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Discussion Starter #1
Okay, so remember how I tried to install a new HU into my Audiophile setup? Gave up, took it to an installer and they did it, but now the sub plays all frequencies thanks to the factory HU functioning as the crossover for the system and it's removed. They have supposedly ordered me some 1st order crossover coils at 80 and 70Hz, but no one has contacted me to let me know they have arrived.

So, I'm wondering - in the other thread I made about this you guys mentioned the 2nd order crossover that Parts Express sells. Obviously it doesn't look too hard to just make one of those things myself, I can be handy if need be. My question is exactly what parts do I need? I found some tables for calculating what type of coil and capacitor to use based on what you want the crossover frequency to be, but what else do I need? I couldn't find any info that tells how to build one - only lots of sites selling books that tell you how to build car stereo stuff which is more info than I need.
 

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Not to thread jack SVT4ME but I had a question about crossovers for SA_PYRO_NE too. What did you cross over your rear speakers at?

Sorry SVT4ME.
 

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Discussion Starter #3
Haha, that's okay. Let's all get our questions for Scott in here! Looks like he's the man of the hour. [:D]
 

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caraudioforum is being less useful it seems, people don't answer questions alot because the threads get pushed down the list so fast and alot of people just don't care. i'm looking for another forum but it's good to use for searching topics, they've had just about every topic you cna think of. by any way, first of all, i don't use rear speakers, but i built kick panels and then kept the stock speakers in the stock postitions and crossed those over at 100hz low pass. it sort of fills in the lack of bass upfront, the doors vibrate but not to the point where it sounds like distortion, i like how they are. if you want to crossover your rear speakers and jsust use them for bass 100z would do well also. second, to build your own crossover you need a board to solder on, you can get a couple for a few dollars from radioshack or just get all your needs taken care of from partsexpress.com , buy the inline crossovers premade is easier but more expensive. you can get what you need for about $22 shipped ( http://www.partsexpress.com/pe/showdetl.cfm?&User_ID=15520651&St=2600&St2=76656221&St3=79434715&DS_ID=3&Product_ID=6741&DID=7 ) if you build your own you have to make sure your crossover can handle the wattage you put through it. a simple 12 db/per octave slope will work for what you need. use use the page at partsexpress.com for what size caps and whatever you need, there website just went down so when it comes back up go to speaker building, then to crossovers, and then on the right side of the page look for crossover building or something like that. your sub should be 4 ohm but i'm not completly sure so you might want someone else to confirm that, also, being good with soldering will definately help. i'll be gone from friday to monday but i'll answer any questions you have as soon as possible, it will be finals week so i'll be a little busy with stuff and won't be able to do much on here. i'm glad i can help everyone.

- Scott
 

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Discussion Starter #7
Yes, thank you. The sub is 4 ohms, the guys at the stereo shop checked that for me. How can I tell that the crossover (if I make one myself) is capable of handling the wattage I put through it? I just realized I don't even know how much power the stock sub's amp makes. [rolleyes]

Good luck on your finals!
 

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Cross over at the input of the amp and you won't have to worry about how much power the crossover can handle. Either use passive devices or even better, an active electronic unit.
High power coils and caps are big and expensive, not to mention hard to find. I've already been down this road and gave up looking for the raw high power components. The low power versions are cheap and plentiful. Some electronic crossovers are surprisingly inexpensive also.
If you must use the high power type, buy them already made.

My two cents worth, for free.
 

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crossing over the input of the amp was my first suggestion but someone informed me that the input to the amp isn't through rca's and was through some other sort of wire coming from the hu, so trying to cross that over would depend on what ohm the signal is, which is probably 50 or more ohms. therefore it gets very complicated and difficult. that's why i think the passive crossover between the amp and the speaker is easiest. i've never built crossovers myself so i don't know much specific so you'll have to ask someone else for more specific questions or do some research sorry.

- Scott
 

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Discussion Starter #10
At long last, success! They gave me another coil to play with - and it didn't make one bit of difference. I realized at that point that SOMETHING had to be wrong, so I talked with my dad who's kinda good with electrical stuff and he helped me out. Turns out the whole reason I couldn't discern any difference in sound quality with the coil attached was thanks to some crappy connectors! They were the type that you crimp down, and a metal blade slices the wire's insulation. Well, the insulation didn't get sliced, only squished - so there was never any metal to metal contact. [rolleyes]

So I used some butt connectors with the new coil, and voila! It works. Not quite as good as before (I can still just faintly hear some vocals if I move my head in close) but good enough that I'm happy for now. Thanks again to everyone who helped out!
 
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