Tonight I spent some time in Google Sketchup to sketch up my speakers. This is my ever lasting project and every bit helps to keep myself motivated ! I’m uncertain about the colors and the finish to use as it will all be MDF but the current render gives a good idea.

The project is a 4 way active system; with 2 subs, lower voice, upper voice and tweeter. I have completed an analog crossover but I’m tempted to replace it with a variant of the DSP board I published earlier. The system will feature the ability to turn on when “detecting audio” or with 12v triggers. An output trigger (also 12v) will be present and independent of the input trigger; it will turn on with the “speaker” so I can power/trigger other equipment.

The two subs will likely be a Class-D amplifier based on a TAS5630 while the voices will be based on a LME49811 ‘chip amp’. I will likely reuse my (modified) JLH Class-A for the tweeter, while overkill.

One thing I’m very uncertain is where to unbalance the signal. I’m currently doing it before the crossover (and therefor before the amplifiers) since it’s my understanding that matching parts is critical and very hard when purchasing small quantities.