can i use woofer from component speaker?

Today I picked up a pair of Boston Acoustics RC-620 woofers (neither the tweeters nor the crossover were included) at a Goodwill store for a few dollars. Can I use these to replace the factory 6.5" door speakers in my Saab 9-3? If so, do I need to use any additional electronics to filter out high frequencies, or anything like that? Thanks

You can use those, but you the woofers are made for midrange frequencies. You are missing the tweeters, so you probably wont get that many highs. If I were you I would buy a set of tweeters and a four channel amp that has adjustable crossovers. Then you would be set! You would get your highs and midrange, plus you would be able to set the crossovers on the amp to block out the frequencies that you need to.MECP Advanced

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Oh, I didn't realize that I could use a built-in amp crossover. That's great. If I buy a 4 channel amp with a built-in crossover, would I be able to set the front and rears differently? That is, if I have 6"x9" in the back, and these components in the front, could the amp handle the different crossover needs for each?

Most amps of good quality will have independent crossovers, so that you can use them for a tweeter and a woofer. You could use a 4 channel amp for the woofer and 6x9s but all of your highs will probably be coming from behind you that way. That is assuming you are getting 2 or 3 way 6x9s.MECP Advanced

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Most amps do not include a sufficient crossover to biamp a 2-way system, plus if you don't really understand what you're doing it is not an easy thing to set up.  You would need an amp with the ability to set both low pass and high pass at around 3KHz... not many amps around with that capability built in...Support the12volt.com

I guess that's true. You could add cap on to the tweeters. I think we have them at our shop at 5khz. But it doesn't sound like he is going to use tweeters anyways.MECP Advanced

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Well, my Saab has 3.5" speakers in the dash. Would I need to use tweeters with these 6.5" woofers in the door, or would the 3.5" take care of the high end?

Yea that may be fine. I would just try it out with what you have now and see how you like it and change something if you need to.MECP Advanced

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I don't have an amp yet. But if I set a 4 channel amp up to run the 6.5"s in the front and the 6"x9"s in the rear, do I have to do anything to the signal in front to filter out the highs? The dash 3.5" run off of the factory amp.

You may want to get a crossover... Just depends most of the crossovers on the amps are in between 20hz-400hz. If you wanted a little bit higher frequencies from the woofer than you may want want to buy one. Do you know the frequency response of those woofers?MECP Advanced

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