What I'm hearing from 3677s in place of Theatre 4???

As an experiment I put the JBL garage sale surrounds in the system in place of the 4's. Also am using the Outlaw receiver while I re-do the Paramours.
Keep in mind that the 3677's have the 2226J woofers from the sale and Eminence 1.6 crossovers with C1 removed and the tweeter resistor/cap network. For those unfamiliar, the 3677 is a 4.5 cu ft dual port enclosure meant to hang from the sidewalls of Cinemas.
The size is about the same as the Pro 4 and I'm not liking what I'm hearing.
The bass, of course, is good but female vocals and upper register of piano sound tinny/transistory. No sparkle to the highs, piano doesn't sound like piano.
Full orchestral is very congested/constricted. The receiver is better, way better than that with the Theatre 4's.
I turned them around so they face the corners and play directly into the rolls of insulation I have in the corners. To simulate their performance as 7's.
Gee. That sounds kinda muffled.
This is scary. Is the 4Pi Pro really the same size box? Does the JBL not go as high as the Eminence Delta? why does the upper mids and highs sound so bad?



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