121 wedge/top cab help needed

Im working on this design but am unsure of some of the figures and hoping that someone can help me.

I got the initial measurements from a CS121 (concert systems) i spoke to them and was told the logic systems made the boxes for them.

Im using WinISD online and a B&C 12NDL76 and DE250 and this is what I've come up with





I think the box volume is 52L and tuned to 73Hz, using the paramiter from the B&C website
Vas :- 73
Qts :- 0.20
Fs   :- 50Hz

I know the port length is wrong I think it should be 8.146mm not 115mm as on the plan.

If anyone can point out any rookie errors it would be appreciated.

re. triangular ports, you'd just calculate as if they were square, working out the equivalent dimensions of a square port and using these in winisd.

i seem to remember someone mentioning that a triangular port can be viewed as very slightly smaller than it's round/square equivalent. this is because the sharp angled corners have higher resistance/losses than a round/square port would.

can't really comment on tuning decisions, as i've only built one pair of monitors. i used B&C 12HPL76 and B&C DE250, around 58litres (not including port, driver, horn etc) tuned to 60hz. i've not measured impedance plots or freq response, so im not sure whether that's the true tuning, but i'm happy with them

Just to complicate things even more---Are you intending to use them as a multirole cabinet?

will do ceharden just got to get the drivers.

I've used a 40 degree angle on both side as per the cab Im cloning.
The cabs im cloning Ive used as FOH and and wedge (more as wedges) and been really impressed.
I will have a play with the angles and see what happens
cheers
robbo

what do you mean by acoustic compensators?
I've looked at the mentioned products but don't understand

accoustic compensators = blocks of wood / steel poles to change the angle of the box so its pointing at the artists ears!