For this competition, I’ve choose to design a sub with high level capability, something that can compete with an F218 Funktion One in terms of SPL and low response. Yes, it is a great challenge with a speaker which has a Qes of 0.496, but I like challenges.
I’ve designed an hybrid horn/reflex. I’ve already built this type of cabinet: They sound right with very high level sound pressure, great dynamic. A lot of people in France love them and they are easy to build.
I use software like Akabak, Hornresp to make simulations. I well know them, they are quite accurate if properly set.
The sensitivity is 104.5dB 1w (2 volts 4 ohms) @ 1m
Theoretical maximum continuous SPL: 137.5dB and 143.5dB peak
Low response:
One cabinet :
43Hz -3dB
39Hz -6dB
35Hz -10dB
Four cabinets :
38Hz -3dB
34Hz -6dB
29Hz -10dB
Recommended high pass filter: 34Hz 24dB/oct Butterworth
Ports are properly sized to not hear air noise at high pressure level.
