Attn: Speaker DIY expert

The above answers are all good.

The nicely priced sonic caps are great especially when bypassed with mundorf Caps (silver in oil are good, but the gold ones are amazing if you can afford them). On their own the sonic caps can have a slightly plastic quality although great dynamics and detail. Bypassing with a mundorf 0.1mf or 0.01mf makes for a pin point image with very rich natural texture.

Try the Caddock metal film resistors. I have used the mills, but once burned in the Caddocks are more coherent and have less noise.

Alpha core copper foil inductors are stunning too. The DCR value may be different to what you have, but I doubt dangerously so.

Whatever you need can be found here:(http://www.percyaudio.com/Catalog.pdf) And Michael will also match whatever you order within 1% tolerance. I've dealt with him for years and have yet to be disappointed. Normally I use Vishay Bulk Foil resistors in projects, but actually wire-wounds are known to be quietest. Alpha Cores are the best inductors around, but(as mentioned)a resistance mismatch can cause a shift in your roll off points. The Percy catalog will give you a lot of other ideas also(cabinet damping, binding posts, internal wiring, etc.). Have fun!!

A resistor-tip: to make a good free-flowing resistor you can use lets say 4x32ohm in paralell to gert 8ohm aso. This reduces filter-resistance, the main reason for dynamic loss in passiove filters. Allmost any cheap resistor will do. Components in paralell are the worst dynanic-killers, but this trick lifts the filters power-capasity a lot.

You can do the same with caps in the lower section; only that here the values are added. Like 3x33uF makes a faster 100uf.

For top-caps I`ve used Intertechnic SCR tinfoil. Needs a few months to open up but then they dissapear totally. Not too overpriced ;)

Metallized PolyPropylene(MKP)caps are good. Solen for one and many others are MKP and you pay for their name. You can get cheaper (noname) MKPs at various places. RS might have them.

" For top-caps I`ve used Intertechnic SCR tinfoil. Needs a few months to open up but then they dissapear totally. Not too overpriced ;)"

Sleepy head, here I`m doing a tragic mixup. My long time favorit top-end cap is the Intertechnic KP-SN tinnfoil.Just invisible, perfect and just a little pricy.

But a warning; the worst polypropylene caps I`ve ever heard are called SCR; black w. orange ends. Even if someone give them to you, don't use them.

http://www.elfa.se/elfa-bin/setpage.pl?http://www.elfa.se/elfa-bin/dyndok.pl?dok=2012665.htm

For lower freqences I`ve used the 600V version of Solen MKP. To improve the flow-capasity I run three of them in paralell, like 3x33uf to get 100uf. Combined with thick solid-core wiring this gives a horsekicking free sound.