I just bought one. I had to order one in order to hear it. Nobody stocks this thing around me. I decided to go ahead and get it after a job, which went like this :
I tested 3 cabs and 2 amps to find the best match for the gig where I needed clarity, not volume. I spent a lot of time geeking out on this over a couple days. At the time of the job I left the winners behind and carried the smallest stuff. And then left it in the car. I realized small and light is what I want, and I trust PJB to driver good tone.
yes I think this sounds very good for upright; better for upright than electric. The 5 inch drivers are basically full range speakers with excellent dispersion.
This little cab is the schlep king. Amazing. I'm happy to have it. It sounds good and clean, though not as Hifi as the big Brothers C4 C8, C9. This is natural given the size of the thing. Its response curve stops short of the lowest fundamentals which actually helps me on live upright bass amplification, because it reduces rumble. In perspective, You can hear a low B, but you won't quite feel it.
But the drivers are rugged. I'm not worried I'll blow them up. It gets loud enough for most of my work, which is "byo stage monitor" type amplification with mostly acoustic instruments around me- pit, pops, cocktail, dining, or almost any job with subs PA. I'm curious if I could stack two of these for loud jobs and get the spl of a 112 cab...