Horiz/Vert Biamping

I see many references to horizontal vs vertical biamping and the definitions seem to be contrary to how I would define these: I would define them as such:

Vertical: Defined as one amp for the Top freqs and another amp for the Bottom freqs.
Horizontal: Defined as one amp for the Left channel and another for the Right channel.

But these above definitions do not seem to be what anyone else here uses so I am curious as to why they are defined exactly the opposite.

And I can see there would be one major advantage for each situation. When the amps are matched, better channel separation would be expected if an amp is used for each channel. But to have an amp for the top and one for the bottom might bring on more openness in the mids and highs as the amp driving that range is not stressed by the low freq demands on the same power supplies in a stereo amp. I guess true dual-mono stereo amps would alleviate this or is this still not entirely the case? Or is it really a better way to go with a different amp optimal for each of the 2 freq ranges? And if so, what about synergy around the crossover point between the two amps' sonic differences?

Any thoughts or experiences here would be greatly appreciated. This mainly pertains to Magnepan Series 3s but other speaker usage would be interesting.

It is contrary to what you believe to be true.

Horizontal: One amp runs the mids/highs of both channels and one runs the lows.

Vertical: One amp runs the left speaker, one runs the right (said to minimize interchannel crosstalk).

These definitions are verified to be correct by several audio manufacturers. I, too used to think the definitions were as you describe above. Ah, the many not so straight forward definitions of this hobby (obsession to some).
Funny,I always thought that Vertical amping implied using individual amps for each driver in each channel.

Vertical amping as you describe is using Mono's for Bi-amping capabilities it is not vertical amping in the true sense of the word.

Horizontal to me is using an amp for the High\Mid Drivers for both channels and one for the Bass drivers for each channel,but you could also have seperate amps for each of the Mids and Tweeters paired channels which would still be Horizontal amping.

I am at present looking to Vertical amp 3-way speakers using 3 sets of Mono blocks thus having a seperate amp for each driver. That is 6 amps or as stated 3 sets of monoblocks.

Atleast that is what I think.
Look to Marchland and Bryston!

They both make outboard XO's.

There is alot of dispute about this,but it is very beneficial once you understand it and what is going on.

Recently there was an article in a mag about it and it's what professionals are going to.

Like I said once you understan it,it is easier to see the Bene's of it.

Monoblocks for each channel and bridging are different .This setup is better and is different than that.Less distortion,crosstalk,more efficient for the amps to drive the speakers.

I will try to explian it again later if you wish.The XO is then connected to the amp .Has nothing to do with how many inputs there are on the preamp.

It will defeat alot of the problems of room synergy because it allow for the XO to be tailored to whatever is best to accomidate the drivers to the room.Thus it is sort of like tone controls ,but better.

Did I explain that so you can understand it?
I am more confused as ever. Abex writes, "Horizontal to me is using an amp for the High\Mid Drivers for both channels and one for the Bass drivers for each channel, ..." In his case, one amp drives the top freqs and one amp drives the bottom freqs. How does the true meaning of the word, horizontal, apply to this configuration at all?

Does not horizontal imply a distinction between left and right; it has nothing to do with going up or down. Where was Mr. Spock when we needed logic to define what otherwise would be so simple.

Anyway, silly semantics aside, are there any members here who have tried dedicated amps for each channel vs dedicated amps for the top and bottom frequency ranges? And what were the sonic benefits of each .... if any significance existed at all?
I have tried to explain this a few ways,but I'll try one more time.

3 Types of Amplification!
Horizontal Amping--Does not require Monoblocks
Vertical Amping--Need Monoblocks

Horizontal means you can use 1 amp to drive the woofers in both channels and another amp to drive the Tweeters in both channles and another amp to drive the Mid Drivers in both channels.So you have 3 amps driving particular drivers in both channels.

Most speakers that allow to use seperate amps that are 3-way speakers only have a 2 sets of binding post which means they combine driving the Mids\Tweeters as one.Which in turn means you would have :
One amp for the L\R Channel Mid\Tweeters
One amp for the L\R Channel Woofers
That is Horizontal Amping because you are using the amps to drive the same drivers in L\R Cahnnels and even if you are able to use another amp to drive that set of Tweeters in both channels by adding another amp you are still Horizontally driving the speakers

Then you can get a 3-way Outboard crossover unit which allows for using a seperate amp to drive each driver.This is Vertical amping.
So lets start with the Left Channel in a 3-way speaker using Monoblocks:You would need 3 sets of Monoblocks
1 amp for the left channel Tweeter
1 amp for the left channel Mid Driver
1 amp for the Left Channel Woofer Driver
For the Right Channel
1 amp for the right channel Tweeter
1 amp for the right channel Mid Driver
1 amp for the right Channel Woofer Driver

Bi-amping is just adding power and nothing more.It is not really advantageous from any other point of veiw.Horizontal and Vertical amping helps with efficientcy .Verical being the most advantageous because it is using a Dedicated amp for each driver.It also allows for less crosstalk and less distortion from occuring.

