I am hoping I can get some help with my project. I’m retrofitting some old 2 way JBL boxes with new drivers and I’m at the stage of designing the new crossover. While learning how to use WinPCD and wondering how I’m going to compensate for the enclosure’s effects, I discovered Jeff Bagby’s Frequency Response Modeler Excel sheet. I also found Paul Carmody’s webpage for instructions on tracing graphs to make zma and frd files all the way to using the FRM Excel sheet to do just what I need.
Parts Express provided the zma and frd files for my woofer the Dayton Audio RS225P-8, and the webpage http://www.audiodevelopers.com/Referenc ... r=PE_DK%2F had them for my tweeter the Dayton Audio DC28F-8. I also have DATS V2 and can make my own zma files.
My first question is about Paul Carmody’s Step #5 instructions for creating the woofer’s simulated zma file using the FRM Excel sheet. Am I correct that you do not import and then modify the woofer’s anechoic zma file made by tracing or other means, but rather have the FRM Excel sheet create a completely new one from the data in the Impedance Model section?
My main problem and second question is about Paul’s Step #6. With all of my woofer and enclosure data filled in, all of the graphs look good except the top 2 in the Frequency Response Modeler section which just have straight horizontal lines. When I import the woofer’s frd file I get no change, still just straight horizontal lines in the top 2 graphs. What am I doing wrong?
My third question is about Paul’s Step #9 repeat for the tweeter. Do you have to complete the Impedance Model section with the tweeter’s Thiele/Small parameters to do the Minimum Phase Extractions?