PCB DIY
Digital Audio Crossovers
In the world of DIY Audio, building good passive loudspeaker crossovers isn’t for the faint-hearted!
From the filter simulations to building & assembling the crossovers, there will most likely be more than one revision 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, not the real world where, for example, an odd reflection inside the enclosure may 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 would 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 you better get yourself ready with an extensive set of passive components, build multiple PCB’s, start learning electronic theories (basic & advanced) and try out your luck to fit the previously simulated configuration. Quite a daunting task!
Digital crossovers
Coming to the picture are digital crossovers such as the miniDSP kit. 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.
If you ever thought of building an active bi/tri/quad-amped loudspeaker , you must have also realized how complex of a task it is. 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.
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.
Processed Active loudspeakers
miniDSP kits along with our soon to be released miniPower modules will be the perfect fit for DIYers in need of an easy solution to prototype small active loudspeakers. Neatly tucked inside the enclosure, the DSP + all digital amplifier combo will provide flexibility and useability DIYers always looked for.
Over are the days of passive filter prototyping, may the DSP fun begin!
For more information, check us out at miniDSP.com
About the Author
Tony is the co-founder of miniDSP, a company dedicated to digital signal processing for audio applications. Besides his passion for audio, electronics and music, Tony loves traveling through out Asia Pacific, discovering one culture at a time with what the world has to offer.
PCB-Printed Circuit Board-DIY-PART I-Exposure & Developing
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