Attn: Speaker DIY expert


I want to upgrade the crossover on my DIY monitor. It's a Jim Griffin design with Jordan JX92s and Aurum Cantus drivers. I put some no name brand crossover parts from Radioshack on it . Can somebody tell me what is the best capacitor, resistor and coil to buy. Please include the type and brand and the store where I can buy them.

Here is the list of parts that I need:

L1 = 1.5 mH 16 awg.
L2 = 0.3 mH 20 awg.
C1 = 6.8 uf
C2 = 5.1 uf
C3 = 15 uf
R1 = 8 ohms 10W
R2 = 3 ohms 10W
R3 = 1 ohm 10W
PCB board.

Thanks everyone, I appreciate taking your time.
royy
Elctroid is right on. I would not replace the inductors, unless you can account for DCR change, and can measure both old and new inductors yourself. If the Rat Shack inductoirs are really bad, I suppose if you stick to the same wire gauge and just upgrade the inductor to solen you would be OK.Maybe you could ask the original designer.

I would avoid foil inductors also as they are a bear to solder, unless you know how to do this. I think Sonicap will make the cap values you need, and Mills are 1 percent tolerance. Make sure you have enough room for the new parts.

Ceramic wirewound resistors (non-inductive type) and polypropelene caps (double layer film) and air core inductors (mounted with brass of course) - appropriately rated - these get my vote. Practical and relatively inexpensive (generally a few dollars each).
" 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.
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.
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 ;)
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!!
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.
madisound.com would be your friend. I agree, stick with caps and resistors. You can start with something like solen for a few bucks per cap and go al the way up to Mundorf silver or gold and spend a couple hunderd per cap.
Look up Solen electronics for parts
Also look at Parts Express for ready made xovers
Watch out with inductor replacement. They will likely have a different DCR which can have a negative affect. Stick to caps and resistors. A good mid budget upgrade might use Mills resistors and Sonicaps. It's always a little tough to find exact cap values. Crossovers aren't that complex and don't require a PC board. You can point to point wire them on a piece of nice wood. Glue or wire tie the caps down with a deflex pad under them. Good luck.

ET