Thinking about the component cost involved in the Kii Three & BXT;
12 channels of amplification, a review of a hypex kit in this forum indicated $1,100 for 2 channels of 250 watts
So six needed = $6,600 of DIY
Six channel DSP $1250 x2= $2500.00
12 woofers/side, Morel 6" about $150x24= $3600
2 midranges $250
2 Tweeters, Morel 1 1/2" $340x2= $680
12 switch power supplies at $75= $900 x 2=$1,800
$15430 before;
DAC, Interface, wiring, extruded cabinet, hardware, assembly, programming....
Speaking from experience of putting together a playback system of;
24 midrange drivers
4 ribbon tweeters
Active crossovers with time alignment
4 Cardioid subwoofers with time alignment
Amplification of 2 channels of midrange, 2 of tweeters, four of subwoofers
The "ball park" above is close on a piecemeal basis.