I think 80HZ best but both nice horns. Could live with either.

I'd be interested in hearing how room size affects the sound of these huge horns. I can't imagine a smaller room would be as effective for transmitting the lower frequencies. Great machine and excellent sound from both of them!

I vote for the 80hz

the bigger Of course lower but you're losing that mid range and top end. a approach you could take I've done it with speakers you can put a bullet in the horn like a teardrop, and how wide it is to the sides of the horn on the horizontal you don't need to go in the vertical will determine frequency response, another approach what I haven't tried it might do the same thing is to put a smaller horn in? you are increasing the surface area what is good and having another horn will give you the top frequencies as well maybe an inch throat opening, it might work better and then the bullet. I'd say you want it fairly close to the sides of the major horn maybe quarter of an inch, you need to experiment and just three brackets and screw it from the outside of the horn. When experimenting you could place it on a stand and move it in and out because that will have a bearing as well on frequency response and the size as well. I don't think you need to make the horn or bullet long about 3-5 inches. it should work very well when you've got it right