crossover 101 on building some modified 3133

[Wardsweb]

I have a few basic questions. I plan on getting most parts from Parts Express.

Any recommended source for the higher wattage resistors or just use several to achieve the current and resistance ratings?

Can I use all air core inductors or should I go with iron core for the woofer?

Does wire gauge make a big difference on the air core inductors?

Should I spring for the AuriCaps or will the Dayton audio be ok? Maybe Auricaps on just he tweeters?

Any recommendations, suggestion, tips or tricks, if you were building these?

BTW: LE15A woofers

[Ruediger]

The 3.3 mH coil should have the same DC resistance as the original, I think You need a core here. The other coils should not be critical.

There are tricky arrangements of coils, such that they do not couple with each other. Do a search in the internet for that.

[DavidF]

You can use multiples of 10 watt parallel resistors to spread the load. In other words 4 16ohm in parallel will replace one 4 ohm. Not perfect in that each of the four will not share an exact current load due to variances in resistance. The original design assumed an application with high volume and high current potential. If you are certain that your intended use will not approach this potential you can do with less in terms of the two 40watt spec'd resistors. If not sure then note that Parts Express also stocks some 20 watt components. Two parallel 20 ohm will get you to 10 ohms, two 8 ohm to get you to 4 ohms.

The matter of which caps to use opens up the proverbial door to cost/benefit and which sound better. I will say I have used Daytons polypropylene often and especially like their 1% tolerance units. Probably the same as their standard poly with the price difference due to the tighter tolerance. Irks me to spend far more on "better" caps that have something like a 10% tolerance. I have to measure and tweak the values with bypass which is more $$. Otherwise I use Clarity Caps a lot (SA or ESA, check Madisound).