I'm genuinely impressed by the workmanship in the cabinet; CNC certainly helps take the slop out, I'd wager!
But the design engineering is very good, too. I was most intrigued to see if the side openings would solve the problem of "what is the back wall going to be this week." The ports are probably about the same size overall as you'd get out of an oval-back 2x12, but they're situated differently. They do seem to help with the issue I hoped they would: the cabinet is much less picky about where it sits or what is behind it. That's good.The sweet spot is nice and wide: the beaminess I've heard in other cabinets seems to be less of a problem with this, at least in the very high end. I don't know how much of that is speakers, how much is the vertical orientation, or how much is the cabinet's unique porting. The high mids are still a bit beamy, but you seem to be hearing more of what the audience hears with this cabinet if you just off axis a little. Even so, I tried a set of Jay Mitchell's "diffusion donuts" that I had modified quite a bit, and liked the consistency of response side-to-side even better.
I found myself wondering if a port could be put in the top of the cabinet for those times I'm standing right in front of the thing. Instead, I turned it on its side: voila! Very nice. It doesn't seem to care that the ports near the floor are partly blocked...the inch or so that the feet on the side provide seem to provide enough that the port resonance isn't affected much audibly, but there must be some effect on the way the sound is spread. I definitely prefer the sound of the cabinet in vertical orientation. Here's at least part of the reason why:
I like to mix and match speakers, trying to find a combination where each speaker overcomes the weaknesses of the other. For testing, I loaded both cabinets with a Celestion G12-65 Reissue and a Scumnico 65W since I have two of each. So they theoretically should have sounded very similar. One thing the vertical orientation does is to allow this integration to happen more seamlessly. In a horizontal design, the highs in particular tend to segregate themselves horizontally, so that moving a few degrees off axis in either direction gets you hearing one speaker, but not the other. When the speakers are oriented vertically, the sound melds much better between the speakers. It sounds like one speaker, although standing nearby you'll hear more of the one on top. But when you're out in front more, the effect is that of one seamlessly integrated speaker no matter what your angle to the cabinet front is.
Most interesting so far is the Forte cabinet's affect on the overall tone. The Burt cabinet I would describe as WARM. There is a nice woody resonance to it, and perhaps because of the floating baffles the impact of notes is softened a bit. But the Forte cabinet is much more forward sounding: there is something about the mids (1kHz-2kHz ish?) that is pushed up front quite a bit more prominently. Notes tend to feed back more easily, even using the same speakers. And it doesn't, as far as I can tell, have anything to do with the side ports versus rear: I can hear the effect most listening to the cabinets pointed straight at me. The effect is that the Burt cabinet is, by comparison, warmer and gentler sounding in some ways. But that doesn't mean the Forte is cold: it just has more projection and cut in some very good ways. The Burt cabinet sounds more polite for playing in your house, but in a band context I can easily see where the Forte might find...it's forte. Or you simply choose a different speaker that plays to the enhanced midrange of the Forte.
I am very pleased with the cabinet. It looks and sounds great, and when you take the back panel off and look inside to see what good engineering can do with really tight tolerance cuts and precise machining of the internal structures, you appreciate it even more. It's built to last, to be as light as possible while still delivering a heavyweight sound, and to me it delivers.
