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Hi, I mean this in a totally polite way, but I think you're attempting something which is not likely to have a good end result. 1michael is on the dot about just how many things have already gone wrong with your build.

my advice is to start with measurements measurements measurements.

You need to measure driver impedance, driver sensitivity, driver on-axis freqency response, driver off-axis frequency response, phase response - all in the baffle and preferably outdoors. You can't use any old crossover - it's like trying to build a toyota camry with random parts and a 1960s engine design schematic. Here is a page you really need to read:

http://www.troelsgravesen.dk/crossovers.htm

And read it over twice.

If it's not too late, your best bet would be to start with drivers that will work well together both on AND off axis. The Dayton RS52 is a good dome midrange which might have good off axis response and stored energy to work with. If going passive3 way without much knowledge of speaker design, an existing design is VERY MUCH the way you almost NEED to go if you want things to sound coherent and lifelike. The Zaph ZDT3.5 might be a place to start.

Going active is a very worthwhile venture as well, especially for the unexperienced. I wish you luck, but you may need a miracle. :T
 

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If you have limited funds, designing your own speaker is probably going to be out of the question, because at the very least you would need to purchase a measurement microphone, mic preamp.

Luckily since it's an active crossover, you can probably skip getting a woofer tester, and maybe it can be salvaged. Active is a good bit easier to work with than passive, at least.

Where abouts are you located? Perhaps you can meet up with someone to help measure your gear for you.

What you need to start with is a baffle. The ATC unit you're looking to recreate is likely not the ideal design for a baffle layout for starters. You also want to round edges, offset small drivers,

Next, in that baffle, you need to measure each individual driver. You need to measure not only frequency response and off axis frequency response, but also determine where any cone breakups might be so they can be placed well out of the driver passband and notched accordingly.

Your goal is hopefully to be able to get crossover frequencies where the off axis response as far out as 60 degrees is matching between the individual drivers (directivity index matching) and remember that using a 2nd order electrical filter may in fact implement a total 3rd or 4th order acoustic rolloff on a driver... that's where on axis frequency response comes into play.

Also remember that crossing over too low or too high for a given driver will introduce distortion. You may in fact find that some of your drivers simply can NOT work with each other effectively.

You may also need to apply equalization to on-axis frequency response to smooth it out via the crossover. I don't know how functional your Rane unit is in this regard. A parametric EQ can also be used ahead of the signal. Don't bother trying to equalize below the shroeder frequency in-room, and don't overzealously equalize either. Hopefully you can get +/- 2db on axis tolerance from around 200hz to 8khz or so, and a smooth off axis rolloff as you get higher in frequency.

Phase is also a factor you need to consider... Just try to match phase between drivers at the crossover frequencies. Sometimes inverting the leads is all you need to do.
 

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Where would you recommend measuring at and from. (location and distance) and should I just push pink noise? or do you have something else you would test with?


Location - outdoors
Distance - 1m or 2m or both.
Test tones - most measurement programs have built in test tones.
Could you explain what you mean by cone breakup?
Trying to a play a large cone too high in frequency will cause its diaphram to "break up" and produce distortion. This can affect time domain and frequency domain response and must be dealt with appropriately.
 
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