DIY Replacing Components in Crossovers

The smart way to go about it, get some high end Deulund bypass caps. Not cheap, but at .01uf you can simply add one to any existing cap and hear improvement without having to buy a cap in some value you might never be able to use anywhere else. Filter caps at .01uf can be used lots of places. The value is too low to affect the circuit, but just enough to smooth and provide rich natural detail.

Next would be resistors. Almost all are the cheap white sand power resistors. Almost anything will be better. Power makes resistors hot, heat increases resistance, resistance lowers voltage. This all happens very fast. Fast enough to affect dynamics. So use quality resistors and don’t hot glue them like everyone does but instead mount them with air flow all around.

Inductors usually have to be measured. This calls for an LCR meter. But you don’t have to measure or even replace inductors to improve them. An inductor is a coil of wire. Coils of wire produce magnetic fields. Magnetic fields interact with wires. To minimize this we place inductors at right angles to each other. At least that is what we’re supposed to do. If your speaker has more than one inductor and they are hot glued flat to the board then you can improve the sound simply by moving one to be at right angles to the other.

Also inductors work slightly better with the signal going from the inside to the outside. Not a huge difference but it is there. If it is easy to reverse the leads then go for it. Don’t cost nothin’.

In case you are keeping score that is 3 crossover upgrades I have given you that cost nothing. And we haven’t even gotten to the rubber bands.

This project you have in mind is one of the most cost-effective and rewarding of all the mods or upgrades you could do. The way you are talking is exactly the way to do it. Don't try and reinvent the wheel. Designing a crossover is very technical and very difficult, especially trying to improve on an already professional design.

Most all of the problems people have are due to changing values. The value of caps and inductors affects crossover points, changes the frequency each driver gets, and messes with the sound. Resistors are like volume controls used to turn the volume down on drivers that would other wise be too loud. Almost all the mistakes you hear about are people messing with these values. So measure and be very careful not to change any values.

Audiophiles love to talk about caps. In reality resistors and inductors are equally important. The better ones don't "change" the sound so much as reveal more of what already is there. As you go better and better (read, more expensive) they remove or distort less and less and so you get more and more of what was already there. This is for caps, resistors, and inductors. 

Here is a good source for many different caps -

Here's one for resistors -

 This isn't really comparative but gives some good info on inductors. Coils make a huge difference!

https://www.erseaudio.com/Products/FoilQCoils

Also if you look at my system page towards the end there are pictures of the crossover upgrade done on my Moab speakers. Several of us on the FB Owner's Group have done projects like this, to varying degrees. Everyone so far extremely happy. You will learn a lot. Good luck!