Okay, as I was playing through all of these 1x15's, I did happen to look over at my Phil Jones Bass 9B sitting in the corner, and I couldn't help but note that it is about the same size as the typical 1x15. So, just for kicks, I did a quick and dirty comparison to some of the 1x15's.
First off, the specs are 9 5" drivers, 8 ohm, 900w, 40 Hz to 15 kHz, 76 lbs, 18" x 20.5" x 17.5", and it is primarily intended to be used with the 6T top (but I just tried it on its own). My experience with PJB cabs has been that with SS power, they are real hogs, and need to be spanked hard (though they seem to like it

). With tube amplification, however, they tend to blossom with much less power (200w is plenty of tube power to get these cabs really going!). But this test was with the CA9, and I definitely had to crank the gain a bit more to get the 9B to put out as much as the 1x15's were dishing out. Once this was done, however, I had probably the most coherent midrange of the bunch, with a sense of attack that seemed just as strong on the lowest notes as it did throughout the mids. I do not believe the casters on the 9B are removable, and when it is sitting on its casters, it did not yield as strong of a low end response as the other cabs (which were sitting flat on the floor). However, if I laid it on its side, or sat it upside down, the low end was enhanced, and in this configuration, the 9B probably fell in the middle of the pack, to possibly on the lean side of the pack. The high end was very nice, and certainly all I would ever want as a fingerstyle player, though I could perhaps see where some slap/pop players might want a tad more sparkle - but really, the PJB cabs are more extended in the high frequencies than you'd expect from a cab without a tweeter. On the whole, the 9B was very articulate, very balanced and complex in the mids, punchy, smooth, and focused, but not as full/deep sounding as some of the 1x15's, and not as efficient, either.
Tom.