Passive Crossover Help

[pervertatoid 10+ year member]

So I'm looking at putting together a three-way component system. By "putting together", I mean it's not a component set, and therefore doesn't come with a three-way crossover. I don't have the money for any extra amps, so active crossover is out for now.

My question is this: How do I wire this? I found three in-line crossovers that would work for my system perfectly; one high-pass, one bandpass, and one low-pass.

Would this work?

Thanks in advance //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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[myvanpounds 10+ year member]

its just a little more difficult than that

those inlines are probbably only have a 6db rolloff

 

[helotaxi 5,000+ posts]

Depending on the drivers and freqs, 6dB might be fine. Might. The crossovers will wire in with their respctive driver. You then wire the series of crossovers in parallel to the amp.

There really is a lot more to getting a 3-wy passive system together than getting some speakers and adding some off-the-shelf filters and calling it good. I'd say look around at DIYAudio.com to get a better idea of what it takes to setup a 3-way passive system. It actually ends up being a lot more expensive and involved to do it even close to right than most people think.

 

[pervertatoid 10+ year member]

its just a little more difficult than that
those inlines are probbably only have a 6db rolloff

Depending on the drivers and freqs, 6dB might be fine. Might. The crossovers will wire in with their respctive driver. You then wire the series of crossovers in parallel to the amp.
There really is a lot more to getting a 3-wy passive system together than getting some speakers and adding some off-the-shelf filters and calling it good. I'd say look around at DIYAudio.com to get a better idea of what it takes to setup a 3-way passive system. It actually ends up being a lot more expensive and involved to do it even close to right than most people think.

The inline crossovers I was looking at getting are these (and similar):

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=266-120&scqty=2

I assume that by calling them "convenient 12dB crossovers", that implies they have a 12dB rolloff, though again, I'm assuming. 800Hz lows are for the midbass, 800-5k bandpass for the mids, and 5k highs for the tweeters. These frequencies fall within the ranges of supported frequencies of the drivers.

I'll check out DIYAudio, but is what I'm doing still wrong (or not necessarily "wrong", but a poorer-quality way)?

 

[helotaxi 5,000+ posts]

Not wrong, but much less than optimal. The passive filter should be designed for the drivers in question. Since you don't have control of the individual drivers atthe amp, you'll need the crossovers to do the level matching. Also, using the published frequency range of the drivers usually isn't the best way to go about things.

It will all work, but the results aren't going to be optimal. There's a lot more to setting up a passive system than plug and play. Overall it's much easier to setup an active system than to scratch build a passive one.

 

[///M5 10+ year member]

That would be a complete waste of money. From the original question I can tell you that I would highly recommend that you don't try this at all. Even a passive 2 way system is probably beyond anything worth attempting for you. You cannot just buy off the shelf components and have it work very well at all.

If you do attempt this, first do a 2 way system. You will have to start by investing in some measurement gear to at the least measure the impedance of each driver across the frequency range.