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hello everyone, is there any real improvment by bi-amp a speaker? currently I'm using Klipsch RF-35 speaker?
 

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This has been discussed ad nauseum. Do a search.


The general consensus is that if there's an audible difference, there must have been a deficiency in your original wires.
 

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Larry, he said "bi-amp" not "bi-wire".


There are clear advantages to bi-amping. The main one is, when an amp clips, it creates square waves with lots of high frequency info that wasn't in the original. Usually, a bass signal is what causes clipping. With a single amp, when the bass clips the amp, the resulting HF goes straight to the tweeter and sounds bad. Bi-amping, if the bass amp clips, none of the HF goes to the tweeter. Rather, it goes to the woofer's crossover where it gets filtered out. So, you get less "glare" when you play the music (too) loud.
 

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i read it somewhere that to turly bi-amp, I need to put in a active crossover between the preamp/precressor and the amp? arn't there already a crossover inside the speaker already?
 

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Yes, there are crossover circuits in most speakers. For the purists, to bi-amp the speakers requires bypassing the speakers' crossover circuits with external one. This is not easily done for most speakers.
 

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True, honest to gosh bi amping requires bypassing the internal passive x-over and using an external active x-over. The advantages are mostly control and higher efficiency.


So called passive bi amping is simply seperating the low frequencies from the highs electrically in the speaker, and using a seperate amp for each section. It has a similar cost compared to biamping, but the results are not as great, and can be almost nil in some cases.


Do a search here, and on the www. There is a tremendous amount of info about this.


Here's a place to start:

http://sound.westhost.com/bi-amp.htm


Keep in mind that this is not an easy thing to undertake.
 

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Replacing a speaker's internal passive crossover components with an outboard active crossover, will totally change the speaker's sound, regardless if you match the crossover slopes, levels, etc. The designer did things for a reason when designing/choosing the passive crossover topology, and the brands of components ( resisitors, capacitors, inductors wire, etc ) used to build it.


Bi-amping involves 2 amps per speaker, and 2 speaker cables per speaker ... which all costs money.

An alternate view is to just buy a better amp and speaker cables, and NOT bi-amp.


- Andy
 

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Quote:
Originally posted by Andy Lammer
Bi-amping involves 2 amps per speaker, and 2 speaker cables per speaker ... which all costs money.

An alternate view is to just buy a better amp and speaker cables, and NOT bi-amp.


- Andy
The extra cost of speaker & RCE cables required to change from single to bi-amp mode is not that expensive- not unless you're into exotic cables. £20 for another RCA pair, £20 for speaker cable.


I don't agree with with selling off the existing integrated then purchasing a new amp. Purchasing the matching 2 channel poweramp second hand a few years after you've bought the integrated amp can be a good upgrade.


If the integrated is a high quality model (a good pre-amp stage) then I would go down the biamp route.

I managed to buy the matching amp for £350, over half price. So that's £1000 spent on my integrated/poweramp. I don't know of any integrated's around this value that can outperform my system.


Although if the OP has a budget interated (ie bottom of the range Rotel with pre-outs) I would not buy the matching amp- most likely sell that and get a better performing integrated.
 

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I was considering Tri\\Vertical-Amping my speakers awhile ago and saved some post about the subject which is what follows. I am Bi-Amping my 3-ways using a Panasonic SA-XR45 right now.


Good luck!

=====================


3 types of Amping

Horizontal

Vertical

Bi-Amping


Horizontal--2way speakers

Is sharing the amps between both channels

You have 2 amps to share to drive the Tweeters and Woofers

1 amp to the Mid\\Tweeters for both Channels

1 amp to drive the Woofers for Both Channels


Horizontal for 3ways

You could have the tweeters,Mids and woofers being driven by 1 amp in both channels for sets of drivers it would still mean you are Horizontaly driving the speakers,but most speakers only come with 2 sets of binding post and do not allow to adjust levels so you are either have Horizontaly or Bi-amping capability.


Vertical Amping

Is usually done with an outboard XO which has many advantages ehich I will get to.Heres how it is setup.

For 3-ways speaker systems you'd need 3 sets of Monoblocks.

1 amp for each driver therefore you have 1 amp for each individual driver.They are looped between the driver to the outboard XO the XO is hooked into the L\\R Inputs of the preamp.

