
While the S16 provides smooth directivity, they are lacking rear radiation. In this iteration I want real dipole radiation front and back, and uniform to very high frequencies. This can only be done with extemely short front-to-back distance.
Design
The "tweeters" used areTandBand 3" full-range. They allow three things to happen:
- Dipole peak to occur very high in the frequency range, allowing constant directivity
- Very open rear chamber for good rear frequency response
- Low crossover frequency.
Measurements
The directivity plot was measured indoor so there is room for improvement when I take it for outside measurement later.
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These are respectable uniform dipolar radiation, impossible to achieve with traditional methods like back to back dome tweeters.
The tradeoff is high frequency resolution of the 3" fullrange drivers.