Is there measurement that correlates with cohesive/pinpoint imaging?

@tomic601 

Time and Phase....read what JA has to say about Vandersteen “imaging champs”....

Thanks for the helpful reply.  I just read JA's review of the Vandersteen Quatro Wood.  His measurements are interesting.   https://www.stereophile.com/content/vandersteen-quatro-wood-ct-loudspeaker-m5-hpa-monoblock-power-amplifier-loudspeaker

"Fig.5 shows the Vandersteen Quatro Wood CT's horizontal radiation pattern, normalized to the tweeter-axis response and plotted up to 45° to the speaker's sides rather than the usual 90°... The contour lines in this graph are impressively even, implying stable stereo imaging."   

"Like its predecessors, Vandersteen's Quatro Wood CT offers a true time-coincident output, due to the stepped-back sub-baffles for the upper-frequency drivers, the first-order crossover slopes, and the fact that all its drive-units are connected in positive acoustic polarity. Fig.9 shows the speaker's step response on the tweeter axis. The initial arrival is an almost textbook right-triangle shape, though the tweeter's output arrives slightly before that of the midrange unit. This confirms that the optimal axis will be 5° below the tweeter axis. Finally, the Quatro Wood CT's cumulative spectral-decay plot (fig.10) is impressively clean."

  

I do know that in the same room with the same equipment, my Omega single driver speakers had a much more coherent and precise image than my Klipsch Forte IIIs and a pair of Vienna Acoustics Mozarts that I compared a little.

@djones51   Thanks for the tips about these other speakers

I have the Dutch and Dutch 8c, I never really listened to single drivers at least since the 1970's when I didn't know that's what I had. The D& D are very coherent I guess because they do the crossover in DSP. 

And the really excellent designers use science and listening and a deep love of music to move the art forward- stereo is an illusion after all. There are some excellent recordings utilizing research and products coming out of work on head transfer function - Macy Gray and Amber Rubarth come to mind - both excellent and hyper frustrating at same time. I will post LP numbers if desired....