Yes, i build my BR boxes myself.

I used as reference the small BR fostex recommended enclosure, keeeping the volume(9L) and cross sectional area, but i "customized" them with rounded walls (Sonus Faber style !).Hard time to do this, but in fact i'm quite satisfied by the AESTHETIC result.

Then i tuned the port using Bassbox software, around 70-75Hz.

I used MDF 19mm with 3 coats of blackson (car damping painting).

Plus fiber layer i'm still trying to adjust.

At that time, i had never heard of MJ KIng, Bob Brines or TQWT...

That why i'm trying to get a better result, using modern designing theory !

55Hz would be nice !