Cross over help

hrdhtdvr

I want to first apologize if this has already been asked.

I just bought the Alpine CDA 9855 HU.
In the I personalize section of the website they ask if I have a 2 way or 3 way set up. What should I choose?

For speakers, I have a set of MMC460 in the rear and a set of MMC 6500 up front.

I looked at the diagram for the 3 way and it looks more like what I have. (Front Mid, front tweet, and Rear) The two way just shows front and back. My HU has a adjustable cross over.
I have the fronts set to 50hz 0db 12db/oct.
I have the rear set to 100hz 0db 12db/oct.

I currently do not have a sub installed.

1996blackmax

Go with the 2 way set up, this is what you want when you have front and rear speakers. The 3 way is if you are going to be running front speakers and no rears speaker (you can use a sub as well). This also gives you the abiltiy to run an active front stage. It's a nice feature if you want to bi-amp some components up front.

hrdhtdvr

Thanks for the advice. But, I am confused as to why to go with the 2 way instead of the 3 way. I am not doubting anything but I like to understand why you do something instead of just saying OK and doing it. I guess this sounds anal, but I see it as learning. Thanks again!

1996blackmax

NO problem, I am the same way. Let me try to explain it better. Some people run their system in a configuration where they have a sub, only use one pair of components/seperates (mid and tweeters) up front, and those are the only speakers they use for the mids and highs, no rear speakers. So the 3 way system is the tweeters, the midrange speaker, and the subwoofer(s). You will not be able to use the fader with this setup. When the Alpine head unit is configured to a 3 way mode you can delay the time, crossover slope, crossover frequency for each speaker (sub, mids, and tweeters), and I believe the Alpine also lets you adjust the output level. This is a very nice thing, I will probably give that a shot with my Eclipse head unit at some time to see how it sounds. So instead of using the crossovers that came with the component speakers you use the crossovers from the head unit.

Since you will be using rear speakers, the 3way setup does not apply to you. In your setup, the HU should be in the 2way mode. This will allow you to set up a crossover frequency for the sub (lowpass), and the midrgange (highpass), as well as use your fader. The supplied crossover with your components will have a cutoff frequency for the midrange (lowpass), and the tweeter (highpass).

Basically if you are using front and rear speakers you have to use the 2 way setup mode with the Alpine head unit, otherwise you will not be able to use the rear speakers.

hrdhtdvr

I feel RETARDED !!!!!!!!!!

I went to the Ipersonalize website and TA-DA, there it is in plain view. Front TW Front Woofer. No rear. (under 3 way)

hrdhtdvr

I have one more question. Crutchfield talked me into getting a set of Bass blockers at 300hz. Do I really need to use them since I have a active crossover in the HU? Currently, I have the rears set at 100hz 0db 12db/oct even with the fader all the way to the rear, I hear no distortion from the speakers. I would think that if I put the bass blockers in line, all it would do is cut down the bass, and hurt the SQ.

1996blackmax

Don't feel retarded, it takes a little time to learn this stuff .

As far as the Bass Blockers, send those things back. Crutchfield is usually pretty good about this stuff, and I do not know why person sold you those when the HU you bought already has crossovers (with both adjustable frequencies and slopes).

hrdhtdvr

Marie at Crutchfield said that "The HU's crossover network does not work without using the pre amp outputs." That is why I bought them. However, they are going back since that is untrue. Thanks for all the help.

1996blackmax

No problem, glad I could help .