A 2.5-way using the low end reach and clean upper midrange of the Exodus Anarchy 6.5″ driver, this is tuned to about 28Hz, yet a very comfortable footprint and low profile. The Anarchy is paired with the SB Acoustics SB29RDC-C000-4.

Voted “Design I’d most like to have in my living room” at DIYChicago 2011

Box design and info

  • 2.5″ diameter port should be ~12-13 inches long.
  • 3″ diameter port should be ~18″ long
  • 1×7.5″ slot port should be ~18.5″ long (equivalent to ~3.1″ diameter)

Series Crossover

Bill of Materials

  • 25μF
  • 16μF
  • 14μF
  • 10μF
  • 4μF
  • (optional) 47μF
  • 1.2mH 14ga (.24Ω)
  • .39mH 14ga (.12Ω)
  • 2.7mH 16ga (.60Ω)
  • .91mH 18ga (.40Ω)
  • .33mH 18ga (.26Ω)
  • (optional) .5mH 20ga
  • 8Ω
  • 4Ω
  • 2.5Ω
  • (optional) 5Ω

Parallel Crossover

Bill of Materials

  • 15μF
  • 14μF
  • 12μF
  • 10μF
  • 4.5μF
  • (optional) 47μF
  • 1.2mH 14ga (.24Ω)
  • 3.6mH 16ga (.70Ω)
  • .3mH 16ga (.16Ω)
  • .36mH 18ga (.27Ω)
  • (optional) .5mH 20ga
  • 8Ω
  • 4Ω
  • 2.5Ω
  • (optional 2nd 8Ω)

Measured/modeled Response

Black is the series summed response, yellow is the parallel summed response.

Red/blue/pink are series individual driver response(s).

The dip at 3k is diffraction induced. This is measured without the chamfer and that improves in post-chamfer measurements.

And here’s what reversing the tweeter does, since some like to see that.

Impedance

This is the series crossover with a LRC to flatten impedance, otherwise it peaks up to about 12ohm in the 1200Hz-ish range, phase gets up to ~+20deg and -30deg at 400Hz and 2200Hz respectively. So rather benign either way. Solidly above 4ohm all the way. Below is uncorrected.

And the parallel crossover (corrected) impedance.