External crossovers

Christ, they definitely can get expensive!

The capacitors are only a few bucks each, but the inductors can get way up there in price!

Check out www.madisound.com, I have used them for all my passive crossover builds in the past, and they have great products and service.

The bottom line is, the steeper you make the crossover slope, the more expensive it gets, because each time you steepen the crossover slope by 6dB/octave more, you add on another capacitor and another inductor.

 

seems to me civic that you dont know much about car audio for a

moderator. wanna hand the position down to me?

lol. im just kidding..........


jeff

 

That is pretty much all you are capable of moderating. Lord knows you can't accept any other type of moderation because of your lack of knowledge.

 

PS are you just naturally a Dick or it is just a keyboard thing?

 

Why do you post those news bits on CAF?

Like the Kmart Logo, and all the current events on CAF? Why don't you post them here, at YOUR forum?


I will continue to do my best at flaming this board in general.

 

Why do you post those news bits on CAF?

Like the Kmart Logo, and all the current events on CAF? Why don't you post them here, at YOUR forum?


I will continue to do my best at flaming this board in general.[/b][/quote]
you know I can stop that at any time

and FYI bud I have a NEWS section smart guy


your going to get me on a bad day and I am going to eliminte your problems


I dont know why you dispise this board, and frankly I dont care

if you dont like it, leave , you will not be missed I assure you

from the time I have been posting on CAF and here I very soldomly see you post anything useful it is all sarcaism, or flaming, yet you bitch when people flame you :unsure:

Again, if you have a problem with this board or me, LEAVE, I am sure none of my members will miss you, and I know I will not

Have a nice day

 

you know I can stop that at any time

and FYI bud I have a NEWS section smart guy


your going to get me on a bad day and I am going to eliminte your problems


I dont know why you dispise this board, and frankly I dont care

if you dont like it, leave , you will not be missed I assure you

from the time I have been posting on CAF and here I very soldomly see you post anything useful it is all sarcaism, or flaming, yet you bitch when people flame you :unsure:

Again, if you have a problem with this board or me, LEAVE, I am sure none of my members will miss you, and I know I will not

Have a nice day[/b][/quote]
I want you to stop posting from now on.

If you think all I post at CAF is pish posh, do a search. Clearly you are mistaken my young friend.

I will try my best to flame as many people on this board as I can.

Thanks, have a good day.

 

I want you to stop posting from now on.

If you think all I post at CAF is pish posh, do a search. Clearly you are mistaken my young friend.

I will try my best to flame as many people on this board as I can.

Thanks, have a good day.[/b][/quote]
What is wrong with you? Is something wrong in your life and you decide to vent on the internet forums?

 

Crossovers, the steeper the slope the better.
What does the slope mean?
What do the terms mean?

A low pass crossover allows the lows to pass... ie. it blocks the high frequencies.
Vice versa for a high pass crossover.

Let's look at a low-pass crossover.
Say, a subwoofer crossover, set to 80Hz.

And first, realize that because the frequency scale is a logarythmic one, every time that you double the frequency, you traverse exactly one musical octave.
ie. 20-40Hz is one octave... 40-80Hz is another one... 10,000-20,000Hz is another one.

Example:
An 80Hz low pass crossover... pretend you are playing through it at 120dB:
If it had a cutoff rate of 12dB/octave, that would mean that at 160Hz, it would still be 108dB... (that's one octave higher than 80Hz)
At 320Hz it would still be 96dB loud... (one octave again..)
At 640Hz it would still be 84dB loud... etc.. etc... etc..

Now, compare that to if that same crossover were 24dB/octave:
160Hz would be 96dB loud...
320Hz would be 72dB loud...
640Hz would be 48dB loud... etc.. etc. etc..

Better, Civic?

 

Think about what a low-pass crossover is supposed to do...
Allow all the bass to get to your subwoofer, and block off the higher frequencies so that they DON'T get to the subwoofer, right?

so, ideally it would be a wall, just a pure cutoff..
An 80Hz low pass crossover would allow anything below 80Hz to get to the sub, and nothing over it.
But that's impossible...

In reality, it is just attenuated at some rate above 80hz (or whatever frequency you set it at, you know), so that at least, if they aren't totally cut off above 80Hz, they are at least attenuated.

And like i said, every time you double your frequency (ie. 80 to 160Hz, 160 to 320Hz, 320 to 640Hz, 640 to 1280Hz etc..), you are going up one octave.
This is important, because the attenuation of a crossover is defined in terms of the slope that it can attenuate at...
6dB/octave, 12dB/octave, 18dB/octave, 24dB/octave, etc..

The steeper the slope, the closer to that perfect "cutoff" that would be ideal.

The example I quoted above is simply a comparison of what the levels of sound would be that the subwoofer would be producing (or rather, the level of the signal that was able to get to the subwoofer! ), comparing a 12dB/octave Xover (the first one) to a 24dB/octave Xover (the second one).

This is also relevant as far as your question was concerned, as to the expense involved in building your own passive crossovers, and my point as to their expense...

a 6dB/octave low-pass crossover is just a single coil (and a 6dB/octave high pass is a single capacitor)...
a 12dB/octave low pass crossover is a single coil AND a single capacitor, with the capacitor wired in parallel...
an 18dB/octave low pass crossover requires two coils, with the single capacitor wired in parallel...
a 24dB/octave low pass crossover requires two coils and two capacitors...
And that's just for one channel!
Repeat for each speaker that will need a crossover..

 

Well I guess it can get expensive then