Bi-amping with "split mono-blocks"?


Has anyone ever used a pair of stereo tube amps to bi-amp speakers in a configuration such that each speaker has it's own stereo amp driving both the upper and lower blocks?

I think this would have the effect of separating the channels effectively as if using monoblocks and also allowing a bi-amp configuration to the speaker.

FWIW, I'm running a Premier 11A into VR4JRs and I've have a desire to try bi-amping but I also want to try monoblocks. I thought that if I bought another Premier 11A instead of trading up to the Premier 12, I could have benefits of both biamping and monoblocks. The combined power of two Premier 11As would be about the same as a Premier 12. Also I'm thinking I could use KT90s on the bass path to get the extra I want there and use 6550s on the uppers to retain the sparkle that the KT90s seem to lack.

Any thoughts?
mcmiller
I am using six stereo amps with all 12 channels actively driven. Each stereo amp is run as a mono-bloc though i.e. both channels of one amp sharing the load on the right bank of tweeters and both channels of an identical amp feeding the right bank of tweeters, etc... This same system using multiple other amps is utilized all the way down through the frequency range.

This approach increases channel separation by reducing crosstalk, improves dynamic range, increases headroom, increases control over the drivers via reduced sag in the power supply, improves sound quality by allowing the amps to stay in Class A longer due to the reduction in pull from any given channel via sharing the load, increases the damping factor by increasing the impedance that the amp would see as compared to only having one channel driving all of the drivers in that bank, etc...

In the future, i may end up going to a four way system, which will require two more stereo amplifiers and a crossover change. I think that this will give me even better performance, albeit at increased cost and complexity. Like anything else, the pursuit of excellence in any given category is met with diminishing returns and increased expense.

Other than that, you are on the right path and what you want to do should work out quite well. So long as you can find a way to gain match the individual amps to each other AND gain match the "hi" & "lo" channels of each amp, you should end up with the best of both worlds i.e. mono-bloc's that are voice-matched to your listening preferences through-out the frequency range. This is exactly what i did, but with the aid of an active crossover. Sean
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Sean, good point about letting the amps ride in class A longer. I suspect this may have a lot to do with improving the sound with multiple amps.
Hi,

I have the exact situation that you are describing. I use separate stero amps to power my bi-wire N802's. I use a spliter on the pre amp to give me two outputs for each channel. I use one side of the amp to power the bottom portion of the speaker and the remaining channel to do the top portion. I have found this arrangement to be very dynamic and provides a lot of headroom. My amps are capable of being switched to mono but the manufactor recommends running them in stero which gave me the idea of using one amp per speaker. I also have tried running them with one amp to power the left / right bottom and the other amp left / right top. Either configuration works I don't know if there is a sonic or performance benifit in either option.
Big benefit to biamping; I've doubled everything, the speakers (Eminent Technology LFT8A's), the interconnects, speaker cables, amps...so it totals now 8 amps (using multichannel amps) driving the four Eminents. In order to accomplish it, had to get a preamp with dual main outs, then split those four outs! Rogue Magnum 66 has internally switchable tape out as second main. Works well.

Fabulous sound! Far, far outperforms the basic one speaker, one amp setup. Has put me into a different universe of sound.
If you don't stick with the same family of amps, you'll get into the never ending game of exchanging them, similar to interconnects. It'll just introduce another variable to drive you crazy.

You do have to pay attention to gain; one of my multichannels I use is 165/ch, the other 200/ch. The gain difference is noticeable, but I was able to combine them in such a way that it works incredibly well (used the 165/ch on bass, and supplemented with twin Vandersteen subs; much improved sound putting more watts to the panel speakers). But if you don't have matching amps, you could be asking for complications.

Since I've tried bi-amping, I know I'll never go back to anything else. If you have very inefficient speakers, the change will be night and day if you bi-amp. More control, headroom and ease with which the music is delivered.

Everything got much better.