Armageddon Audio Transducers

Specifications

• Drivers
  • Tweeters: Vifa D25AG-35-06 1" aluminum dome (upgraded to Focal TC90Tdx 1" Ti oxide dome)
  • Midranges: Vifa P13WH 5" polypropylene cone
  • Woofers: Audio Concepts AC10 10" polypropylene cone
• Enclosures
  • HF enclosure: Approximately 1/4 cubic foot volume with 2" port tuned to around 70Hz. 3/4" MDF walls, no internal bracing (unnecessary).
  • Woofer enclosures: Approximately 2.5 cubic foot volume with 4" port tuned to around 31Hz. 1.5" MDF walls, no internal bracing (not really necessary, but mainly because it would have been too much of a hassle).
  • Electrical bulkheads: 1/4" aluminum plate with banana jacks, sealed with silicone caulk.
• Crossover
  • Active 4th order Linkwitz-Riley, at 280Hz and 2800Hz.
  • 2nd order high pass in the woofer section designed as part of a 6th-order sub-Chebyshev tuning for the woofer response. Theoretical acoustic cutoff frequency f3 = 34 Hz.
  • Option to change jumpers, thus changing the normal 280Hz high-pass filter on the midranges to a "booster" filter designed as part of a 6th order Chebyshev tuning. This allows stand-alone operation of the HF enclosures, theoretically down to 50 Hz. I doubt I'm currently getting that partly due to the 1.5" port, partly because the port hasn't been tuned empirically yet.
  • Burr Brown OPA-2604 dual BiFET audio op-amps (upgraded to OPA-2134), 1% metal film resistors, 2% polypropylene capacitors.
  • 12V split-rail regulated linear power supply, can be upgraded to 18V if higher voltages are required.
• Theoretical frequency response curves for the 6th-order midrange and woofer tunings available on request, in gnuplot or PostScript format.