Hi there,
Wondering if anyone has the ETI magazine article for these speakers?
I think they were ETI 4000 or ETI 4001. Each speaker box has 4 speakers,
12" bass, 7" low-mid, 2" dome hi-mid and 1" dome tweeter. Box stands a metre high and the Rod Irving ones are 19mm chipboard.I built them way back around 1980 or so, from kits by Rod Irving Electronics in Thornbury, the passive crossovers were by Selectronics (? I think) Very expensive at the time and improved a great deal a few years ago when I replaced the bipolar caps in the thing. Bass was always a bit low response but nicely defined since they're sealed enclosures.
An extra sealed inner enclosure for the 7" low-mid speaker.
I'm interested in seeing the original design specs, like crossover frequencies. Reverse working from the circuit is a bit difficult.
I'm considering ripping the passive crossover out, at least for the bass, maybe go three-way active? Dunno, all fluffy ideas at the moment. Was quite amazed how new higher voltage rated bipolar caps helped the bass along, been thinking quite some time about going to active crossovers, get rid of the E core laminated low frequency inductors and bipolar caps. I imagine the hi-mid and tweeter are okay with passive xover, or I could drop something active up there too, not so much power required?
Ideas welcome :)
So, does anyone have a copy of the articles they could scan? Last time I checked there were no library copies available, even our local uni had dumped their magazines from that era. Or is there an online magazine repository?
Thanks, Grant.