Does anyone play two pairs of speakers at the same time?


I have found that certain combinations of speaker pairs produce a better sound than the single pair alone. For example: Klipsch Quartets and PSB Image 4T (new tweeters from Vifa) Quartets inside pair and volume matched to PSBs. I have done this over the years and found some great combinations.
aburnhamuu
I’m glad to see this topic, so this is my story.  I’ve been building my system over the past few years, when I began with Magnepan 1.7i and Odyssey Audio amps/Candela preamp.  I then auditioned Focal Sopra 2 and Electra 1038BE2’s of which I preferred the 1038’s over the Sopra2.  On to Pass Labs X250.8 and Pass Labs XP-20 preamp.  Then I purchased all Acoustic Zen cables (Absolutes and Hologram 2’s).  Also Mutec’s MC-3+USB and their master clock Ref 10.  The 1038be2 were performing beautifully, in fact I didn’t think I could be happier as the imaging, soundstage and ability to give me all the emotion of a performer/performance as possible, was giving me everything I had dreamed of in a high end system.  

But there was one thing which was bothering me and didn’t sound perfect.  It was with vocals.  They just sounded slightly restricted, somewhat truncated, or not naturally expanding in space.  I tried repositioning etc. to no success.  I was convinced it may have had something to do with the size of the speaker cabinets.  Nothing would convince me otherwise and it was bothering me.  Yet these speakers sounded fantastic across so many different types of music.  Precise imaging and sound which would soar wide and high.  There was one other issue too, now that I think about it.  I wanted to hear the instruments larger and more life sized.

It was November when I saw the ad for Upscale Audio and the 1/2 price of perhaps the last pair of Scala Utopia 3 being sold new in the US.  I couldn’t resist.  After putting around 1000 hours on them (as well as installing isolation feet), I was very impressed with the scale of instruments and vocal reproduction was just sumptuous.  But...
Songs which used to move me didn’t quite give me the same reaction as did on the 1038be2.  Nor did they go as wide.  Were these wonderful new speakers just too laid back?  Then depths of the sound stage reach was much deeper and the sound was so refined,  but I found myself playing them louder than the Electra’s hoping to extract some of the characteristics I enjoyed with the Electra’s.
I took my Electra’s back out of their boxes and placed them just outside of the Utopias (separated by a scant inch and slightly ahead (approximately 2”-3”) to compare the sound.  I was pleased once set up, as the tweeters lined up almost perfectly.  Both gloss black, they looked like good friends next to each other.  One, a touch shorter and wider, the other a bit taller and slim.

Yes, the 1038’s performed as before in all aspects.  So I pulled out my Odyssey Amp and just for curiosities sake I ran both speakers at the same time through the two different amps.  (Both pre-amped  through through the XP-20).

Oh I was on to something!   First tracks I tried were female vocals and the problem of the 1038’s alone (somewhat restricted vocals) was gone, both sets of speakers were acting as one, but better and bigger.   Perhaps with the signal split between the Odyssey and the Pass labs, they were not in perfect harmony, but it was very close.   

So I ran spades from one Focal and banana plugs from the other into the Pass Labs X250.8 alone.

A revelation. I was now listening to One speaker with eight drivers per side, working in absolute harmony.  A speaker greater than the Scala alone, big, bold, precise, natural and delicate if called for.  The laid back character of the Scalas was completely gone with the Electra’s pulling them into a now engaging, emotional, complete presentation of sound.

The similar DNA of the two, (Beryllium IAL tweeter, 3rd generation “W” cone mid and bass drivers, yes the crossovers are different as are the “flower power” driven mid of the Utopia) can only benefit these two speakers working as one.
What surprised me too is how well the Pass Labs performed driving these two speakers.  Perhaps because there is so much more energy produced, the amp stays in Class A  much more than it did when I was running the Scalas alone at higher volume.  (Played together they need not be driven as loud to create such a satisfying and complete soundscape..)   This says as much about the Pass Labs amps as it does the Scala/Electra combination.  In my opinion, based on my experience, this is a phenomenal combination of great products, in which the whole betters the sum of its parts.  

I feel fortunate to have been able to experiment as such, and would advocate others to do the same.  You may be very surprised at the results as I was.

Focal speakers BE tweeters are typically 27mm (1.125"), like Dynaudio's esotar which is also 1.1". It's a little more directional than a typical 25mm tweeter, which generally leads to a less "airy" sound since you have less reflections.
At one time I ran a pseudo quadraphonic setup with four speakers. The speakers are wired to simulate quad by wiring them to utilize out of phase information. The details are probably available on line somewhere. It’s pretty cool. I also ran four speakers with the digital time delay unit I had for a while.
jamnov, congratulations on the exploration! It is terrific fun to explore/experiment with systems! You are doing a "stacked" speaker system variant, and with same brand speakers I'm sure it does sound very good. You have put many of the variables in your favor to have a good outcome.

Pretty amazing, eh, when you work from a consistent amplification on such setups. A real eye opener. Make sure you pay attention to aftermarket cables, including power cords. The system would love that stuff. If you have not yet done that, you have a lot of improvements to come, and you would not be close to your best sound yet.  :) 

While what you are doing is not considered by most to be a severely compromised audiophile setup, I get it. I have done similar things in the past, and the fact is that certain aspects of audiophile sound improve with such a setup while others diminish. It's a matter of taste which ones you prefer. 
What you have done is similar to a Line Source speaker, a popular genre of speaker that utilizes many drivers of various sizes. No wonder you feel the sound is great. 

What's nice is that you can swap back to the "purist" speaker setup with one or the other anytime you want. You have a variety of "best of all worlds" going at the moment. Kudos! Keep trying different amps, power cords, placement etc. because it all can be dialed in much more than you may suspect. If I had that setup I would try turning the smaller speakers around to fire backwards, just to see what the result would be. I would position the front baffle of the smaller speakers in line with the back of the larger speakers, so that it would be a quasi-dipole effect. I'll bet it would offer yet another interesting result. If I had the time and inclination I would try the smaller speakers turned backwards first outside of the larger, then inside of the larger speakers. Of course it's not "audiophile approved" system building, but there are no audiophile police who will knock at your door. :)

It's always great when you can experiment without cost. You also will learn much about the nuances/effects, good and bad, about such systems. You are one of the very few people who have the creativity and boldness to try such setups. It's obvious why you feel you are being rewarded. But, do not be shocked at this prediction; I suspect that over time (years) you may gravitate back toward a more purist approach with an even better single speaker and electronics. Perhaps you will turn into a hard-core panel speaker fan, as they have a lot of the openness that you are hearing. Lot's of directions to go! It's pure fun for me to see someone with an open mind and the will to be a system explorer. An audio system can be a play land that brings immense fun and joy. 

Glance at my Virtual System to see my enjoyment of variety and some alternative placement.