Digital Crossovers

In the world of DIY Audio, building good passive/active crossovers isn't for the faint-hearted!

Passive/Active crossover

From the filter simulations to building & assembling the analog crossovers, expect many prototypes to get it right. Why? For one, because the software package you may be using to provide acoustic modeling of an enclosure & driver combo is only a model. In other words, an estimation based on math equations. No matter how you look at it, it is not the real world where an element not included in your "model" will most likely modify the response. Your choice of drivers will also interact with the crossover components/filter configuration, making it harder to simulate the system performance. In the end, any experienced loudspeaker builder will agree that there will always be some unknown element that software simulation doesn't cover. The trial & error with different configurations then wins hands down over the pretty software simulations. So get yourself ready for an extensive set of passive components, multiple PCB revision and time to brush up your electronic theories (basic & advanced). Quite a daunting task!

Digital crossovers

Coming to the picture are Digital Signal Processors (DSP) performing the crossover filtering tasks required for active powered speakers. With their great flexibility, ease of use and accurate response, controlling the parameters of a crossover becomes a child's play. A digital signal processor uses cascaded filter banks (IIR or FIR) to provide the processing you need. Forget about electronic design or PCB prototyping with our products. miniDSP kit, a low cost  firmware upgradeable module,  breaks the misconception of Digital Signal Processors (DSP) being expensive.

Screenshot of miniDSP 2way Crossover control panel

A miniDSP kit, a small 4 channel amplifier and off you go prototyping your ideas. Loudspeaker prototyping finally getting back to audio, not writting code or understanding math equations.

miniDSP + 2way plug-in configuration for Stereo 2 way system

Time alignment

In a loudspeaker cabinet, time alignment of each driver is paramount to proper wavefront reconstruction. Think of a tweeter and woofer, mounted to the front of your enclosure,  their respective acoustic center will obviously be offset in space, so in time. The end result will be comb-filtering among other things. (Frequency response not uniform)

By combining time alignment along with the phase relationship from the crossovers, miniDSP kits can make acoustical outputs of adjacent loudspeakers to become coherent.One can easily prototype many configurations by modifying delay and crossover settings with a few mouse clicks.

Over are the days of passive filter prototyping, may the DSP fun begin!

Where to next? 

- Looking for a 2 way configuration? Have a look here.

- Looking for a 3 or 4way configuration? Have a look here.