What crossover components do you keep on hand

[nunayafb]

So Im getting close to the point where Im going to need some caps and inductors and a few resistors laying around for xover prototyping. I am curious about those of you who have built a few, do you keep a stock of many values or do you model the xover on computer and order just the stuff that you need.
I have no problem bying a bunch of different values but obviously they cant be the high end types, so does anyone here prototype with low grade and then swap in good stuff when finalized? Does quality only affect tonality and the "subjective" stuff, or is the measurable FR and distortion etc.. also affected.

Also does anyone here use variable caps/inductors for prototyping or voicing? Having virtually no experience with truly designing xovers Im trying to approach this with the right tools and methods to minimize time/money wasted

I keep hearing that no matter how well you model it you still need to tweak it (voicing)to get it right. This seems like it would require a wide range of component values to make small changes, of course Im guessing at this.

I still have to re/search for what brands or types of each components are acceptable or need to be avoided, if you are so inclined feel free to provide info on this. It will save me time

Thanks,

 

[lndm]

I like to get handfuls of components when they are conveniently and/or cheaply available. If I can get a handful of components of the same value, I know I can make any value from them if necessary.

I like to have a handful of sand cast or carbon power resistors, a handful of mylar caps, a handful of bipolar electrolytics and a range of 14ga inductors.

Often after a tweaking period, replacing the components with decent single values etc. and soldering, can make a welcome difference. It is sometimes a big enough difference to warrant further tweaking, but usually I am happy enough (till next time I feel like tweaking )

I typically replace my mylars with polypropylene caps, my bipolars with motor run caps and the sand cast resistors with carbon (just my preference).

The inductors will probably give the largets issues due to their DCR. Since quality inductors tend to be expensive, I usually make do with the 14ga ones for tweaking. Of course, if used in series with a resistor, the small air cored inductors will be just what you want anyway.

 

[ocool_15]

I usually model with software to get an idea of what ill need, buy those parts and a few extra of similar values. For a mid/tweet crossover I have been using 20ga-18ga inductors. For lower frequencies parts become much more expensive. Inductors in series with a speaker have an Re so therefore will reduce there sensitivity

 

[Cal Weldon]

I like to buy a cap and coil, one value either side of the one I'm starting with and then after a few years of doing this you have drawers and bags full of the stuff

 

[nunayafb]

For lower frequencies parts become much more expensive. Inductors in series with a speaker have an Re so therefore will reduce there sensitivity

So would hand winding large gauge inductors be beneficial, if so what wire gauge does everyone recommend. Is standard magnet wire used or is there something with lower dcr?

 

[ocool_15]

So would hand winding large gauge inductors be beneficial, if so what wire gauge does everyone recommend. Is standard magnet wire used or is there something with lower dcr?

I seen a ratio given in Loudspeaker Design cookbook, I believe it was 0.4ohm for 8 ohms and 0.2ohm for 4 ohms but I'm not certain.
Magnet wire is whats used. The gauge of wire will depend on you.
Lower gauges
Handle more power
Increase cost
Lower dcr
Require More wire for a given value.

Cored(ferite ect) Inductors are usually cheaper and have a lower dcr but sonically are generally accepted as inferior.

A wonderful site Air Core Calc

 

[ocool_15]

Define a large value like 10mH or 2mH or?

 

[cominup]

In crossover circuit, we got notice: "500 turn x 1/4". any one knows "1/4" is 1/4 inches or another meaning?

Do you know how many turns to get an inductor 1.2mH and 4.5mH in air core?

Thanks.

 

[ocool_15]

In crossover circuit, we got notice: "500 turn x 1/4". any one knows "1/4" is 1/4 inches or another meaning?

Do you know how many turns to get an inductor 1.2mH and 4.5mH in air core?

Thanks.

1/4" I am unsure what that is referring to, is it a cored bar inductor? Try my link for air core calculations.

 

[nunayafb]

thanks for the link, more good links on that one.