Baby started as a “proof of concept”, I wanted to investigate if the Dual Woofer system could work in a 2-way configuration. As mentioned in the
Special Woofer Design, the crucial dip frequency for the design depends on woofer size. This is the reason why I choose the 4 inch, long throw woofers. And the reason for a 1.5 inch tweeter, since the resonance frequency is lower than for a 1 inch standard tweeter. To save the tweeter from low frequencies, which they don't like (distortion, excess cone excursion and more) you prefer as high a crossover point as possible. But this pushes the same frequency up for the woofer as well... This is the dilemma, and it is a dilemma in a conventional 2-way speaker as well.
In order to be as close as possible to a point-source radiator, the tweeter is very close to the woofers, this is helpful for frequency response and stereo image. The cabinet was designed with no parallel surfaces to minimize standing wave problems. I wanted a small cabinet but fair bass power, and this combination suggests a bass reflex system, the woofers are also designed for this. Port tuning is conservative, I wanted to maintain a reasonable impulse response.
Baby is yet a prototype, but the distance to a finished product is quite short. I will work with cabinet details, with distance between the two cabinet bodies, and shape/thickness for the acoustic foam in between them. Distance between magnet of tweeter, and magnet of top woofer is another detail, can't be too close because of mutual magnet influence/disturbance. Measurements and sound are fine. Check the pictures, they say more than many words.