Mtg designs

[Drummer]

Matt has his diy design site up and running. He has been one of diysoundgroup 's main designers for years. Hopefully, you may find this of interest. Glenn.
https://www.mtg-designs.com/diy-speaker-plans

[Wolf]

Well, I can tell you this- there is no such thing as an LR3 xover.
Wolf

[Drummer]

Well, I can tell you this- there is no such thing as an LR3 xover.
Wolf

Would it only be a Butterworth, or Bessel, based on slope/peak/dip/summation? This may be an idiot question, but I am trying to get a grasp on technical matters beyond my understanding. I know that you have different design approaches than another might , and I am blown away with your knowledge, and expertise. I tend to pick up enough to confuse myself! 😁Glenn.

[a4eaudio]

Those crossover PCBs on his site are sweet.

[billfitzmaurice]

Would it only be a Butterworth, or Bessel

Those are the most commonly used alignments, but you don't have to use a filter that has a specific Le/C value ratio. It's like loudspeaker alignments (QB3, BB4, C4, EBS, etc.) Alignments were useful in the days of manual calculations, but with modeling software you can tweak any and all box parameters to easily arrive at a desired custom result. The same applies with crossovers. Software like XSim allows you to make far smaller adjustments to the component values than using an alignment, again for a desired custom result. We actually did that in the old days, starting with an alignment, then substituting component values until you were satisfied. To that end it was common to put the crossover on the outside of the cabinet back to easily swap components.

[Wolf]

Bill explained the gist of it, but as far as textbook alignments go, LR is all-pass and even-order only, with a general Q of 0.5 in terms of how the transfer function corrects the knee to sum flat. More often than not, you can have a 3rd order electrical on the tweeter, and a damped 2nd order on the midbass, and come out at an LR4 applied transfer function acoustically. There are builders or designers that do not make the connection between electrical order and acoustic result, and often mis-state the measured/simulated result as something other than what it is. I will say I was in this boat at one point as well. I just stated the targeted acoustic slopes as my result, but neglected to look at the system as a whole. For instance- if you have a deep reverse null then the system is aligned in phase, and actually an even-order acoustic result, even if the slopes are 3rd order and 5th order aligned to targets. Odd order acoustic alignments do not have deep reverse nulls.

I'm not as knowledgeable as some others that post here and elsewhere, don't get me wrong, but I really try to be accurate in my statements. Just like JeffB; John Kreskovsky, feyz, DLR, DDF, jcandy, and others are definitely more wise on the subject than I am. I have just learned a lot from them, through my own studies, and by experience in builds. Let's call it what it is, 20 years of doing something should really have something to show for it if the person climbs the rungs of the hobby's ladder.

Later,
Wolf

[Drummer]

Thank you, Bill, and Ben. I will continue to try and digest the information, and hopefully, I will get more pieces of it to stick to my brain. 😁 Glenn.