Building Passive Crossovers

[shizzzon 461]

I've been doin some research about this so if i make a mistake, let me know.

I got a chart from the12volt that lets me know what inductors and capacitors to use for a desired slope and roll off and diagrams for slope configurations.

I also know what VDC one should shoot for based upon power used.

Now, i would like to start studying the parts themselves.

I'm starting with capacitors first.

From what i'm reading, for high quality, low distortion use, to use caps that start with poly-... preferably polystyrene film caps.

I would like to purchase all my parts from partsexpress.com and these are the ones they offer-

Audiocap Theta Polypropylene Film

Auricap Metallized Film

Dayton Metallized Polypropylene

Dayton Film and Foil Polypropylene

Jantzen's Crosscap

Which should i use for the lowest distortion possible. If there are any other features i need to look at besides low distortion, let me know! I already know about tolerance % ratings.

Also, I read this from Richard Clark-

He says regardless of what cap to use, he suggests using a bypass cap specifically made of polystyrene cap @ 0.01mf soldered with the tweeter crossover cap to lower distortion at it's greatest.

Now, i have many questions about this....

Do you guys think it's a good idea when using one of the 5 caps above?

When building a 12 or 18db slope, should i install a bypass cap to both tweet caps or just the first one?

Clark also states to install a safety cap in place to protect the tweeter....

safety cap is calculated by halfing the crossover frequency of a 6db configuration and using that figure as the safety cap..

Now, how am i to build a 12 or 18db slope using a safety cap? He never really explained that.

I think that's it for cap talk i can think of right now. After i get all this info down, i'll be lookin into inductors next.

[///M5 2,833]

You need to worry WAY more about the layout and design and WAY less about the components. The cause of an issue in your sound will be unrelated to any of the above.

Until you really know what you are doing the Dayton caps are more than adequate for your needs.

Instead of creating a series of non-sense threads, please instead consider making a thread discussing what you are trying to accomplish and specific questions towards that. This won't go anywhere good.

[Tirefryr 1,742]

He He He.

[shizzzon 461]

ok, basically i need loud and i want to be able to get the full use out of my 100.4 sundown bridged for doing it.

I decided to go the Pro Audio route and find me some 6.5s that are capable of handling the 300wrms i want to throw at them.

the lowest recommended response i've found for some high powered 6.5s go down to 110hz which is fine for me.

This setup is for a certain division in spl competition where the music must be able to be heard while the bass is being mesured.

I decided to use a single pair of 6.5s in the doors and 1" soft dome tweets. I haven't looked for tweets yet because i wanted to venture over to the crossover section and get some info first.

So u can see i'm not lookin for harmony but when reading about how some caps can easily cause distortion, i'm not familiar with what i am being told so if this distortion is audible from using bad qualiy caps then that's a no-go because this front stage is also used for light musical playback as well. Light meaning low to moderate volume levels.

My current setup is a set of ID 6.5s CTX65CS - CTX65CS - Image Dynamics 6.5" Component Speaker System

While i do like the sound of this component set, i needed it to be louder as well and it just wasn't gonna happen.

I like to know how to build these in general regardless as something else to do if i ever have\want to.

[///M5 2,833]

You will never find a tweeter that will take 300w and are going to have to pad the shit out of it to match a single 6.5 driver.

Considering your goals you can use the cheapest capacitors you can find and you won't hear the difference, in particular if the amount of design time you are going to put in is based on the calculator thingee you found. Same with inductors and whatever else. Easy to put this way, you can't even buy anything as cheap as the junk that come in component sets.

Define "music heard" as this is foreign to me. How can they tell you they can't hear it? ie what level below the bass is acceptable and what level of bass are you trying to achieve. Stupid parameters for a competition btw.

[Impious 1,476]

If you are just look for cheap and "loud" without much concern to actual performance I'd say skip building them and just buy the predesigned passives from partsexpress with a xover frequency that isn't going to fry your tweeters. You probably wouldn't be able to build a pair cheaper.

[shizzzon 461]

well i am gonna use a 4 ohm woofer and 8 ohm tweeter. i will run them active first so i can establish my xover points then go from there. if there is one that fits my needs then yes, i will buy one. if i havve to build one, i am still tryin to figue out how i am going to enclose it inside of something... you got any suggestions for that?

[///M5 2,833]

Put them in a box. Why not just add a cheap little amplifier for your tweeters and keep it active. It will sound better, will be cheaper, and way more flexible.

[shizzzon 461]

Off my cell phone now, reading will be more legible, lol.

While you are correct, that is the perfect way, and i can do this later on down the road, right now i cant.

Besides, i'd rather do something i've never done before and just know how to do it. Just somethin for fun.

After i tear my wall down later on this year.. then i can run all the active i want.

[///M5 2,833]

While you are correct, that is the perfect way, and i can do this later on down the road, right now i cant.

I am curious why you "can't" add an amp right now as from your posts I can tell that you can't build a passive either.

[shizzzon 461]

I have a wall...

I can't run anymore wire from front to rear until i tear it down.

I only have a single run of speaker wire on each side of the car.

[///M5 2,833]

Is your front stage in the wall?

[shizzzon 461]

no it's in the doors. The wire that feeds in is ran along the sides of the wall completely covered in expanding foam.

Once i tear the wall down, everything, and i mean everythign is coming out, even the headliner. The car will be rebuilt and reinforced for a new box design.

[///M5 2,833]

Put a small amp up in your dash, under your seat, in your center console, or whatever. You don't need much for the tweeters to get loud.

Building a passive isn't a good solution for what you want to do.

[alexj01_83 6]

You will never find a tweeter that will take 300w and are going to have to pad the shit out of it to match a single 6.5 driver.

what about these

Would they be close i have a set in my car and they take a pounding.

[///M5 2,833]

Lol, nope. And why would anyone ever want anything called "the screamer". That cracks me up.

[Impious 1,476]

You will never find a tweeter that will take 300w and are going to have to pad the shit out of it to match a single 6.5 driver.

what about these

Would they be close i have a set in my car and they take a pounding.

You will never find a tweeter that will handle an actual 300w.

[Mac N Cheese 90]

Lol, nope. And why would anyone ever want anything called "the screamer". That cracks me up.

x2

[alexj01_83 6]

Lol, nope. And why would anyone ever want anything called "the screamer". That cracks me up.

x2

So aside from them being nick named "The screamer", are they crap??? I have never had a problem with em.

[Impious 1,476]

If you use them and like them, why are you asking us if they're crap?

[jcarter1885 995]

If you use them and like them, why are you asking us if they're crap?

x2, everybody has a preference. There will be people on here who wont agree with everyone's equipment selection but if you like it then enjoy it but is there better out there more than likely.

[///M5 2,833]

Lol, nope. And why would anyone ever want anything called "the screamer". That cracks me up.

x2

So aside from them being nick named "The screamer", are they crap??? I have never had a problem with em.

I've never heard them, never will, and either way it doesn't matter if YOU like them.

[95Honda 486]

The safety caps have nothing to do with a passive crossover. These are reccomended for active systems, when you aren't sure how well your gear works....

[shizzzon 461]

the tweeters i was looking at are made by Morel.

They are rated for 200wrms 8ohms and can be HP'ed as low as 1.6khz.

That's plenty capability as the amp i have probably can only do, if that, 200w@8ohms.

[///M5 2,833]

200w at 1.6k will kill those REALLY fast. In particular if you build a 1st order network.