Aleph 5 passive vertical bi-amping?

Thanks for your responses. It sounds like it could offer a good improvement in the sound, particularly with regards to dynamics and control - which is what I'm after.

The Alephs work best with the balanced XLR inputs. This will mean that I need to split each output signal from my preamp (L and R) using some sort of Y adapter. As far as I can make out, this is the only way that I would be able to connect up what would become the 2 Left and 2 Right inputs on the power amps. Does anyone have any suggestions about adapters or specially terminated XLR cables? If I can get a good adapter, that would enable me to continue using my XLR Nirvana S-X interconnects, which I am loath to part with!

The advantages of vertical bi-amping are that each amps power supply only has to drive the bass on one speaker. You will experience greater volume and dynamics, with a more effortless musical presentation. And used Aleph amps are reasonably priced.

On the other hand horizontal bi-amping, like one reply states, still requires the that the amp driving both channels of low frequencies still puts a greater demand on that amps power supply. This defeats the advantaqges. Anyway, for sonic balance both amps should be identical.

Try driving the bass with any old ss amp at hand (with sufficient output)and check out the result -- before you actually buy an Aleph. Your pre would have to be capable of driving a more difficult load (two paralleled amps). I expect there wouldn;t be a problem.

My GPs are the original mk1 with the bi-wire posts. Therefore I was just planning to use one channel for bass and one for treble, keeping the internal crossovers. At the moment my preamp would need Y adapters (XLR) to separate the signal to the 2 amps, unless I go for a preamp with 2 sets of outputs to enable bi-amping. I've never done this before, so I hope I haven't overlooked anything! Thought it would be an interesting experiment that should yield some benefits to make it worthwhile?

Well, you'd be doubling the power (that's +3db /side). But how do you propose to do that -- unless you disconnect the woofer from the internal xover & introduce an outboard low pass. Asaik, they don't have double binding posts (i.e. "biwire"). Cheers

Speakers are Sonus Faber Grand Piano floorstanders. They are rated up to 200 watts, so I don't think there would be a problem there. Was hoping to get some extra benefits of using the 2 amps, ratehr than having to worry about tuning crossovers to start with?

That really depends on the spkrs rather than the amp. I'm sure the Aleph won't mind. But passive biamping is a bit of overkill -- no? Why not use a passive line level xover instead? Far better results there...