ThePassive Crossover Designer 7 is a crossover simulation and speaker design tool built into an Excel spreadsheet. The design tool has now been expanded to include a box model, an impedance modeler, and a full active crossover design section for each driver than can be used along with the passive crossover features if desired. In addition to these features dozens of textbook crossover, electrical, and acoustical calculator tools are included as well.
Two versions of this program are available. One is optimized for Excel 97 - 2003, and the other is optimized for Excel 2007 - 2010. In both cases Analysis Toolpak must be installed and macros must be active for the program to function.
This spreadsheet will produce the frequency, phase and impedance response of 2 way, 2.5 Way standard and cascaded versions, and 3 way parallel systems, as well as 2 way series, 2.5 combined series/parallel designs, and can even be used to design 3 way series networks. It is designed to work with actual driver frequency and impedance data in the form of .frd and .zma/zda files which can be imported into the program.
It makes use of full x,y,z geometric location of the individual drive units and gives you a movable listening axis, both vertical and horizontal which will allow you to see the driver summation at almost any point in the front hemisphere of the speaker. This model now includes driver directivity, so off-axis simulations will also include directivity response variations as well. This proprietary tool offers very accurate simulations of the summed and individual driver's response at various axial locations.
The program has individual sections for woofer, tweeter, and midrange circuits, each with SPL and Impedance charts, as well as System charts that show summed SPL response, approximated power response, phase response, system impedance, and crossover transfer functions. There is a section for system input impedance equalization also.
Other features include - options for two woofers, or two midranges, and either wired in series or parallel, automatic calculation of L-Pads, Zobels and series RLC compensation circuits at the click of a button, user selectable built-in or imported Target responses that are overlaid with the driver's response in each section. And all crossover values can be continuously changed via "spinners" with the response will changing in real-time on the charts, allowing for quick curve-fitting of the response or impedance curves.
As mentioned above, the program includes an accurate box design tool with the ability to model the response of both vented and sealed systems. This add-in includes a unique and proprietary impedance modeler that will accurately model the impedance of the woofer in the box used and allow you to use this impedance curve in the crossover design section if desired. In addition, an active crossover section is included that contains high and low pass slopes up to eighth order, five band parametric equalizer (for each section), Linkwitz Transform, and level and delay adjustments. This section can be used with the box model to design subwoofers using active EQ and filters.
The program includes the ability to save out all individual driver, crossover (active or passive), and system SPL and Impedance responses to frd and zma files that can be used in other software. It has the ability to print or save charts, and a special system summary print-out page for your project. Included are Pop-up parts layout schematics for each crossover section. And finally, it also contains the ability to save all session data to very small files that can be imported again later thereby resetting all settings in the file to match the previous session or project. This gives you the ability to create a library of crossover designs while taking up very little space on your drive.
Changes for Passive Crossover Designer Version 7.0
The new open view of the file will show column and row headers, sheet tabs, and formula bar. The ability to switch to a full-screen view with these features hidden is still present by clicking the "Full View" button under the Chart Manager.
This version offers the ability to save the file with all data loaded under a new name and be able to reopen the file with the project intact. Simply click on "save as" in Excel, and give it a new name for your project. The spreadsheet will compress and save containing all data including frd and zma file data. When the file is reopened, the project will be exactly as it was when filed. (Files saved in this way will about 5mB in size)
Closing the file will no longer shut down the Excel application. All other open files will remain open.
Removed the System Description page. This page was causing too many issues with screen updating in Excel 2007 and was being used by too few users to justify maintaining it.
Built all of the old schematics and crossover layout pictures into the program rather than external and accessible through hyperlinks. There are no longer additional file folders that need to accompany the program to view these layouts. The buttons to access these layouts are in each driver section button grouping.
Added the ability to import second woofer and second midrange frequency response and impedance data files, so five different drivers can be imported if desired. (Note: If, however, you wish to model two woofers or two midranges and do not want to import a second set of data, that is OK, as the program will automatically use the original data as it did before as a default. The ability to import the second set of data is under the selection for two woofers and two midranges and is only an option to be used as desired. This allows you to import two different diffraction responses for drivers in an MTM, for example. Or you can import two completely different drivers with different frd and zma file if desired as well.)
Changed the Z-offset convention to be negative if the acoustic center is "behind" the zero plane, as in the case of the woofer's acoustic center being behind the tweeter. (Note: All .csp or saved project files earlier than version 7 will be automatically be changed to the negative of the stored value when imported. Version 7 files will not be changed but will remain exactly as saved.)
Corrected a problem in the vertical axis adjustment. It was originally upside down. This has been fixed. Now, if you set the woofer to be -.150 for a Y offset and set the vertical axis to -.150, for example, you will be aligned with the minimum phase axis of the woofer again and the phase will show no excess delay, as it should.
Refined the driver directivity and power response approximation models for greater accuracy.
Removed the separate hidden phase graph (used in earlier versions) since a dedicated phase chart can be printed and saved from the main graph's settings now.
Added buttons to remove the woofer or the tweeter (or both) from the simulation if desired for greater versatility. This can allow for modeling of single driver systems on the main graph, or to allow for simply modeling a woofer or tweeter's response individually on the main graph if desired.
Added special buttons to compress all calculations or to re-expand the calculations, if desired. (Note: when saving the file, it will compress the calculation automatically. If you wish to continue working in the same project you must click the "Expand" button to restore the program.)
Added a button to unprotect the main page of the file for better chart management. This was a tough decision to make because when the page is unprotected it is possible to inadvertently make other changes that would break or alter the program's function. Because of this nearly all other function buttons will reset the protection automatically. However, while unprotected you can select a chart, view the value for a given point, and even change the scale, line weight, or line color, etc. (Note: The end-user is responsible for all changes made to the program while the main page is unprotected.)
Made the textbook calculators more accessible by adding button to each to the button group in the Woofer, Tweeter, and Midrange sections.
Added Pop-up warning boxes for you to confirm your actions when clearing the crossovers or resetting the project. This ensures that you will not clear what you are working on accidentally.
There is an additional download available that includes a 35 page User Guide in pdf file format and several sample files that can be imported to demonstrate the programs features. This User Guide does not include Version 7 updates, but it is still helpful in understanding the program and providing sample projects to experiment with. A quick guide is now built into Version 7, so there is no additional download for that.