I started this design using the Passive Crossover Designer (PCD) by Jeff Bagby. It's an Excel spreadsheat available at the FRD Consortium. It can import measurement files directly, including the phase, so determining the relative acoustic offset is not necessary if the files have the measured phase. After a number of iterations of crossover points and slopes I settled on one that was then used as the starting point in CALSOD since it can model more complex crossovers and has a full optimizer. As I write this, however, Jeff is adding extra functionality, including more complex crossover topologies.
Next I set up the CALSOD file with the starting values taken from the PCD. After experimenting with topology changes, I settled on the design presented here, a 2nd Order Linkwitz-Riley for both crossover points (Fc). The Fc frequencies are 300Hz and 3,000Hz.
For the graph on the right, Yellow is the on-axis summed response. Red is the predicted power response, though it does not take the individual driver off-axis responses into account (yet).
This design is free for personal use only.
| Raw Driver Frequency Response Plots
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Final Crossover (CALSOD Exports)
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System Target and Predicted Frequency Responses and Impedance Magnitude and Phase
