the volume and crossover point, the power ratio between highs and lows can be 10x (10 dB), 100x (20 dB), or more. Of course, the high end rises a bit too, but most of us roll it off in the system or our ears.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #37 of 1069 Old 09-27-2013, 02:19 PM
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Originally Posted by kiwi2 View Post



4 channels of 80w has got to be better than 2 channels of 80w.. ?

..

Only if you use more than 80 watts.
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post #38 of 1069 Old 09-27-2013, 02:24 PM
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Originally Posted by FMW View Post

Only if you use more than 80 watts.

Well considering one amp by itself was shutting down into protection mode... I must have been.
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post #39 of 1069 Old 09-27-2013, 05:20 PM
 
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Originally Posted by DonH50 View Post

- If you have a 100 W amp applied to the bass and treble you get 100 W and that is the maximum seen by either frequency band.

Lets turn this into a real world example. 100 watts into 8 ohms is 28 volts. So your power amp is putting out about 28 volts @ 100 watts.
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- If you use two 100 W amps the bass sees 100 W and the treble sees 100 W.

Since there is no crossover routing signals in different frequency ranges to the power amps, each power amp is still putting out 28 volts.

The tweeter and the woofer each see 28 volts just like they did with 1 power amp. The total power that is delivered to the speaker remains the same.
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There can be headroom benefits with an active crossover but the max power each frequency band sees is still just 100 W. There is no more voltage to be had from the amps, you don't get 200 W to anything. Using passive bi-amping as implemented by the vast majority of AVRs there's not even a significant increase in headroom because both amplifiers still see the entire signal band.

Exactly.
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- If you really want to play louder, get a bigger amp.

Or, go for an active crossover.

If you have an active crossover the signals at various frequencies are routed to one amp or the other. The amps have lower input voltages so all things being equal, they have lower output voltages. You then actually have more headroom.
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post #40 of 1069 Old 09-27-2013, 05:23 PM
 
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Originally Posted by kiwi2 View Post

Quote:
Originally Posted by FMW View Post

Only if you use more than 80 watts.

Well considering one amp by itself was shutting down into protection mode... I must have been.

Or not. There are many reasons for an amp to shut itself down, such as shorted speaker cables.

Sometimes just a few strands going where they don't belong can make an amp shut down,

Heat is another reason for shutdowns.

The amps I've had that would shut down for those kinds of faults would not shut down for simple clipping.
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post #41 of 1069 Old 09-27-2013, 05:43 PM
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Originally Posted by arnyk View Post

Or not. There are many reasons for an amp to shut itself down, such as shorted speaker cables.

Sometimes just a few strands going where they don't belong can make an amp shut down,

Heat is another reason for shutdowns.

The amps I've had that would shut down for those kinds of faults would not shut down for simple clipping.

The STA-100 is a D-class amp with feedback circuitry. The salesman who sold me it (who has been selling NuForce products for many years) said that if you overdrive them they will just shut themselves off for a few seconds. That's exactly what I experienced when I had just one amp driving both speakers very loud on certain tracks. Would happen a couple of times per night perhaps. Haven't triggered them off since getting the second one though.
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post #42 of 1069 Old 09-27-2013, 05:46 PM
 
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Originally Posted by Heinrich S View Post

[

Did you take a look at the schematic?

Yes. It is absolutely standard passive biamping nonsense.
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post #43 of 1069 Old 09-27-2013, 08:07 PM
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You guys sure have a short Heinrich S memory. Carried on for several pages in another old thread presenting himself as a stereotypical "true believer" audiophile, then near the end after wasting the time of many people who took his bait, he claimed it was all just a ruse, that he was merely taking on a role and only pretending to believe in the usual litany of audio nonsense. Fool me once...

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Isn't it obvious I was trolling you before? What do you think I really believe? Present your questions and I will gladly answer them for you.
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Originally Posted by Heinrich S View Post

I must apologise for my behaviour. I was asked to assume the position of a charlatan as part of a case study on human behaviour. The worst is over now. smile.gif

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Exactly, I was so convinced their position was true that I pretended to be a zealot regurgitating the same tired arguments like a parrot and in the process tried to get them to spin their wheels. Asking them to independently verify the verified results clearly got their panties in a knot! biggrin.gif

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Originally Posted by Heinrich S View Post

I commend you for defending our position so rigorously. The bigot comment was not part of any act - we are all bigots to some degree.

Most of us are fanatics at heart, trying to convince the other side to believe our own truth - our own cause - just like the charlatans do, except they promote mysticism and the unknown in order to fuel their disbelief.

I'm afraid no one is going to truly convince a bigot to change his position.

