I did the math, and first I tried to derive some equations to calculate the component values directly, but I haven't messed with differential equations since last year... so that ended up as page full of chicken scratch.

so I decided just to loop a million times and make little adjustments, works like a charm.

If anybody wants to try it out. here's the link.

of course, you have to have the visual Basic Runtime dll's...

• http://dsb.8m.com/pipics/lpad.htm

Are you up to adding functionality for an optional bypass capacitor across the series resistance? It would also be great to allow for driver Re and Le and to plot a response curve for each of these circuits too; Spice is sometimes difficult to use and your app is much more attractive and easier to use.

I can imagine an incredibly useful applet forming on your computer...

sure, I'll add some more stuff to it.

The response curve idea is cool. the rough model using Re and Le should give a pretty good picture of what it looks like.

if there are any more suggestions or questions (I'm no the best at designing easy to use stuff) from anybody that would be cool.

Thanks,
Danny

It works, and looks really good.

but, since I'm not accounting for driver resonance in a horn or whatever (just Re and Le), the graphs don't look exactly like the ones from Spice.

I'll finish it ans upload it in 30 minutes or so.