Originally Posted by Squishy Tia
Assuming you remain within the rated impedance requirements, yes. Just keep in mind that activating the low impedance mode of the Yamaha AVRs cuts the available power by 50% to all
channels, not just the front L/R. It also increases the risk of entering clipping because with less power to the speakers, you're more likely to hit your "hard ceiling" for volume much, much sooner.
You can drive the low impedance speakers, yes. But you can't really drive
them, if you get what I mean. If you're not in a huge listening room, it may work just fine, but you won't be able to hit Relative 0db (Reference Level for THX listening modes).
It's a tradeoff. You're giving up power for flexibility.
One thing I will mention. Most folks will tell you it's better to run the amp in 8 ohm mode and not turn up the volume to clipping. Generally speaking this works, but the risk on that side is that the current draw could be significant enough to blow the capacitors in the main drive section, so basically with low impedance speakers and AVRs outside the flagship range, you're playing Russian Roulette if you like to listen at anything above roughly 75db. That's the reason for the need for external amps. You'd only need the amps for your main speakers - the rest should be well enough off to where you're not going to blow anything, especially considering that each discrete amplifier section only allows a certain amount of power regardless of whether or not the mains are connected (front L/R).
While you'll be losing some of the power (about 15%) to thermal inversion at the speaker's crossover, using method #2 would work best for you if you intend to bi-amp. Get two identical amplifiers use those to bi-amp the speakers. You could go one step further to actually increase the soundstage and channel separation (and eliminate ANY crosstalk between the L/R channels) by using external amp #1's L/R channels to amplify the Left speaker's lower and upper arrays respectively, and doing the same thing for amplifier #2 and the Right speaker's arrays. If your speakers are properly designed, their crossovers are separate (they'd have to be for speaker to have bi-amp capability without external modification/line level electronic XOs before the amplifier stage). The separated sections might present below nominal loads (4-6 ohms once the connections are separated at the speaker terminals), but external amps generally can handle them. The method I just described is called Vertical Bi-Amping, and you'd be amazed at just how much crosstalk you hear with regular amplifying and with horizontal bi-amping (using two amps; one amp for bass array for both speakers, amp #2 for high array on both speakers). When you lose the crosstalk, you'll definitely hear more of what you've been missing. An apt analogy is this: Rip a CD track to WAV (or AIFF if you're on a Mac - they're the exact same format, just different headers). Create two MP3s from the ripped track. Make the first MP3 using "joint stereo", and make the second MP3 using just "stereo". Joint stereo is what you hear when there's crosstalk. Stereo is what you hear with no crosstalk.
If you want fairly decent, and (relatively) cheap amps, two Emotiva XPA-2 amps will do very well. And you get the added benefit of having XLR connections on them for when/if you get a real prepro. You'd be amazed at just how much line noise you lose going from unbalanced to balanced (XLR) connections at both the preamp and amp ends. Only problem there is...well, finding a good prepro for less than the top end AVRs. That's my problem right now. Well that and I hate, loathe, and despise Audyssey's current implementation and the fact that my tweeters literally disappear with room correction activated via Audyssey.
What an amazing post!!!
This is why we all are here to share outstanding info with others, thank you!
So! based on this facts from amps, bi-amps, psu`s, etc...
I have this candid question... but first! my setup is this:
Fronts: B&W 683 with bi-amp terminals
S: B&W 685
SB: B&W 685
Center: B&W HTM61
with the mighty Supercube I
if I hook to my actual system an exactly second RX-A2000 and wanted to try
the Vertical Bi-Amping setup you mention... how exactly do I hook my speakers? and I guess XO on the side of my speakers is good enough to handle this kinda setup!
This is the scenario you kindly gave us:
AMP #1 L/R signal goes to the LEFT SPEAKER terminals:
left goes for tweeter and right goes for woofer?
AMP #2 L/R signal goes to the RIGTH SPEAKER terminals:
left goes for tweeter and right goes for woofer? or back wards?
AMP#1 is for decoding? and the rest of the speakers? right?
Sorrryyy for my silly questions, I am just a little way over my head for XO crosstalk and want to understand exactly.
(maybe is more the language barrier than technical barrier)
All the best,