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Posted By: emedwhat Bi-amping and M22ti - 10/04/05 09:01 PM
This is maybe silly question but what is bi-amping and is M22ti bi-amping compatible?

Posted By: BlueStater Re: Bi-amping and M22ti - 10/04/05 09:35 PM
Bi-amping generally means using separate amplifiers for your mids/highs and your woofers. This is done with "high-end" speakers and you will find this capability with some of the larger Axiom offerings. The reasons for this that I have seen are many. Some audiophile types like to power the highs and lows with different amplifiers, claiming to match the characteristics of each with the perfect amp. Some claim that the internal crossovers in speakers are inherently inferior to outboard crossover networks. Some do it because it is expensive and as far as they know $=Quality. The M22's cannot be bi-amped, at least not "off-the-shelf" so to speak. Bi-wiring means running separate wires from the same amplifier to the high and low's individual binding posts. I really don't know what the benefit of this may be.
Posted By: DJ_Stunna Re: Bi-amping and M22ti - 10/04/05 10:10 PM
As BlueStater correctly stated, the M22s (or any of Axiom's bookshelf speakers) cannot be bi-amped or bi-wired.

First, I think it is important for me to mention that there are two types of bi-amping: passive bi-amping and active bi-amping.

Passive bi-amping refers to running two amplifier channels in parallel without an external crossover. For this, you leave the internal speaker passive crossovers intact. This offers the benefit of increasing total power, but basically nothing that will significantly affect the sound quality. (This is what I do with my M60s. I do this instead of active bi-amping because I do not want to mess with the internal crossovers, and they sound great to my ears just the way they are. I also value having a warranty. )

Active bi-amping refers to using an external electronic crossover before the power amplifiers (but after the pre-amplifier) to separate the signal into a low component and a high component based on the crossover frequencies you select. To do this, however, you must open up your speakers and disable the internal passive crossover network. This will not only improve the power output by simply adding up the total power, but it will increase sound quality for a few reasons.

One reason that active bi-amping improves the audio quality is that an electronic crossover is generally going to be of higher quality than a passive crossover. These will have higher slopes and thus will allow you to more precisely specify which frequencies will go to what drivers.

Another benefit of active bi-amping is that it lowers the audibility of the distortion as a result of clipping. Distortion is most easily heard in the mid to high frequencies. Because treble requires much less power to get the same apparent loudness, you will most likely not even strain the treble amplifier even when the bass amplifier is clipping.

Yet another advantage results from what I just said above. Since clipping is prevented in the midrange and treble speakers, and because tweeters are the most easily damaged by clipping, you are basically ensuring that if they get damaged, it is not due to amplifier clipping.

I hope this was somewhat useful for you.
Posted By: BlueStater Re: Bi-amping and M22ti - 10/04/05 10:13 PM
Thanks for the amplification and clarification! Any thought on bi-wiring?
Posted By: RickF Re: Bi-amping and M22ti - 10/04/05 10:16 PM
Whoa, that poor stick fella ^ fell a long way on your reply DJ_...got any backups?


Posted By: pmbuko Re: Bi-amping and M22ti - 10/04/05 10:21 PM
Biwiring? Waste of money. Here are my thoughts on it from a thread two years ago. (Wow, has it really been that long?)
Posted By: BlueStater Re: Bi-amping and M22ti - 10/04/05 10:25 PM
I thought as much. I'm still working on fine-tuning my sh!t-filter as far as audio goes. What's the line from Apocalypse Now? "Out here the sh!t piles up so fast you need wings to stay above it?"
Posted By: DJ_Stunna Re: Bi-amping and M22ti - 10/04/05 10:27 PM
In reply to:

Biwiring? Waste of money.


Exactly. It is pointless... All it does is lower the resistance of the wire, but this can be achieved just as easily by using a lower gauge (thicker) wire.

