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Discussion Starter · #1 ·
I installed a Kicker 6.5" woofer for a customer and am using the sub output from an XD700-5. The sub channel puts out 180W @ 4Ohms, but the sub handles only 150W rms so I have the gain set for a higher input voltage so as not to over power it, but amp only has a low-pass filter without any subsonic filter and these lower frequencies are killing this woofer.

I want to just add a capacitor to have a cut off @ 80Hz with an -18db to -24db slope. I have never built a crossover and I do not even know what type of capacitor to use in this application.

I need help from one of you SQ geniuses out there who has experience with building crossovers.
 

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not posible. a cap will only get you a 6db/oct slope.

if you want a steeper slope it takes alot more components.

18db for HP is 2 caps and a coil, for LP is 2 coils and a cap.
24db is 2 caps and 2 coils for either HP or LP.

Passive Crossovers, Capacitor and Coil Calculator
 

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could always put it in a tiny (critically damped) box to cut lows...
 

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Discussion Starter · #4 ·
Awesome. Is there a specific type of capacitor and inductor I should use for this application? Also, I am assuming I should mount all of this on a circuit board? Will I need a heat-sink? I know these are stupid, rookie questions, but as I mentioned before, I have never built a crossover network.
 

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Parts express has all the parts you will need and they should be able to help you get the right stuff the first time.
Building a Crossover at Parts Express

They also have a forum where you can ask for help.
Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com - Powered by vBulletin

They have very good prices on part, but the shipping is high, so try to get everything in one order so you don't have to eat the shipping charges twice.

I needed less then $4 worth of diods and resistors that weigh almost nothing
and had to pay $12.50 for shipping...
 

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Madisound.com is another good place for parts

Sent from my Motorola Electrify using Tapatalk
 

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As silly as it may seem, you're probably better off obtaining a inexpensive active xover. Designing a passive can prove costly if afterwards you find that the chosen cutoff frequency isn't optimal and you have to start over again. You could implement a active 2-way for much less in the end although you will only be using the high-pass. Something like an used MTX RTX01A should work fine and can be obtained very cheaply since most don't use outboards much these days.

Sent from my SCH-I500 using Tapatalk
 

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I also posted a reply to your post in the other forum. I also have to agree with a few of the members here. It is rare to have a 80 Hz passive crossover, let alone a 12 or 18 db slope. 80Hz and above is usually handled by midwoofers and HU or amps often have HP filters for this. Help us help you by explaining more what the rest of your setup is
 

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or simply try a small box.. 10min of work to save what..

But hey, what could I possibly know...
 

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I wouldn't bother Aaron.... sometimes help is not really wanted, just confirmation/validation of a cooky idea. Not saying that is the case of the OP, but once a person's mind is made up there's no use inf furthering.
 

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I wouldn't bother Aaron.... sometimes help is not really wanted, just confirmation/validation of a cooky idea. Not saying that is the case of the OP, but once a person's mind is made up there's no use inf furthering.
Quoted for troof.. :D
 

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to further complicate the issue is calculating the power handling capacity of the cap and any inductor if a higher order design is used. There is no easy solution to this seemingly simple question.
 

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Discussion Starter · #13 ·
or simply try a small box.. 10min of work to save what..

But hey, what could I possibly know...
1. I have already said your suggestion is hack

2. I am utilizing the customer's factroy enclosure and I only charged to install the woofer which she provide into the console where she wanted it - I did not charge her to hack up her factory enclosure nor did I charge to build one from scratch.

3. I already went over this - I asked how to build an active crossover, not for suggestions for hackalacious "10 min." fixes.

4. I would never take suggestions from a moron who utilizes a forum to build his ego by playing forum police.

"But hey, what could I possibly know..." I am sure that most people who have the misfortune of crossing life-paths with you ask themselves that same question.
 

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so your charging your client for not properly designing a system and just giving them what they want? you said you put the sub they provided in an enclosure, that's probably not even suited for that driver, because that's what the client wanted? did you inform the customer of the correct way to do things? that a properly designed enclosure should be designed and built for it? just doing a 'hack' job of making a passived crossover to fix the sound output isn't the way things should be done.
 

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so your charging your client for not properly designing a system and just giving them what they want? you said you put the sub they provided in an enclosure, that's probably not even suited for that driver, because that's what the client wanted? did you inform the customer of the correct way to do things? that a properly designed enclosure should be designed and built for it? just doing a 'hack' job of making a passived crossover to fix the sound output isn't the way things should be done.
You do realize your "beating a dead horse", right?:whip:
 

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so your charging your client for not properly designing a system and just giving them what they want? you said you put the sub they provided in an enclosure, that's probably not even suited for that driver, because that's what the client wanted? did you inform the customer of the correct way to do things? that a properly designed enclosure should be designed and built for it? just doing a 'hack' job of making a passived crossover to fix the sound output isn't the way things should be done.
Well well, another know-it-all - awesome! Do you know anything about what I did on the Jeep? Have you ever seen the factory 6" enclosure in the center console? I ask because it would seem, sir, that you are speaking out of your ass.

I did a 10W3 in a sealed enclosure behind the rear seats - that takes care of 80Hz and below. Why the **** would that little tiny 6" need to be playing 40Hz?

" did you inform the customer of the correct way to do things? that a properly designed enclosure should be designed and built for it?" Yeah? So I should have tried to sell her on a custom fiberglass enclosure to take place of the factory one (which already utilitizes ever square centimeter possible) so the little 6" could play the low frequencies that her 10" sub is already playing?? That would be awesome - $60 for the 6" sub and $600 for a custom enclosure to replace the one that she already has. That would have been a great way to eat up her budget.

The Jeep has little 4 X 6 speakers in front which do not handle frequencies below 100Hz all that well, so the 6" sub does a very nice job filling in the gap between the 10" sub and the 4 X 6's, however, it does not handle 40Hz all that well, and why the **** should it when the 10" does handle it?

"just doing a 'hack' job of making a passived crossover to fix the sound output isn't the way things should be done" Now that is interesting, I have never heard that crossing over a speaker to make it play in the range that you want it to play is hack. My God, you are a real genius now aren't you. You should go to Dynaudio and tell them what hacks they are for crossing over their mid-woofers.

It truly is laughable that you come on here telling me that I need to build a proper enclosure when you don't know **** about the factory enclosure's specs, nor do you have any clue what it would cost for the customer to pay me to fabricate an enclosure, nor do you have a clue about her budget.

Your willingness to defend your ******** is admirable, but you either need to take Aaron's **** *****, or learn how to breathe out of your nose because you are demonstrating signs of brain damage due to lack of oxygen.

 

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This thread took a turn for the worse.
OP, might I suggest you find your solution to your question another way or consider the options already presented.

Closed.

Bret
PPI-ART COLLECTOR
 
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