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

Not this week maybe never.

, at least the efficiency should be in similar range.


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Im running 91 sens FR with SEAS W18E001 dual each channel and having success, But best to cross the W18  low, say 1500hz. This adds a  bass floor to the 4,5 or 6.5 inch FR. 
Now the FR at 97db, the W18's at 87db won;t work. 
So agree, sens has to be at least close

I'm about to go SET amp  and dump the Defy7,,so I might have to dump the W18's and find a  higher sens bass unit to go with the Voxativ 8 AC1A

But I'll bet the non-casual listener, who enjoys sonic accuracy, would be shocked to hear an acoustically well-set-up quality two channel speaker compared to a mish-mash of various speakers channeled together when volume matched. It's all good; just keep listening!

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No doubt about it, Stacking old Advents, Acoustic Research, Rat Shak's sounds pretty awaesome,,,,TILL

A master shooter likea   Voxativ AC1A with 97db walks into the saloon shooting down all these ~~Frankenstein~~ speakers,, as Adam over at madisound  labeled my Seas W18E001 duals  paired with 91db FR ~~monster~ aka The Frankenstein,,But I am loving this sound vs the Thors with the seas Millennium tweeter. \
= Mix N match works great,, until a  REAl DEAL highs ens super high tech walks into town and blows away all these  Frankensteins,,,lol

We did that in college. Nothing like two pairs of JBL driven by 60 watts of Kenwood and Pioneer (using only the highest quality lamp cord, it should go without saying) in a 8x15 foot dorm room. Totally recreates with perfect fidelity the experience of high sound pressure levels.

Has anyone seen the Tekton "The perfect Set"? It has a few tweeters in each cabinet!

But if you read the white paper on the design behind this, it is not just sticking a few tweeters in the cabinet.

They are all acting as one driver. In other words, lobing, phase, cancellation, etc, are all taken into consideration by Eric Alexander in the placement and crossover design.

He has several very informative vids on YT explaining the reason for the design. And again, it is not just sticking a bunch of tweeters in a cabinet. 

I will reiterate what I said months ago, the chances of getting a good, flat frequency response, with phase not becoming any worse than one pair of the speakers being used, with no weird new, cancelations, standing waves, increased dips or bumps in the frequency response, or other unpredictable results, are not good. 

If one likes the result, that is fine.  Maybe you like whatever frequency aberrations are caused by multiple drivers operating at the same frequencies.