Edit: Haha BrotherBob... My response was kind of long, so I guess I was a bit rough on my stick figure.
Posted By: emedwhat Re: Bi-amping and M22ti - 10/04/05 10:29 PM
Thanks folks. I am sorry to hear that m22ti can not be done but what to do.
Posted By: BlueStater Re: Bi-amping and M22ti - 10/04/05 10:35 PM
Now, you find that your passive bi-amped set up does sound better? Cleaner at high SPL? Better in general? I understand that this would put a lower load on each amp, therefore getting essentially more SPL with less strain on the amps and thus reducing the chance of clipping. But say at 88-100 DB does it actually sound better? I am just wondering.
Posted By: DJ_Stunna Re: Bi-amping and M22ti - 10/04/05 10:40 PM
I wouldn't worry about it if I were you emedwhat. The reason is that you are basically doing an active bi-amp since you are using bookshelf speakers and using a subwoofer to do the bass notes. The only difference is that the woofer is not in each one of the speaker cabinets, but rather, it is in its own enclosure which is optimal for the driver's Thielle-Small Parameters. It'd be a bit pointless to bi-amp bookshelf speakers because you would only be separating mid frequencies from high frequencies. Neither of them require that much power in the first place, assuming of course that you have the crossover and subwoofer enabled in your receiver.
Posted By: DJ_Stunna Re: Bi-amping and M22ti - 10/04/05 10:43 PM
In reply to:

Now, you find that your passive bi-amped set up does sound better? Cleaner at high SPL? Better in general? I understand that this would put a lower load on each amp, therefore getting essentially more SPL with less strain on the amps and thus reducing the chance of clipping. But say at 88-100 DB does it actually sound better? I am just wondering.


I would be lying if I said that I could actually tell the difference when I passively bi-amp given the same loudness level. If the amplifiers are equivalent, passive bi-amping should never sound better at any given non-clipping volume. This is just like how bi-wiring should never sound better.

This may make you ask why I do that at all... Well, I have a 7.1 channel receiver (the Pioneer VSX-1014 Tx). This receiver gives you the option to use 7.1, 6.1, or 5.1. If you select 5.1, the receiver allows you to either use the extra two amplification channels to bi-amp your main speakers or set up a multi-room system. Since I no longer have high quality speakers in other rooms, I chose to bi-amp my main speakers. I like having those extra 3 dB of dynamic range if I ever need them.
Posted By: BlueStater Re: Bi-amping and M22ti - 10/04/05 10:51 PM
Thanks Will.

That's nifty. Mo' power. Power good. I like that.
Posted By: emedwhat Re: Bi-amping and M22ti - 10/04/05 10:56 PM
I read this article then I needed to understand the issue.

http://www.ultimateavmag.com/avreceivers/605arcam/index1.html

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On the Arcam, however, a menu option allows the two extra amp channels to serve your main L/R speakers in bi-amp mode. In my system, the result was a dramatic improvement in overall sound quality with both stereo and multichannel sources. (Speakers with bi-amp capability have separate pairs of input terminals for the high and low frequencies, which are normally jumpered together. In a bi-amp situation, the jumper is removed and each speaker is fed a full-range signal from two separate amp channels via two separate speaker wires, one connected to the speaker's HF terminals and the other to its LF terminals. Most high-quality full range speakers are bi-amp compatible.) "The text was taken from the article writen by Lawrence E. Ullman, June, 2005 at UltimateAV.com"
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Posted By: tomtuttle Re: Bi-amping and M22ti - 10/04/05 11:02 PM
Lawrence Ullman drinks the magic Kool-Aid.
Posted By: bridgman Re: Bi-amping and M22ti - 10/04/05 11:53 PM
>>I read this article then I needed to understand the issue.

>>"Most high-quality full range speakers are bi-amp compatible"

IMO bi-amping became largely obsolete the day that powered subwoofers became the norm in home theater systems. When you are running a home theater system and sending everything below 80 Hz to a subwoofer, you already HAVE active bi-amping in every sense of the term... electronic crossover, separate power amps, yadda yadda.

If you are running full range music speakers without a sub, where the same speaker is handling the deepest bass and all the other frequencies, and you are running at extremely high power levels, then bi-amping is still valid and beneficial.

I think the author was talking about larger speakers like Axiom M60 or M80, which are all configured in exactly the way the author described. Honestly, I don't know ANYONE who would want to bi-amp a bookshelf speaker like the M22.
Posted By: JohnK Re: Bi-amping and M22ti - 10/05/05 03:49 AM
Em, there's no good reason to be sorry that the M22s don't provide for passive bi-amping(or biwiring)since it has no significant benefits. Each channel of the amp still carries a full-range signal and each section of the speaker still has only the power of one amp channel available. For example, if two 100 watt channels were involved in a passive bi-amping arrangement, each speaker section would still have just the original 100 watts available, not 200 watts. As Will pointed out, you're already receiving the advantages of a form of active bi-amping when you use the bass management of your receiver to send separate frequency ranges to the sub amplifier and the speaker amp channels of the receiver. As far as the review in Ultimate AV, I can't find that comment to be any more credible that any other audio illusions we often read about.
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