Building passive crossover for bedroom system... confused

[Based]

I'm putting together a system for my room and I am confused about how to make the crossover.

I have 2 subs, 2 tweeters, and 2 mids. Is there a way to make a crossover for each tower that all 3 speakers (per tower) go into it and then come out of it as one channel (1 pos 1 neg)? How do I determine the final impedance if I do it? I know the math about creating filters for individual speakers with inductors and capacitors but I'm confused about doing it for 3 different speakers.

I know this isn't car audio but I'm not registered on a home audio forum so I thought I'd try here first.

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[dubstepper1000]

I'm putting together a system for my room and I am confused about how to make the crossover.
I have 2 subs, 2 tweeters, and 2 mids. Is there a way to make a crossover for each tower that all 3 speakers (per tower) go into it and then come out of it as one channel (1 pos 1 neg)? How do I determine the final impedance if I do it? I know the math about creating filters for individual speakers with inductors and capacitors but I'm confused about doing it for 3 different speakers.

I know this isn't car audio but I'm not registered on a home audio forum so I thought I'd try here first.

Well first off, you would have to use 3 different filters, with each input lead hooked together into one signal. Then you would need to get some high quality parts online if you are planning on making it from scratch (blue resistors for sure). Build 3 filters, LPF for the bass, unless it can't play really low tones without sounding bad, in this case, you might want to make it a band pass filter with a lower cutoff freq. of like 35 Hz. Use a bandpass filter for the mids, and HPF for the tweeters. I can help with the math of the components if you need, but it sounds like you know somewhat what you are doing. The only thing, its preferred to have the filter before the signal would be amped, which unless you want the signal to be mixed up, you would 3 separate stereos unless you know how to design your own stereo. So if you apply the filters to the output of the stereo, you would need components that are made to handle the higher current without producing too much noise.

 

[bubbagumper6 5,000+ posts]

The final impedance is frequency dependent. What you want to do is choose all the same impedance speakers. I.E. 4 ohm tweeter, 4 ohm mid, and a 4 ohm sub. Or like in my case I have a 8 ohm tweeter, two 4 ohm mids wired in series (which equals 8 ohms net), and an 8 ohm woofer (sub). Then the load on your stereo is always ~4 ohm (mathematically, not literally).

As far as actually designing the crossover goes, a good design program will help you a lot. I used one called Xover 3 Pro which allowed me to input the TS parameters of all the speakers and design a crossover around them. It displays the ideal response graph like WinISD which is helpful. Looks like this...

Once you have all your component values, go to partsexpress.com and order everything. (Keep in mind good quality components aren't cheap).

I hope you know how to use a soldering iron. I mounted all of my components on a small piece of plywood using a hot glue gun.

 

[Based]

So say I had a 4ohm tweeter, mid, then sub. I just wire each through their personal filter and then wire all the positives together and all the negatives together? Is the diagram in your pic wiring the speakers in series or parallel? I know how to wire subs in series/parallel and that series increases impedance and parallel cuts it in half, but I can't tell what's going on in that crossover.