depends on your overall setup. you may still have options to make it work.

For example... I run a 3way setup and haven't hooked up my new amps to go fully active yet. My HU allows me to run my 8's with a bandpass crossover, then I run a highpass out from the HU and have mids/ tweets on a 2 way passive crossover. I'm currently running my 3 way off a 4ch amp

If your HU or amp allows for a bandpass crossover you can run your 6.5 directly off the amp. then just use the mid/ tweet on the 3 way.

there's way to make it work but depend on your equipment capabilities. If you run a dsp, then it's just that much easier

need more details of your equipment/ plans for others to better hep you

 

Will there be any effects by running the 3-way crossover I just ordered in two way config only hooking up the tweeter and mod to it, then running that off 2 channels of the 4 ch amp, then running the remaining two channels with the 6.5 for speaks. I just am afraid of the unknown, for instance with running a 3 way passive crossover with only 2 speakers high and mid, cause any phase issues, or will this effect impedance in any way as the 1-way low end section of the 3-way passive crossover will not be populated with a speaker.

Thanks in advance.

 

Why do you want to run the midbass separate? If you have a three-way crossover now, just use it for all three speakers. Bridge your amp to 2 channels and feed the passive threeway more power. No point in splitting the mids and tweeters as passive from the midbass. If you're trying to use some rudimentary headunits TA by configuring it like that, I fully suggest getting enough amplification, a DSP and commiting to a proper three way active setup.

 

The reason I want to run the tweeter and midrange on 2.channels.and.the mid bass on the other 2 is because I have a dsp and would like to run these separate because of tuning.options i would Otherwise lack. I can tune only one setting if I bridge amp and feed the 3 way crossover as the dap setting would effect all 3 speakers. Like I mentioned I purchased the 3 way crossover instead of the 2 way on accident. If I run only 2 speakers (2-way) out of 3 ports.on thr passive crossover will it do anything negative like mess with the ohms or phase of anything. Since only 2 way are populated. On a 3 way crossover?