And in reply to a question posed to him about what he really thought about amplifiers subsequent to admitting to his long run of disingenuous posting behavior, he stated:
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Originally Posted by Heinrich S View Post

Amplifiers don't make much of a difference unless they have a high source impedance, are driven into gross distortion or are used at different volume levels. So, in other words, I agree with the DBT method and the protocols discussed so far. However to my knowledge there is no universally accepted DBT protocols used in audio. Perhaps I'm wrong on that.
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post #44 of 1069 Old 09-28-2013, 01:06 AM
 
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Originally Posted by arnyk 
Since there is no crossover routing signals in different frequency ranges to the power amps, each power amp is still putting out 28 volts.

The tweeter and the woofer each see 28 volts just like they did with 1 power amp. The total power that is delivered to the speaker remains the same.

From the article you cited on page 1 :

"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."

So I would be using more power using 2 x stereo 60 watt amplifiers. You guys were saying that the power would remain the same = 2 x 60 watts, not 2x 120 watts. The author you cited is contradicting the comments in this thread.
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post #45 of 1069 Old 09-28-2013, 04:55 AM - Thread Starter
 
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Originally Posted by arnyk 
Since there is no crossover routing signals in different frequency ranges to the power amps, each power amp is still putting out 28 volts.

The tweeter and the woofer each see 28 volts just like they did with 1 power amp. The total power that is delivered to the speaker remains the same.

Please correct me if I'm wrong here, but if I'm understanding things correctly here, passive bi-amplification which drives the highs and lows with the same full range signal is no different whether it is 1 amplifier delivering the full range signal or whether it is two amps driving the same full range signal.

Am I understanding this correctly?

Bi-amplification, in the true sense of the word, would be driving the highs and lows independently with an active crossover. Do I have this all correct? Only thing I don't understand is the power issue. As Heinrich S mentioned, if you're using 2 x 100 watt stereo amps in bi-amp mode (passive), would the power still be 100 watts per channel or would there be more power?

I took a look at that article you posted and it mentioned that power would double. confused.gif Obviously I'm a little confused at this point. Thanks again for your contributions so far in this thread. That goes to everyone who has posted! Thanks.
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post #46 of 1069 Old 09-28-2013, 06:26 AM
 
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Originally Posted by OllieS View Post

Quote:
Originally Posted by arnyk 
Since there is no crossover routing signals in different frequency ranges to the power amps, each power amp is still putting out 28 volts.

The tweeter and the woofer each see 28 volts just like they did with 1 power amp. The total power that is delivered to the speaker remains the same.

Please correct me if I'm wrong here, but if I'm understanding things correctly here, passive bi-amplification which drives the highs and lows with the same full range signal is no different whether it is 1 amplifier delivering the full range signal or whether it is two amps driving the same full range signal.

You are right as rain.
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Bi-amplification, in the true sense of the word, would be driving the highs and lows independently with an active crossover. Do I have this all correct?

You are again right as rain.
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Only thing I don't understand is the power issue. As Heinrich S mentioned, if you're using 2 x 100 watt stereo amps in bi-amp mode (passive), would the power still be 100 watts per channel or would there be more power?

There will be no more power delivered to the speakers.
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I took a look at that article you posted and it mentioned that power would double. confused.gif Obviously I'm a little confused at this point. Thanks again for your contributions so far in this thread. That goes to everyone who has posted! Thanks.

I must of screwed up because I thought I reviewed that article to ensure that it did not repeat the "doubled power" myth.
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post #47 of 1069 Old 09-28-2013, 06:32 AM
 
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Originally Posted by kiwi2 View Post

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Originally Posted by arnyk View Post

Or not. There are many reasons for an amp to shut itself down, such as shorted speaker cables.

Sometimes just a few strands going where they don't belong can make an amp shut down,

Heat is another reason for shutdowns.

The amps I've had that would shut down for those kinds of faults would not shut down for simple clipping.

The STA-100 is a D-class amp with feedback circuitry. The salesman who sold me it (who has been selling NuForce products for many years) said that if you overdrive them they will just shut themselves off for a few seconds.

That sort of behavior is generally considered to be a no-no for a well-designed amp. A good amp has very fast recovery (milcroseconds) from being overdriven.

Your story frustrates me because I feel like you were scammed by overpaying for amplifiers that are outperformed by amps at a fraction of the price. Let's face it, you don't need a DBT to know that an amp that shuts down for a few seconds when you overdrive it!
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That's exactly what I experienced when I had just one amp driving both speakers very loud on certain tracks. Would happen a couple of times per night perhaps. Haven't triggered them off since getting the second one though.

There is a basic rule of science and that is that you don't make global rules based on pathological equipment. The Nuforce is IMO behaving like pathological equipment. That should be the end of the discussion of your Nuforce amp. It appears to be very substandard. It has an audible flaw that thousands of makes and models of amp have avoided for decades. I am very sorry that you have been cursed with it.
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post #48 of 1069 Old 09-28-2013, 06:42 AM
 
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Quote:
Originally Posted by Heinrich S View Post

Quote:
Originally Posted by arnyk 
Since there is no crossover routing signals in different frequency ranges to the power amps, each power amp is still putting out 28 volts.

