Hi Cubo,
thanks for sharing your plan! i‘ve recently built what i would call a „light“ version of the cubo15.
to put it on a tricycle, i‘ve used 12mm birch multiplex and left out any piece that was (in my view) not necessary to the mouth of the horn. also, i had to make it only 59,9cm wide, so it would fit the frame. i chose the cubo15 design since i am a big fan of the KISS rule, and the designs support of many different drivers- i thought if it can handle different drivers, it could handle my messing around with it, as well.
my cabinet is driven by a eminence kappa 15A, which i already had on hand. i was concerned if the lack of braces would result in resonance from the body. but since the speaker is powered by a tiny class D amp board, there is less than 100 watts going in, so there is no problem before the amp starts to clip audibly.
in case anyone is curious, the amp is a tinysine 50+50+100W with bluetooth and dsp, which i am running active 3 way. the top is built after a plan from celestion, again using drivers i had. currently, the dsp is only doing crossover at 90 and 4k hertz, but i plan to do some measuring and correct phase and frequency response. crossover points and gain reduction (something like -10db for mid and -17db for hf) were chosen by listening to different music which i use regulary to set up sound. i am happy for any suggestions on how to improve
the (almost) finished cabinet can be seen in my profile pic- i just need to add a speakon connector in the back, so the cable won’t come out the mouth, and glue & screw the top plate. so far, i am pretty happy with the result!
cheers! J.