Passive bi amp?

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I've tried almost every possible bi-amp (and even tri-amp once) configuration in the past... and I always end up reverting to a single set monoblocks. I know others have had great experiences with multi-amplification per channel... but for me, nothing gets as close to "right" as a pair of well designed monoblocks. That configuration just always seems more coherent and focused to my ears.
 
has anybody out here
Tried passive vert or horizontal bi amping
On their ML"S and wanna dicuss it? :D

This has been discussed in numerous posts. Yes, a number of members bi-amp - especially with the older generation models.
 
Straight Up

Hi Bill,

Mono blocks if you can afford the $ and real estate, otherwise I prefer vertical over horizontal. The sound is better integrated IMHO. The theory behind this is that same signal is feeding both sides of the stereoamp pressed into service for each channel (L/R) and that current draw on the power supply is therefore the same.

Horizontal bi amping brings in both L and R channels with their differing signal demands on the same power supply of their amp. Whilst bass signals are largely mono in nature,the mid and high signals are the most sensitive to being affected by background power draw demands of the other channel on the same amp.

I have tried both but vertical wins for me. The real challenge for me is how to split the incoming signal cable cleanly before going into each amp, Y cables are messy, single ended is easier but try splitting balanced signal cables.

As always, my 5c worth

Fjeff
 
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I have tried both but vertical wins for me. The real challenge for me is how to split the incoming signal cable cleanly before going into each amp, Y cables are messy, single ended is easier but try splitting balanced signal cables.
Jeff, there is always the option of internal surgery, where you connect the inputs together. I wonder if a manufacturer would consider doing it for you so the warranty is not voided.
 
Hola... just keep in mind also, that the input impedance will drop to the half on both amplifiers... happy listening,
R.
 
Hola... just keep in mind also, that the input impedance will drop to the half on both amplifiers... happy listening,
R.
Roberto, good point, but I think you mean that the preamp will now see half the input impedance, not the input impedance of the two amps will drop.
 
My system is passively bi-amped with tube monoblocs on the panels and solid-state stereo amplifier on the bass. What is your question? I have posted numerous posts on this subject. Please do a search.
 
Roberto, good point, but I think you mean that the preamp will now see half the input impedance, not the input impedance of the two amps will drop.

Yes, what matters is the preamp impedance, not the amps... correct!... happy listening.
 
To clarify, because I can't help myself, when a single pre-amp output feeds two amps in parallel, the first order effect (by far) is that the two amps will appear as a product-over-sum load to the pre-amp's output. For example, if both the amplifiers have an input impedance of 100K Ohms, then the parallel combination will be 50K Ohms. I don't know of any modern pre-amps that would have any trouble driving 50K Ohms (or even 10K Ohms for that matter). Though I suspect the golden-eared among us might claim to hear some sort of aural delta... and perhaps they do.
 
Right tsv_1, that it is correct too. It is very difficult to find amplifiers with an input impedance lower than 10k ohms... sensitivity will might vary also. I had long time ago two Conrad Johson MV-50s. What I did is to bridge them. Did connect the inputs internally and took off the input 100K resistor to ground of the right channel, and left only one at the circuit... and at the binding speaker terminals, connected 16 ohms + of the left with the 16 ohms+ of the right (this connection gave an 8 ohm tab) and -L with -R and connect the speaker here. Because the signal was the same for both channels, did work. So I had 100 Watts mono-blocks for fun. At that time, I was having fun with Magneplanar speakers, also use the 8 ohms tabs as 4 ohms for the Tympanies IIIB. I got some good juice at that time. Happy listening,
R.
 
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