1-amp L. Ch. Tweeter Driver

1-amp R. Ch. Tweeter Driver

1-amp L. Ch. Midrange Driver

1-amp R. Ch. Midrange Driver

1-amp L. Ch. Woofer Driver

1-amp R. Ch. Woofer Driver


Hench you have dedicated amps for each driver.The Benefits of this are as follows:

Less Crosstalk

Less Distortion

More Efficientcy for amps to drive the speakers

Ability to adjust output levels of the Drivers using an ACTIVE CROSSOVER(usually outboard) which allows for better speaker to room interaction.


Just to follow that up .It usually takes an ACTIVE OUTBOARD XO to get Vertical amping.Some speaker manfs. do have internal ACTIVE XO's I think.


Active Crossovers are prefered because you can adjust levels and you would have to have the capability to adjust levels using different amps.



Bi-Amping has no value other than more power.



I hope that explains it! 8)


Here are examples of Crossovers
http://www.marchandelec.com/
http://www.bryston.ca/crossel.html


If I may, bi-amping doesn't really boost power that much, and it certainly doesn't double it. Yes, the available current is doubled, but that doesn't mean you'll be able to deliver it into your speaker. Remember, amps are constant-voltage devices, and speakers are constant-impedance loads. (You know what I mean.)


Where bi-amping comes into play is the ability to both reduce clipping of amps with marginal current capacity, and to keep that premature clipping away from the tweeters which, as we know, are most susceptable to clipping damage. By premature, I'm referring to power-supply voltage sagging due to high current loads.


What I mean is that an amp that clips because the output transistors saturate, but isn't taxing the power supply's current capability, won't benefit by a reduction in output load current. Clipping can occur with no speaker connected at all, don't forget. It's load-independent.


My point is that a given voltage across a given-sensitivity speaker produces a given loudness. As long as a single amp can handle the current, that the voltage is now divided between two amps doesn't change anything; the voltage fed to the speaker would be the same at both terminal pairs either way.


Since Ohm's law tells us that the current is equal to the voltage divided by the impedance, The overall current (whether one circuit or two) is the same either way. I absolutely agree that the current seen by each amp has been reduced, which as I said, only benefits a 'weak' amp.


If a single amp is providing, say, 100 watts full range into your speaker, and then you "passively" bi-amp, at the same loudness (i.e., the same voltage), one amp may be providing 40 watts, and the other 60, or any varying amount, but the total power is the same either way. It's the same as a power circuit feeding a pair of lights.


If you were to have a 60 watt (1/2 A.) bulb (woofer) and a 40-watt (1/3 A.) bulb (mid-tweeter) on a 120-volt circuit, you'd have a total of 100 watts (5/6 A.). Now, if you split the load between two circuits, the total would still be 100 watts; 60 W. (1/2 A. @ 120 V.) load on one circuit, and 40 W. (1/3 A. @ 120 volts) on the other. Total? 100 W. (5/6 A.)


So, bi-amping is really most similar to boosting an amp's power-supply current capacity. True (active) bi-amping done 'right', with a crossover ahead of the amps, requires bypassing the speakers' crossover components. You can really screw up a speaker's response characteristics by cascading crossovers, even with an amp between them.


However, bi-amping doesn't truly double power. You may indeed hear an improvement, just as you may when bi-wiring, but it is the current demand that has changed, nothing else. The speaker crossover merely pares away the load on each amp (or amp channel) as the frequencies move out of each section's bandpass range.


Personally, I'd rather have an amp that is just 'loafing along' than need two to handle the load, especially if the amps aren't identical. I do bi-wire, but mainly to take advantage of the Sunfires' "constant current" outputs (1-ohm series resistors) and because I had a spool of #14 laying around at the time.



"That's all I have say about that." - Forrest Gump


Now, amplifier bridging...there's a different subject!


"More power! Arrgh, arrgh, arrgh!" - Tim Allen

__________________

Larry
www.fineelectricco.com

My system (new larger pix!)

Larry, I think it's understood that at a given gain setting you will be providing speakers with the same amount of power, whether that comes from a single amplifier or from two amps sharing the load in passive biamping. I think it's also understood that the "doubling the power" simply means you have more headroom for increased gain than with a single amp of half the power. In other words, you will have the same headroom increase when going from a single 100W amp to either a single 200W amp or a pair of 100W amps. Actually, that's not quite the case unless you can find the perfect crossover point such that both amps provide equal power into their respective frequency bands, but you get the picture.


Doubling the amp channels doesn't make your speakers twice as loud at the same gain setting... but it does allow you to crank the gain to the equivalent of an amp twice as powerful.


Active biamping can do even more, due to the way frequency summation works. You get a theoretical doubling of apparent power simply by switching from passive to active biamping, though in practice it is much lower than the theoretical 2X figure due to the nature of real music content.
 
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