Martin Logan on it's side for center channel ??

Hi OP:

The thing about a traditional ESL is that they are designed for wide horizontal dispersion + narrow vertical. If you turn the speaker around 90 degrees you’ll get a whole different story. Now you’ll be narrow horizontal and wide vertical. That’s just with the ESL panel. My point to this is, what makes an ESL sound great vertically hurts you horizontally.

The woofer (or woofer + passive radiator?) was clearly meant to be reinforced by the floor. Also, this will look weird. :D

I mean, sure if you have a 3rd ESL and want to do it just cause then do it just cause. If it were my system I would not expect it to be that great, so why bother wiht an ESL in the middle to begin with?

You should notice that the center channels ML makes are short (left to right) and augmented by a tweeter for a reason.l

I'm  thinking the Logan centers have drivers added to them because the electro panels are too small ???

OP: Has more to do with getting the proper dispersion and listening angle. :)

Do a little research into the angle of listening (dispersion) vs. the size of the moving diaphragm and that will answer a lot of your questions and explain my recommendations.

Of course, nothing wrong with you learning by doing! :D

Should also consider, if ESL’s worked horizontally, why aren’t they all horizontal? :) The answer is, again, the dimensions of the diaphragm.

If you have 2 ESL's already, and want to experiment, go ahead and turn them 90 degrees and tell us what you find.