Thinking about crossover design

[Feanor]

I haven't given much thought to the subject for a year or so, but I'd like to get started again. I'd like an find easy to use software that will model any, user-defined topology.

Right now I have Harris Tech's X-over Pro which meets the first criteria very well however it has significant deficiencies:

Won't handle any topology, that is, you work with predefined 'orders' and their corresponding standard component configurations;
Won't incorporate notch filters of baffle step compensation;
Doesn't model empirical driver phase measurements or physical driver placement;
Doesn't seek optimum component values for a flat response by iteration or other goal-seeking methods, i.e. it exclusively formula driven, (though you can manually change component values and it will re-compute the response curve).I would prefer that the new software work with:

Thiel-Small parameters only, but also
Empirical FR, impedance, and/or phase measurements which can be entered manually.I have an old version of the CALSOD program which will pretty much do these things but it is a very user-hostile, DOS program and I'm not even sure it will work on XP/Vista.

[kexodusc]

The best one I can think of is Soundeasy.
I'd recommend a newer CALSOD, but aside from the price scaring you, I don't know who sells it anymore.

Most software does MOST of what you want, but not all. I'm not even sure CALSOD does it all. None are terribly user friendly

I think a lot of people are using the FRD Consortium free toolsI like Passive Crossover Design...it's doesn't have an optimizer, but you can manipulate the transfer functions yourself to accomplish the goal. I've had great success with this to get in the ballpark, and then measured to figure out what components to tweak. Not as fast, and relies on other free software to to model baffle response unless you have measurement setup and can create frd. and zma files. Speaker Workshop is great for this.

[Feanor]

The best one I can think of is Soundeasy.
I'd recommend a newer CALSOD, but aside from the price scaring you, I don't know who sells it anymore.

Most software does MOST of what you want, but not all. I'm not even sure CALSOD does it all. None are terribly user friendly

I think a lot of people are using the FRD Consortium free toolsI like Passive Crossover Design...it's doesn't have an optimizer, but you can manipulate the transfer functions yourself to accomplish the goal. I've had great success with this to get in the ballpark, and then measured to figure out what components to tweak. Not as fast, and relies on other free software to to model baffle response unless you have measurement setup and can create frd. and zma files. Speaker Workshop is great for this.

Thank, Kex,

I start by checking out the FRD options -- I like the price. I think Soundeasy is pricey (?).

Measurement isn't going to work for me because (1) I'd rather avoid buying the equipment, (though there are some reasonably priced options, I think), but more particularly, (2) I want to model before I buy the actual driver.

[Dusty Chalk]

I say screw it, buy a cheap computer, and use that as your crossover.

[kexodusc]

I say screw it, buy a cheap computer, and use that as your crossover.

I'm all for digital crossovers. Only problem being in simpler designs, you can usually afford far better quality components which do affect sound quality significantly, and still save a ton of money. And personally, I usually like the fact I don't need another piece of electronics for the speakers to work.

Up to you Feanor.

[hermanv]

The industry standard program is Leap. They make a enclosure designer and a crossover designer. It is not cheap. http://www.linearx.com/products/software/LEAP5/LEAP5_01.htm

My friend and I used it to design our 3 way. It generates a mathmatical model of level and phase of each driver mounted in a baffle or enclosure and then imports that data into the crossover shop. It will pick values for you or you enter your arbitrary design and it calculates the resultant response.

Next it has an optimizer, You input a desired response curve, tell the program which of the component values it's allowed to adjust and it calculates the values that will most closely match the curve. You can add lumps, bobbles or valleys and it will still match that curve as best as it can, traps are no problem.

It does SPL, Impedance, Phase and predicts lobing. You can model the listening position and I believe you can model the room.

If I remember correctly for our 3 way design, the predicted response from Leap matched the measured response from MLSSA within a dB or so.

[kexodusc]

Oh, can't believe I didn't think of LSPCad...this is the program we use at our local DIY club at the University. LSPCad claims to be the number one design program world wide. I think it's also the most expensive and you'll definitely want a measurement setup, but it models pretty much everything. It's the big name in Europe, though I think LEAP is cheaper on this side of the pond and probably a bit more popular in North America too. I'd love to have either, but unfortunately I just can't justify that much cash for the hobby thing yet.

[hermanv]

I think Leap costs as much as a pair of good speaker cables. It isn't really for the faint of heart. While the interface is windows graphical like, speaker design is complex enough that a truly simple program just can't do the job.

So it kind of depends on your depth of involvement. We just couldn't afford truly first class speakers (I think of those as running $15,000 a a pair and up) so we spent half that to make 2 pairs. We also invested 8 years calendar which is probably about a man year of real time in the project.

If you want to make one two way center channel, this isn't the program for you.