Two Amplifiers Connected in Parallel?

if you search the archives on "biamping" (may want to try various spellings (eg "bi-amping"), you will find a wealth of discussion to answer any questions you have.

I agree with the responses above. I have tried vertical and horizontal biamping with mixed results. Results in my experience are highly dependent on the equipment you're using and the speakers you're driving, and can range from awful to very good.

If you do not use an electronic crossover, this approach has limited usefulness. It works better with transistors than it does with tubes though, as most speaker crossovers are high impedance when they are blocking the unwanted frequencies. This causes a transistor amp to make less power. It may not reduce the power of a tube amp all that much.

If you use an electronic crossover, the introduction of the crossover itself will have an audible artifact. How much has to do with the design, but no crossover will be completely transparent or neutral. In addition, most speakers have nuances of driver behavior which most electronic crossovers don't take into account.

So it can be tricky! My advice is to try it but be careful- the top amplifier outputs cannot in any way have connections to the bottom amplifier (for example- through the speaker's passive crossover), else you could damage something.

I tried it last year .My set up was Aerial acoustics 10T with Rogue Zeus 200W driving bass on both channels and Rogue M150's 150W monoblocks on mids/highs with Rogue Magnum 99 pre dual outputs.I REMOVED the bridging straps at the back of the Aerials.I used this set-up for about 2 months and then tried then Mark Levinson 27.5 connected on the same speakers and I prefer the sound this way better.I am planking in the future to get an active crossover like the Bryston 10B and try it as Atmasphere describes.I was told that the Aerials have a well designed crossover specific to the design so I am sceptical if an external crossover will achieve better results.Your milage may vary,but try and see for yourself.
Best
George

Thanks everyone for the replies. Comments so far leave me on the fence regarding this. I don't have much experience in this sort of thing but intuitively, somewhat makes sense.

If I do try this, here is will do:

Equipment: Pioneer Elite VSX-32 Preamp/Receiver, Two Rega Maia amps, R & L Spendor SP7/1 speakers

Single line L and R outputs from the preamp and connect to L and R inputs on amp1. Use amp1 L and R link outputs and connect to amp2 L and R inputs. This is the parallel connection.

Amp1 R speaker outputs to R speaker tweeter, amp1 L speaker outputs to L speaker tweeter.

Amp2 R speaker outputs to R speaker mid/bass, amp2 L speaker outputs to L speaker mid/bass.

Make sense?

Biamping is a perennial topic, and it is usally asked by folks who know very little about it, except it 'sound' (inthier hhead at least) exciting and sophisticated. Biamping is neither of those things.
If you are going to BUY two amps, your are ALWAYS better off getting one better amp.
Ony if you happen to have two amps laying around, and want to play around, then yeah, try it.
And forst off you would divid a 'three way' speaker system by woofer on one, and the combined mid and treble on the other!
Treble portion of the output is miniscule!!
Say you are using 50 watts for the whole speaker, then 40+ of those watt is going to the bass, and 8 watts to the midrange, and less than 1 watt to the tweeter (on average).
Low frequencies use the majority of the power.
If you do a search about biamping, you can see that a few folks (who know what they are doing, get good results, the majority is almost as good to not as good as one better amp.
Save yourself the hassles and buy one good amp.