I realised if I do the talk I better walk as well
This is the setup with the horn set against a back wall. XTZ Room Analyser II connected to my macbook (with WinXP in Bootcamp). Microphone is center line about 70 cm in front of horn opening.
The driver in the back is the Beyma G320 (Fr= 52 Hz and Qes= 0.2) built to be a horn driver. The other is a Fane Crescendo 80W Silmilar Fr but a Qes of about 0.5
Starting with the Beyma horn driver With no reflector(green) and then adding the bisector in front of the driver (blue),not much happens below 1 kHz
Adding corner reflectos add some dB jsute below 1 kHz and a huge bump around 2 kHz
Adding both the bisecting reflector and the corner reflectors, brings us back at square one!
Here we have the impedance plot Dayton Woofer Tester 3. System resonance at 77 Hz and medium Q value of 0.8 Note the gently sloping response below 200 Hz
Turning to the Fane driver with a higher Q adding a bisector. Note the hump in the bass just above the HP. Here there is about 4 dB added both at 400 and 900 Hz by the reflectors
Then adding both (I missed measuring just the corner reflector) Either some few dB added 200-800 Hz by te reflectors (blue) or back to square one
Impedance plot show a Fr 10 Hz lower and higher Q of 1.4
Tossing in a Vintage driver with a Fr of 30 Hz Qes of 0.4 and Vas of 300 Liters! The setup is different the green line is tha Beyma and the green is the vintage driver that is a theoretical mass rollof of 150 Hz but a practial one is this case of 1200 Hz
The images are cropped for some reason.
The system with this driver has a Fr of 67 Hz and a Q of 1.4 suggesting having a low Fr higher Q driver might be better than adding ports and stuff. I also note that Klipsh original driver is far from the classical horn driver of say 50 Hz an a Qes of 0.2