which bi-amp is more effective?

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Adamo

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I'm thinking of going the Bi-amp route in lieu of the bridged route when my two 2 ch amps get here. I was thinking going Left speaker: amp1 gets HF and amp 2 gets LF, and Right speaker: Amp1 gets LF and Amp2 gets HF. This way I minimize stress on the amps and still retain headroom. Is there a better way to do this (external xovers aside)?
 
I think that's what most people do when they passively bi-amp. I suppose the other way you could try would be to use the two amps as monoblocks. That is to say, you would use Amp 1 (left channel) to power the panel and the other set of outputs for the woofer. Then you use Amp 2 (right channel) to power the panel and the other set of outputs for the woofer.

Erik
 
Ek, that sounds like a good idea as well as it shorten the cable length by a few feet. How much experience do you have with MLs? I ask because I'm in NOVA and would love to have an experienced ML owner to drop by and help me with the best set up for them.
Adam
 
I am perhaps considered to be a newbie by this forum's standards! :bowdown:

I received my first pair of ML speakers in 2001. So I guess it's been nearly 7 years for me (where does the time go?!).

There are a number of seasoned ML vets in the NoVa area. In particular Dan (DTB300) lives in Maryland and we get together every now and again for various listening parties. Last year Dan hosted a nice party at his house that was a lot of fun. I believe he is planning another event in June.

My girlfriend lives in Alexandria and I am in the DC area at least once or twice a week.

My knowledge of passive bi-amping is somewhat limited. However, there aren't that many ways to do it when you are using two amps. So I guess you could try it the way you proposed in your original post or the way I suggested. Hopefully you have enough cables for all of this!

Another point to consider: I am assuming both amps are the same, i.e. two Rotel 1070 amps, or whatever. If that's the case, then I suppose you don't need to worry about the gain of the amps. If you were using to two very different amps (one SS and the other tube) then maybe you'll need a way of externally controlling the gain.

Erik
 
I have experimented extensively with this topic. My ears tell me that keeping the amps on completely separate channels sounds best... ie--Amp#1 handles left channel and is bi-wired to that speaker. Amp#2 is...well you get the picture.

This arrangement, what I call external bridging, gives me the best soundstage and depth of field. Why it is, I have no idea... but a dealer once told me that it was due to the improved channel separation.

The only thing I do to even out the stress on the amps ( the amp channels that drive the ESLs have to work harder ) is to swap the wires at the speakers every few months. HF wires go to LF, LF wires to the HF terminals.

So good luck with this. By all means do your own experimentation, and let us know how it turns out. ;)

~VDR
 
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VDR, his XPA-2 amps are on pre-order and have been for, I don't know, 8 weeks now. BTW, what you called external bridging is commonly called "vertical bi-amping".
 
Adam,

Why do you think you need to stagger LF and HF channels in that way? If it really is to reduce stress on the amps then I am beginning to worry about your listening habits and your ears. Can you hear me. Hello? Hello!! Well, you get the idea.

I'd simply start with a bridged config then switch over to a vertical bi-amping config. See what you like better. Then compare the winner with the horizontal bi-amp option.

I seem to recall that Arcam suggest horizontal over vertical bi-amping. I forgot why and I can find the white paper though.
 
Hey guys, sorry I haven't posted in a few on this one. Ralf is right...except I've had these on preorder for even longer than 8 weeks. I'm beginning to wonder when they will ever show up. I'm not worried about the stress due to crankin the volume up to a ridiculous level (although for a few min sometimes it's nice to "challenge" the amp), but was just conforming to the "less stress the better" logic for best sonic response possible. I have no doubt the Bridged route will give me an insane amount of headroom. Like you said though Ralf, I do want to compare and see what sounds best. I almost bought two Classe CA-201s the other day because I'm getting impatient.:confused:
 
I think that Vertical bi-amping is not suggested in manuals due to some phase issues that can be caused by the bi-wiring on the speaker end. I'm no expert in that field though.
 
I think that Vertical bi-amping is not suggested in manuals due to some phase issues that can be caused by the bi-wiring on the speaker end. I'm no expert in that field though.


Hum, I'd take that with a big grain of salt. In speakers like the ML's, where the high-pass and low-pass are separate passive networks, there should be zero phase difference between driving them with one channel of amplification (across both binding posts) or bi-amping them (one channel per segment).

Vertical bi-amping is a great way to bi-amp a speaker. For one, it ensures that gain is absolutely the same for panel and woofer, something that when using two amps (one for woofers and one for panels) can't necessarily be guaranteed, even if using same model same manufacturer (minor though that may be).

Both models actually work, but horizontal requires taking care of gain.

BTW- I horizontally bi-amp (with active X-overs) and measure and adjust gain very carefully.
 
Jon,
I will be passively Bi-amping, as I will be still using the internal x-over in the Odyssey. I can't imagine gain being so different in same make/model, but I would agree there has to be some margin for error there that makes it not exact. I hadn't thought of the fact that the panel and woofer are completely separate anyhow, so I guess vertical bi-amping is still a good posibility. The problem with experimenting with both is the need for a bi-wired on one end speaker cable, and then two separate cables per speaker for Horizontal. I have plenty of speaker cable, but no bi-wired cable.
Adam
 
Jonathan,

I still could not find the Arcam white paper but as far as I am concerned vertical and horizontal bi-amping should be equivalent if the same make and model are selected and if both have the same amount of "miles" on them. Under these circumstances I'd probably go vertical for practical considerations. However, I am having trouble following your gain argument. Amplifiers of the same make and model and even bought from the same batch would surely meet the same gain and sensitivity specifications, no? If they did not I would be worried just as much about L/R gain imbalance between the amp boards in the same amp!
 
Adam, why do you need bi-wired cables? A bi-wire cable is basically a Y cable whereas for bi-amping you need two (hopefully identical) cable pairs per amp/speaker. Whether you bi-amp H and V does not change that. I must be missing something.
 
Ciao Ralph,

if I am bridging at the amp end and then bi-wiring at the speaker end, I need special cables for that unless I double up on the spades. I don't like doing that. I'm probably going to have Ek drop by if and when the amps ever decide to show, and we'll do both bi-wire, and Vert/Horizontal bi-amping and see which sounds best to our ears. If you weren't on a different continent, I'd invite you to join us!
 

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