Mark Audio CHP-70 BR cabinet options

Hello! I'm new to full range speakers and am considering building a pair of bookshelf FR speakers using the CHP70. I see a couple of designs available from the Mark Audio website and madisound but hoping for direction while I choose which to try. Links here:
CHP-70.2 vented box standmount
and
Fenlon 70CHP:
and

Golden Ratio vented box

I realize the low end of a small driver is limited but I'm hoping for "as much low-end" as possible while still sounding good. So I assume that puts the GR box would be best with its 11L volume.
Regarding the port, is there a reason that a port would be on the baffle rather than back of the box?

Thanks for any comments!
 
Mike beat me to my box. CGR is 9 litres.

Note that the CHP70 shipping has a shelved down hi end. The intent was a vintage top end. If you can live with that the are really good everywhere else.

Note: I have 1 set of demo CHP-70.2eN (don’t know where CHP70.3 came from, i could guess).

dave
 
You can’t PM me ever, i have PMs turned off. I did get your email, the reply (sent twice) with it being delayed. (@tubestore domain)

Something to do with the server that handles your mail, i have the same issues with my driver who lives across the street.

dave
 
I have a pair of CHP 70s in slim GRs and have never felt (or heard) the need for BSC. I have typically had it close to a wall behind it, so that can make a difference. I'd suggest building and then listening to it for a few hundred hours before deciding on BSC. If you don't already know, it's extremely important to break them in per the manufacturer.