
Explore loudspeaker crossover design by selecting resistors, capacitors, and inductors, shaping frequency response with filters, modeling in XSim, and testing prototypes in enclosures.
Explore conductor types for audio inductors, comparing iron core and air core inductors, noting resistance impacts on crossover frequency response and the trade-offs with wire gauge and price.
Use a series notch filter in the loudspeaker crossover to flatten the impedance peak near resonance, broadening the notch with capacitor, inductor, and resistor adjustments for attenuation.
Design a two-way bass-reflex bookshelf crossover using a peerless mid busdriver and a Rayleigh tweeter; set crossover points near 1.5 kHz for the first driver and 3.4 kHz for tweeter.
Measure the far-field frequency responses of the tweeter and mid bass, apply the Hilbert transform to compute the full response, then design the crossover and align acoustical centers with delay.
Design a crossover for an mtm loudspeaker, implementing third-order filters for the tweeter and second-order for the bass, and applying a parallel notch to refine phase and frequency alignment.
Explore a two-way bass reflex enclosure, 16 liters, tuned to 51 hertz, and how offsetting the tweeter reduces diffraction. Learn crossover design from in-room measurements and 2–3 kilohertz cues.
Learn how ladder delay networks adjust the phase of loudspeaker crossovers without altering the frequency response. Focus on first-order designs and practical component relationships.
Design a three-way crossover for a bookshelf bass-reflex enclosure, aligning woofer, midrange, and tweeter using measurements to set acoustical centers, delays, and crossover points.
Check component voltage and power requirements with a FEMA tool, then select film capacitors for high voltage or electrolytics for cost efficiency in the crossover, and simulate 50 watts.
Build the bass crossover board by mounting capacitors and inductors, soldering connections, and securing components with zip ties while aligning plus and ground to the amplifier.
Design you own speaker crossover
This course is the last piece in the loudspeaker design process. You will learn how to use the FRD and ZMA files (check Acoustics 201 course) to design 2-way and 3-way crossovers. These designs will be done in XSim which is a free application. Crossover design, while it does have some general guidelines, it's unique for every crossover. For this reason, 5 different types of enclosures have been built for this course : two 2-way bass reflex bookshelf speakers, a 3-way bass reflex, a sealed MTM and a 3-way bass reflex floorstanding speaker with dual woofers. This way you will get a better understanding on how the process works. It takes not only knowledge, but also intuition and experience when designing a crossover.
Specific circuits for crossover design
Besides the basic filtering for speakers (1st order, 2nd order, etc), there are other circuits which are implemented to correct the frequency and the phase response of the system. Since we have 5 examples to play with, we have enough crossover projects to go through most of these in a practical way. To mention some of the circuits : impedance equalization circuit, attenuation pad, baffle step compensation, ladder delay network, notch filter, and more.
Testing the new crossovers
Designing a crossover on your computer is convenient but we will also test it out. I have a large amount of electrical components, capacitors, inductors and resistors, from small to large values. After we design the crossover in XSim, we will assemble a prototype crossover and check how it measures and how it sounds. Some tips and tricks on how to make your life easier and what to avoid when building a prototype.
Building a crossover network
Building a crossover network will require some handy work. You will need to be aware of the size and material of the board, how and where you place your components. What will you use to fix the components to the board. How to make sure the components won't rattle about. Unavoidably you will acquire some basic soldering skills as well.
At the end of this course, and by taking the previous 2 courses as well, you will be able to fully design from scratch your own multi-way loudspeaker.