Mismatched Impedances

[dwnrodeo]

I know that it is generally not a good idea to combine different speakers with different impedances, but can someone explain to me exactly why?
Is it because that the speakers will have mismatched levels when wired together? I was contemplating building speakers for my home audio setup,
and some of the speakers I have laying around are DVC 4, and 4 ohm.
Would it be possible to take a 4 ohm componenet set, a DVC 4 ohm 10" sub, and a 4 ohm 15" sub and wire them together like shown in the diagram
below without damage? I circled the two speakers in the middle to represent the one DVC 4 ohm sub. Also, where would I wire in capacitors and
inductors if building my own passive crossovers? Sorry for all the questions.

[stipud]

It's possible, but since their efficiencies don't match, they will not blend nicely. Also you usually need a crossover to split up frequencies between them... wiring them in parallel like that will just have everything play full range. Bleh.

[dwnrodeo]

Yeah, I was thinking of building some speakers using PG stuff I have laying around, but after reading up on passive crossover design I think I'm going to pass.

[dBincognito]

Get a power supply and run everything on it's own amplifier
Why not use PG stuff to power your home audio
You could run active off of the amplifiers

[12voltjunky]

old school bumpin'
you can get prewired/prebuilt crossovers from parts express without breaking the bank.

[The Golden One]

high end speaker companys make tower speakers with multiple speakers in them so its possable just more difficult im sure they mostly use impedance correction circuits to get the ohm's just right. i guess it all depends on how bad you what to do it because it can be done but with a great deal of research anything can be done you just may have to change a few things up.