The tweeter and the woofer each see 28 volts just like they did with 1 power amp. The total power that is delivered to the speaker remains the same.

From the article you cited on page 1 :

"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."

So I would be using more power using 2 x stereo 60 watt amplifiers. You guys were saying that the power would remain the same = 2 x 60 watts, not 2x 120 watts. The author you cited is contradicting the comments in this thread.

They slipped one by me. This statement is true:

"The system's total amplifier power has been doubled,"

That's obvious, but we have to remember that amplifier power represents a possibility of providing more power to the speakers, not necessarily the accomplishment of such a thing. Using an overpowered amp is the same thing - you can have a 4 Kw amplifier but that doesn't mean you are going to benefit from it, or even could possibly benefit from that extra power.

This is the false claim:

"which is probably a good thing and may actually result in a sonic improvement at high listening levels"

I apologize for providing a reference that so many found confusing.
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post #49 of 1069 Old 09-28-2013, 06:43 AM - Thread Starter
 
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Originally Posted by arnyk 
You are right as rain.

Thanks Arny! At least I'm learning something new today which for me is a rare thing. rolleyes.gif
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There will be no more power delivered to the speakers.

Apologies for stressing this point, but I would really appreciate it if you could explain to a simpleton like me why the power would not go up. I'm not arguing with you, I just don't understand this part of the discussion very well.
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post #50 of 1069 Old 09-28-2013, 06:51 AM
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Originally Posted by CruelInventions View Post

You guys sure have a short Heinrich S memory. Carried on for several pages in another old thread presenting himself as a stereotypical "true believer" audiophile, then near the end after wasting the time of many people who took his bait, he claimed it was all just a ruse, that he was merely taking on a role and only pretending to believe in the usual litany of audio nonsense. Fool me once...
 
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Originally Posted by Heinrich S View Post

Isn't it obvious I was trolling you before? What do you think I really believe? Present your questions and I will gladly answer them for you.
Quote:
Originally Posted by Heinrich S View Post

I must apologise for my behaviour. I was asked to assume the position of a charlatan as part of a case study on human behaviour. The worst is over now. smile.gif
 
Quote:
Originally Posted by Heinrich S View Post

Exactly, I was so convinced their position was true that I pretended to be a zealot regurgitating the same tired arguments like a parrot and in the process tried to get them to spin their wheels. Asking them to independently verify the verified results clearly got their panties in a knot! biggrin.gif
 
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Originally Posted by Heinrich S View Post

I commend you for defending our position so rigorously. The bigot comment was not part of any act - we are all bigots to some degree.

Most of us are fanatics at heart, trying to convince the other side to believe our own truth - our own cause - just like the charlatans do, except they promote mysticism and the unknown in order to fuel their disbelief.

I'm afraid no one is going to truly convince a bigot to change his position.

And in reply to a question posed to him about what he really thought about amplifiers subsequent to admitting to his long run of disingenuous posting behavior, he stated:
Quote:
Originally Posted by Heinrich S View Post

Amplifiers don't make much of a difference unless they have a high source impedance, are driven into gross distortion or are used at different volume levels. So, in other words, I agree with the DBT method and the protocols discussed so far. However to my knowledge there is no universally accepted DBT protocols used in audio. Perhaps I'm wrong on that.

 

Self-confessed troll then. The 'case study in human behaviour' that was used an excuse for his previous trolling must have been untrue. I doubt if he is on another 'case study in human behaviour'.

 

Best thing I can think of is to just ignore him then - that usually makes them give up pretty quick. Thanks for the heads-up BTW - I had entirely forgotten I had encountered this person before.

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post #51 of 1069 Old 09-28-2013, 07:05 AM
 
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Quote:
Originally Posted by arnyk 
You are right as rain.

Apologies for stressing this point, but I would really appreciate it if you could explain to a simpleton like me why the power would not go up. I'm not arguing with you, I just don't understand this part of the discussion very well.

This post does all that:

http://www.avsforum.com/t/1492314/question-on-bi-amping/30#post_23779193
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post #52 of 1069 Old 09-28-2013, 07:37 AM - Thread Starter
 
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Originally Posted by arnyk 
This post does all that:

It doesn't explain things clearly. If I have 2 x stereo amps at 100 watts per channel or 4 x 100 watts, you are saying that the power that the speaker "sees" is still 2 x 100 watts? I thought the total power doubled? confused.gif You even acknowledged that the power would double a few posts back.

