ETI4000 4 Way Loudspeaker
Electronics Today International Australia Magazine February 1980
Two models were published:
ETI Project 496 Four way 4000/1 speakers February 1980. Crossover PCB ETI496
ETI Project 497 Three way 4000/2 speakers June 1980

Edward J Loudspeaker details
Revision Rev 1.2 2/3/16, Rev 1.3 13/3/16, Rev 1.4 17/3/16, Rev 1.5 18/4/16

PHILLIPS AD 01610/T8 1" DOME TWEETER
- My original model is AD 01610 T8, 2422 257 33602, DD 01 008 111
  20/50W System Power,Resonant Freq:1250Hz, Freq Range:2-22 KHz
  96mm Overall Diameter, 85mm Baffle Hole Diameter, 32mm Total Depth, Textile
  Square Semi Exposed
- 3kHz Crossover in ETI4000 speaker system
- AD 01600 W8 is exactly same specs but exposed
- AD 01605 W8 is exactly same specs but with aluminium trim rings
- Bought substitute AD 11600 T8. Can not find the specs but it is supposedly
  the square version of AD 0163/T8 the specs for which are
  20/50W System Power,Resonant Freq:1300Hz, Freq Range:2-22 KHz
  94mm Overall Diameter, 75mm Baffle Hole Diameter, 32mm Total Depth, Textile
  Square Semi Exposed

Mid range 2" Dome Squawker AD 02161/SQ8
- My original model is 2" Dome Squawker AD 02160/SQ8, 2422 257 32312, DD 03 016 101
  80W System Power, Resonant Freq:320 Hz, Freq Range:0.5-10 KHz
  134mm Overall Diameter, 122mm Baffle Hole Diameter, 85mm Total Depth
  Back of speaker is enclosed
- 750Hz-3kHz Crossover in ETI4000 speaker system
- Bought substitute AD 02110/SQ8
  80W System Power, Resonant Freq:340Hz, Freq Range:0.5-5KHz
  134mm Overall Diameter, 112mm Baffle Hole Diameter, 103mm Total Depth

Mid woofer 7" AD 70601/W8 or AD 01605/W8
- My original model is 7" AD 70601/W8, 2422 257 47102, DD 00 918 94
  30W System Power, Resonant Freq:45Hz, Freq Range:0.04-3KHz
  166mm Overall Diameter, 142mm Baffle Hole Diameter, 68mm Total Depth,
  Rubber surround
- 150Hz-750Hz Crossover in ETI4000 speaker system
- AD 70610/W8 and AD70611/W8 have cloth surround instead of rubber and
  slightly different frequency response.
  AD 70601/W8 40Hz-3KHz, AD 70610/W8 and AD 70611/W8 50Hz-4KHz  
- Bought substitute AD 70611/W8

Woofer 12" AD 12250/W8
- My original model is AD 12250/W8
  100W System Power, Resonant Freq:26Hz, Freq Range:0.04-2KHz
  311mm Overall Diameter, 280mm Baffle Hole Diameter, 121mm Total Depth,
  Rubber surround
- 150Hz Crossover in ETI4000 speaker system
- AD 12552/W8 12" 100W woofer is later model. Foam surround instead of
  original rubber
- Bought substitute AD 12200/W8 which is 80w version of AD 12250/W8 100W.
  Frequency range is also slightly different. AD 12200/W8 details:
  80W System Power, Resonant Freq:23Hz, Freq Range:0.04-2KHz
  311mm Overall Diameter, 280mm Baffle Hole Diameter, 121mm Total Depth,
  Rubber surround