free xover service

[Ianm2]

if anyone has drive units and wishes a proper xover doing, I will be glad to do it for nothing.

It will be at least 95% to commercial standards, 2 way, 3 way, 4 way!!, perfect phase or otherwise

Provided I have drive unit data viz spl and impedance plots.

It doesn't use the mostly useless formulae on the interweb or books, and is the real deal.

Get you started and you may wish then to commission Peter, should you be unhappy.

If I can get my parallel port up and running i will be able to mail you the schematic and plots, just for postage, otherwise, a paint version.

[petercom]

Look, I don't want to keep on harping on about this but you can't do this from drive unit spl and impedance plots. How do you take into account:

Baffle step
Cabinet and drive unit reflections and interference
Drive unit spacing
Enclosure performance (both internal and external)
Phase and time arrival

These are all unknowns until you actually measure the drive units in the cabinet you are going to use. You can then export the spl and impedance plots and put them into LspCAD to play around with a 'virtual' crossover.

Anything else is a waste of time. You might as well just start off with a first order crossover and refine it, add sections, and so on just by listening. You'll get there just as quickly.

If you want more info have a look at my Speaker Design articles in HFW. The last two articles show exactly what goes wrong when you make assumptions based on manufacturer's data!

[Ianm2]

appreciate that, I have actually done all the previous world audio ones I have in the articles, about 7, and they are coming out identical, so that does raise questions about how they were designed if that's the case. I am aware of those extra issues, but according to the xovers in the kls articles, these are indeed working out without taking all those factors into account.

I will be implementing my theoretical one, to try, so may be buying a few components off you soon, and see the results.

the point of it,tho, is a get you started for people who just use the forumlae which are totally useless, this does yield 95% correct results, and some of those factors are actually predicted.

its not lspcad tho'.

best wishes!

[petercom]

Sorry if I came across a bit hard on your offer - didn't mean to, but it just riles me when I hear from so many DIY speaker builders who have been given 'theoretical' crossovers and can't get their speakers to sound good.

If you really want to check your system I can send you some drive unit data and then plug your results into the 'real' speaker design and show you what the actual results look like.

[Greg.]

Hi Ian,

On KLS speakers, it's worth noting that the crossovers published in the DIY supplement articles were not necessarily the final spec and represented initial design which was later tweaked before the kits went out. That is exactly the case with KLS3 and I believe other kits.

Brest wishes,

Greg

[Ianm2]

Hi Peter, yes that would be most useful, its a very interesting, kind and generous offer, I would love to have a play.

its a very good program indeed, much better than anything out there bar the real pro stuff, like linearx, and probably a lot more easy to use as well.

you can email me or pm if you want details of how to contact me for that. I will do the same.

its certainly not indended to be competition for yourself, more for people who can't afford the full service to get them more there than they can get with the junk around the web and books.