So I'm confused here. With my hypothetical example do I gain double the power with two identical stereo amps, or not? I'm getting conflicting answers on this.
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post #53 of 1069 Old 09-28-2013, 07:58 AM
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Yes, if you biamplify and the amps you use are the same you will have double the power available. Arny's comment was that, if the original amp was adequate to the task, then adding more available power accomplishes nothing other than increasing the electric bill. If you use, say, 20 watts of the available 100 watts, then using 20 watts of 200 available watts is the same thing.
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post #54 of 1069 Old 09-28-2013, 08:55 AM - Thread Starter
 
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Yes, if you biamplify and the amps you use are the same you will have double the power available. Arny's comment was that, if the original amp was adequate to the task, then adding more available power accomplishes nothing other than increasing the electric bill. If you use, say, 20 watts of the available 100 watts, then using 20 watts of 200 available watts is the same thing.

Okay, that's what I wanted to know. This confused me :
Quote:
"I'm using 2 x Rotel rb970bx power amps and I'm bi-amping my speakers using the preouts on my receiver. Each power amp is 2 x 60 watts, so that I'm getting 120 watts per channel when bi-amping."
Quote:
Originally Posted by LTD02 
that's not correct.

the voltage from each amp is the same. the resistance from each portion of the crossover network is the same. as a result, even with two amps, power is the same.

So the right answer is that it *IS* correct, and you will get double the power.
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post #55 of 1069 Old 09-28-2013, 11:08 AM
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The confusion is around power and available power. Biamplifying doesn't cause the speakers to draw more power. They will behave the same with either setup. It simply increases the overhead. Passive biamplification doesn't gain you anything.
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post #56 of 1069 Old 09-28-2013, 11:26 AM - Thread Starter
 
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Originally Posted by FMW 
Biamplifying doesn't cause the speakers to draw more power. They will behave the same with either setup. It simply increases the overhead. Passive biamplification doesn't gain you anything.

So you are saying that the amount of current and voltage drawn from the amp will be the same going from 2 x 120 watt stereo amps in bi-amp mode vs 1 stereo 120 watt amp, but that there is more overall headroom available? I think I get what you're saying now.

The fact there is more power does not mean that power will be used.
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post #57 of 1069 Old 09-28-2013, 12:52 PM
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Take my experience with my 80w amps with my 2-way speakers. With the one 2ch amp, the left and right speaker had one channel each. The woofer and tweeter of each speaker had to share the same one 80w channel.

When I got the 2nd amp and went to bi-amping, the woofer now has its own 80w channel and the twetter has its own 80w channel. The thing to remember though is that lower frequencies demand more power than the higher frequencies. For example in a full range speaker if the woofer is drawing 50w then the tweeter may only be drawing 10w. So one amp channel will still be getting taxed quite heavily while the other channel is under utilised.

I mentioned in a previous post that the halfway point for power demand is roughly around 300hz with a full range speaker/signal. If however 80hz and below is being handled by subs and the speaker is only receiving 80hz and up, that halfway point for power demand is going to be a lot higher up the frequency range and closer to the 1khz crossover of my particular speakers. Thus better utilising both 80w channels.

Now I am only doing this because I eventually want to go to active crossovers for the speakers so I need 4 amp channels. Otherwise the speakers would have been better off with a single 160w 2ch amp.
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post #58 of 1069 Old 09-28-2013, 12:58 PM
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The fact there is more power does not mean that power will be used.
Bingo. The amount of power used depends on how sensitive your speakers are and how loud you want to play them. For a given loudness, you need X watts, and that's all your amp(s) will provide. Doesn't matter if it's one amp or 50.

Now, if your amp can't deliver X watts cleanly, then you have a problem. But the solution to that problem is to buy a bigger amp, not to buy a second small one.

If you can't explain how it works, you can't say it doesn't.—The High-End Creed

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post #59 of 1069 Old 09-29-2013, 02:36 AM - Thread Starter
 
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Thanks guys!!! Alright, I understand this a whole lot better now. So the only real benefit behind passive bi-amping is more available headroom, if you use two amplifiers which you could achieve with one bigger amplifier.

Now what are the benefits of active bi-amping? You can drive the highs and lows independently, but how does that benefit the system?
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post #60 of 1069 Old 09-29-2013, 04:41 AM
 
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Quote:
Originally Posted by OllieS View Post

Thanks guys!!! Alright, I understand this a whole lot better now.

Really? Why do you contradict accurate technical knowlege in your next line in your post?
Quote:
So the only real benefit behind passive bi-amping is more available headroom,

Read my lips. All other things being equal, there is no benefit.
Quote:
if you use two amplifiers which you could achieve with one bigger amplifier.

No, you can't achieve the benefits of a larger amplifier with passive biamping.
Quote:
Now what are the benefits of active bi-amping? You can drive the highs and lows independently, but how does that benefit the system?

It enables you to obtain more headroom at the cost of more amplifiers and an active crossover.
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