Old new guy thanks you
Why isnāt it possible? 2 paralleled drivers sum to +6dB sensitivity all the time.
I think he decided against 4ohm+4ohm.
That would be treating two woofers as one dual voicecoil woofer. It doesnāt account for any separation loss. I remember reading DāAppolitoās stuff in Speakerbuilder mag. years ago and I couldnāt figure out how he was coming up with +6 Db. on his MTM. And other readers were also having difficulty too. It finally made sense to me when I thought both electrically and acoustically and that there must be a kind of mutual coupling of the wavefronts at lower mid freq. were the wavelengths overlap considerably and their magnitudes sum. Line arrays do this.
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As far as Iāve been told that is the case. I believe below ~1 wavelength c-c distance is roughly the coupling point. But Iām sure it is more of a gradient than a hard number. Start get comb filtering above there.
I just feel like my simulations should match up better. Iām gonna redo my polars with the woofers separated and try again.
What you have here is a good attempt at a 3.5way. The lower woofer could take advantage of the upper woofer if it was attached after the upper woofer lowpass, and you might not need as large a coil on the lower.
I stink at three ways, but I donāt stink as bad as I did before I found out that I did. I got them all buttoned up and the response looked bad, not like the prototype crossover at all. probably had some inductors too close together. Good thing I can take the bottom off with six screws. I spent a couple days coming up with a new crossover. It has more BSC and more symmetrical slopes. The XO points are approx. 1K and 3K.. I tried to get that mid to go lower but just couldnāt get there. I do like the crispness of the CF-18 tweeter. Itās got me thinking of a small two way using it. The wheels are not motorized, but that would be cool.
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Looking good! Like the wheels. Iām planning to put a pair of casters on my speakers as well.