Practically 25Hz response in eigth space! Its because I ended up adding a little more length to it while keeping mouth area small to get lowest Fc. Excursion is also lower now down to a lower frequency than before, more power handling and SPL :D

A linkwitz riley crossover which is -6db at the crossover point, at 70Hz will get rid of the rising response curve and make it completely flat.

Hornresp doesn't predice room nodes of course (only boundry reinforcement as extension of length and mouth area) so I might get more bass than in the above graph.

2.80m long, 2000cm^2 mouth. Close approximation of real exponential flare (areas correct for expo). Schematic:

All wood is MDF, 25mm thick (=1"). External dimensions inc wood thickness is 100cm deep, 109.25cm high, and 53cm wide. Compact by my book :D

The 18LW1400 has a very stiff cone so it wont self destruct from throat pressure like some drivers do. Bassmaxx have also done work with the 18LW1400 and it survived all the tests, while other drivers the cones just crush (eg: Aura 1808). I think they are going to use the 18LW1400 in the new Bassmaxx B3.

As I said before JBL 2242, Eminence Magnum 18LF and Omega 18 also have the same response curve in this horn so they could be used too.

Adrian