Here are examples of Crossovers

Another way of explaining it.Maybe this will be better.


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 which allows for better speaker to room interaction.

Bi-Amping has no value other than more power.

I hope that explains it! 8)

Here are examples of Crossovers
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.
Think of vertically bi-amping as turning the amp on its' side i.e. so that it standing vertically on the shelf or next to the speaker rather than laying down ( as it normally would ) horizontally. Once you get the picture of the amp standing vertically, it will remind you that you are running one channel for the lower section of the speaker and the other channel for the upper section of the same speaker.

To further imbed this easy to remember idea in your head, think of how your speakers are spread out horizontally ( or side to side ) in the room. Horizontal bi-amping does the same thing i.e. uses one channel for the lows ( or highs ) of one speaker and then spreads the other channel of the amp over to the other ( horizontal ) side of the room for the equivalent section of the other speaker.

There are benefits to each type and which works best will depend on the type of speaker load that you have. If one is running a speaker that has a highly reactive mid / tweeter section ( E-stat's, etc... ) with multiple woofers, my opinion based on personal experimentation is that horizontal bi-amping works best. Since both sections of the speaker are going to pull pretty hard on the amps power supply, which is common to both channels in most designs, both the bass and treble may "suffer" at the same time. Having a dedicated amp for the treble with a separate amp for the bass helps to ease the load on each amp and power supply. Since it is unlikely that both frequency ranges would be "surging" at the same time, effectively narrowing the frequency range that each amplifier / power supply must feed can increase efficiency and minimize the stress on teh system as a whole.

If one has a "normal" speaker with relatively mild loads like cone mids, dome tweeters, and a woofer(s), which woofers always need quite a bit of power and have larger amounts of reactance / reflected EMF to deal with, one is typically better off with vertical bi-amping. This allows the power supply to shift most of the current draw to where it is needed with the woofer on one channel while it pretty much "coasts" with the channel feeding the mid / tweeter section of the speaker.

Obviously, these are generalizations and each situation is different, so you'll have to do some trial and error and see what you think works best. The one advantage to vertical bi-amping is that there is less potential for crosstalk to occur from the left to right channel than if both channels were being used in a normal "stereo" fashion. This is because, in effect, you now have "two channel monoblocks" feeding each speaker.

Having said all of that, i can understand the confusion between the vertical and horizontal nomenclature that we use. I think that this comes from the fact that most systems are installed in some type of rack with the equipment arranged in a vertical array. With this configuration, it is easy to assume that "vertical bi-amping" would make use of the two left channels of the amps that are stacked on top of each other for one speaker and the two right channels of the amplifiers feeding the right channels. This would use the two channels that were "vertical" to each other, making this a logical conclusion. The other method, using the two channels of one amp, which are typically laid out side by side, would be the "horizontal" mode of bi-amping according to this type of logic. Too bad "logic" doesn't always work with audiophilia : ) Sean
It was the designer of my speakers that first brought the equation and recommendation up to me for Vertical amping and then I saw an article in one of the major Mags where the reviewer stated that he would not even consider thinking of a new speaker today unless it gave him the ability to do Vertical amping.

The more I ponderd the idea the more it made sense,but to explain it is a total nightmare.I have been to 3 BB's where people have gotten the explaination screwed up which in turn played with my head trying to explain it and I have been into audio for quite some time now.

The disadvantages are using more Power and more wires,but the benefits outweigh the drawbacks if you want the best you can get.Then again it must all gel right.

My speaker designer is making an outboard XO(3-ways) with my speakers which should be ready by the end of the month.

One thing that is really driving me nuts is trying to find the right amps to use.I have a modified B&K ST-202 and have been waiting to see if the new LeAmpII's are better than the originals which of what I understand have gotten less than stellar exceptance in the audio community.But the new ones are suppose to be a breed apart from them.Mike Barnes of nOrh says they are comparable to SOTA stuff and they only cost $400 per Monoblock set.If it's true I want 3 sets.Then again like the old saying goes if it's to good to be true it usually is.

Abex: One can not buy the capacitors, transformer, chassis, heatsinking, output devices, etc... for a truly "SOTA" SS amplifier for $400. Bare in mind that i'm talking wholesale costs and volume purchasing here also. As such, i would not get my hopes up too high in terms of out of the box performance.

Having said that, the new design might make for an excellent platform for upgrading / modifications. One can devise an excellent circuit yet compromise the performance of the unit by building it to a low price point using lesser quality components. As such, replacing the "mass production" low cost parts with higher grade parts can turn some "budget" products into truly "kick ass" performers. Sean
Yes,I realise this to that is why I have a Modified B&K ST-202.I am waiting for the opinions of the LeAmpII's from some people at the Midwest audio show going on this week.

If worst comes to worst I will try to find some Mark Lev amps in the future to Horizontally amp the speakers.