1. Not sure how you are getting that a passive crossover is going to cost you 80 euros. Most can be assembled for far less.This is getting interesting.
I want to think the sugestions already made.
lsiberian in fact I have readed those informations about bi-amping. But sometimes I miss some points.
I'm just going to discuss the disavantages.
1- If I go the bi-amp way, I would save money from one amplifier (aprox. 200 €). Great. But, I will need to spend on the passive crossovers. Maybe 80 € for both. That saves me 120 €. Also I will be loosing 2 outputs on the DCX, right?
I agree that 120€ is a considerable amount of money, with that I can almost build the rear speakers for a 5.1 system. But also look at this, I'm young, and certanly I will want to do more teaking and some upgrades in the future, going tri-amp (or 3 way fully active) I'm not going to loose the money spent on the passive crossovers. But I'm still considering any reasonable option.
2 - I completly agree that "one amplifier with twice the power versus two amps of half the power biamped is less likely to clip"
3 and 4 - I make JCD my words.
JCD by your comments I assume that you encourage the 3 way full acive, right?
Please, lsiberian and JCD (and others), don't be affraid to discuss more issues, better now then later when money is spent.
2.You can still manipulate the entire sound of your system with the DCX. You'd be giving yourself the ability to hook up your subs to the DCX. Meaning you could have a 4-way setup with the subs fully eqed.
3. Fully active is just as time consuming as making a 2-way upper module filter. I"m not talking about passive between your bottom driver and the top. Only between the tweeter and the midrange.
4. Don't forget that XLR cables aren't cheap either.
Ultimately the choice is yours.
But I would encourage to at least give the passive crossover a go. If anything it will be a valuable learning experience.
If this is your first project I still suggest you start with a simple 2-way build before you undertake this beast. I don't think stepping into this as your first project is wise. There is a lot to learn that you will want to get before you build your longtime main speakers.
Either way make sure you treat your cabinets with fiber or rockwool and that you brace the out of them.