At that stage, I thought I had enough information to come up with a proper schematic of how and why. the filter should be wired. This wiring diagram uses all the right components, and are properly allocated to the right filter cell. A few calculations confirmed that the woofers were cut off at 400Hz and the tweeter at 6 KHz, which souns quite high, but I personally like to use a higher cut off frequency and also the curves I found for the tweeter were consistent with this design decision.
The midrange is not filtered in the treble as it gently rolls off naturally I suspected, as I could not find any measurements for the SEAS midrange P14RC4, pictured below as well as the mighty FOCAL 8C412 woofer.
I have since found a data sheet - which confirms my guess - here: http://www.seas.no/images/stories/vintage/pdfdataheet/h0522_mp14rcyp.pdf
By the time Perry got a chance to rewire his crossovers to this schematic, he also had received his iTestMic and we moved on to using the FFT measurements:
And I got this lovely email with this FFT photo - I have to say I was quite chuffed...:
"This Jean-Marie is the one that sounds the best by far. It was immediately obvious as so superior to the "correct" tweeter phase which was supposed to be inverted according to the very first schematic from PEL. Of course that schematic was for an old version of the crossover which was not the same as mine.
The white curve is the "inverted" phase while the orange curve is the "correct" phase.
You cannot believe my happiness after so many years of trying and giving up, tearing apart and cobbling back together, sure that this would be the last time. Hours on the internet corresponding to people who didn't know anything. Suggestion after suggestion. Now finally, this is it. How can I thank you enough?
You are a freaking speaker genius.!!! (bold inserted by author...)" Perry G.
Although the saga continued for a while more, let's leave it at that for today!
Born in France, well travelled, relocated to Sydney in 1997.