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Ok, we all thought about it when we started building our own speakers. Many of us may have even done it. What is "it"? It's choosing some drivers and paying for a "LEAP" designed crossover. Then, without much other than a lot of faith, we buy the required parts and build it. We like to think we've "tweaked" it a bit to our likings, but the basic character of the speaker was determined by whoever plugged the numbers into LEAP, Calsod, SpeakEasy, or whatever |
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The purpose of this is not to question, analyze, or otherwise discuss the quality of computer-optimized designs you might receive (for a fee) from those people and businesses that offer these services. This page shows the first "suggested" crossover I am publishing for those who are interested in designing their own enclosure and simply need a good starting point for a crossover. Each "suggested" crossover I will be posting is particular for a set of drivers at a particular crossover frequency. Due to the volume of e-mail I receive, I won't be able to respond to any request regarding "substituting" drivers . These crossovers will only work with the drivers specified and you should not assume that any other driver, even in the same "line" from the same manufacturer will work. Also, don't ask about adding additional drivers. The "suggested" crossovers, when used as specified, can form the basis for a speaker of your design, so if you want to make any changes, good luck... but you're on your own. That said, feel free to request a suggested crossover for a particular set of drivers. If I have the drivers available, I'll be happy to plug their data into Calsod and post a "suggested" crossover. If some of you are wondering why I'll accept suggestions but not substitutions, it's because any change in drivers, whether it's substituting a driver, adding an additional driver, or whatever requires the same process -- a complete redesign of the crossover from scratch. Also, you'll notice that I tend to use "amp-side" attenuation in my crossovers. These tend to produce better impedance profiles and smaller component values (making the crossovers cheaper to build). Unfortunately, it makes them much harder to "tweak", since changing the series resistor in the highpass sections of the crossovers requires you to change all the other values as well. I apologize to you consummate tweaks, but you'll thank me for all the money this can save by using smaller inductors and capacitors (especially if you want to use large gauge inductors or expensive, premium capacitors.) |
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The first crossover I'm posting is accompanied by actual measurements, to verify the accuracy of the modeling process. I will not be doing this in the future (unless I happen to build a box in which to test the crossover). I did it in this first case to verify the accuracy of the computer-optimized crossover. To develop all of crossover, I tested the half-space frequency response of each driver on an "infinite baffle" and then imported the data into Calsod. Using Calsod, I modeled the data for a suggested baffle width and woofer alignment. Also, please note that I provide the acoustic rolloff rates of each driver. Please do not confuse this with the electrical rolloff rate (order) of the crossover topology. |
