Alpine CDA-9887 Active Xovers?

[Phlipbak 10+ year member]

Ok, well I keep saying where Alpine's 9887 has active crossovers.. well, it only has high pass for the front and rear outs.. well.. I have mids and tweeters on the way (ID OEM 6.5's, and Seas 27TAFNC/G's) and I was going to cross the mids from 70-3khz, and the tweets from 2.5khz-15khz, but how can I do this if it only has HPF crossovers for both channels...

My mids might not do so well receiving super high frequencies and my tweets might not do well receiving below 2500hz so what do I do?? Am I wrong about how the crossovers on the HU work?

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[xxBURT0Nxx 10+ year member]

Yeah you cross the LPF for the sub (highest freq for subs to play... probably around 80hz), then set the HPF for the mids (lowest freq for mids to play). The LPF for the mids will be the highest freq for mids to play, and then you cross the HPF for the tweets(lowest freq tweets will play). Obviosuly it will depend on your crossover slope which the actual lowest or highest freq the driver will play is. A mid crossed at 80hz will still play a 70hz tone, just quieter. Hope that makes sense lol

 

[Phlipbak 10+ year member]

Ok cool, but I don't think there is an LPF on the mid/front/rear (whichever you prefer) channel is there? Only LPF on sub preout I'm pretty sure.. correct?

 

[xxBURT0Nxx 10+ year member]

pretty sure it's like this... but i don't get mine in until monday so not 100%

Sub: LPF

Mids:HPF, LPF

Highs: HPF

 

[Phlipbak 10+ year member]

Thanks man, don't forget to let me know how it is..

Can anyone else chime in that knows?

 

[Jekku 10+ year member]

Sub: LPFMids:HPF, LPF

Highs: HPF

Correct.

Flip the switch on the HU chassis to 3-way.

I was going to cross the mids from 70-3khz, and the tweets from 2.5khz-15khz

Why? Cross the mids from 63Hz/12db - 2.5kHz/6dB, tweets from 3kHz/12dB and the sub from 50Hz/18dB from the starters and from there you can start experimenting the settings.

 

[Phlipbak 10+ year member]

Uh... that leaves a 500hz gap..

 

[Phlipbak 10+ year member]

And cross the sub at 50? Dude that leaves like no range for the sub.......... I have my subs now crossed at 80hz and they sound phenomenal

 

[xxBURT0Nxx 10+ year member]

It doesn't leave a gap... if you cross the sub at 50 hz with an 18db slope then at 25hz and at 100hz it will be 18db quieter than a 50 hz tone. That is why you can cross... but all speakers and cars are going to be different, so I would suggest crossing at 80 for the sub, 80-2.5k for the mids, 2.5k for the tweets, then adjust each one up and down, see if it sounds better or worse and do it that way. Also, you have to remember to be careful and not cross your tweets too low or your mids too high!

This is from the reading I have done and what people have told me...

 

[Phlipbak 10+ year member]

Ok cool thanks

 

[BEAVER.989 10+ year member]

Correct.Flip the switch on the HU chassis to 3-way.

Why? Cross the mids from 63Hz/12db - 2.5kHz/6dB, tweets from 3kHz/12dB and the sub from 50Hz/18dB from the starters and from there you can start experimenting the settings.

Bingo. You'll need to remove the head unit and flip the switch on the underside to 3-way mode.

You'll have to experiment with the settings, though. Don't be afraid of gaps. X-over's are like brick walls, there is a gradual roll off.

FWIW, right now I'm at the following...

sub-63/24

mid/lo-80/24

mid/hi-2k/24

tweet-2.5k/24

I'm still adjusting, though. It seems like everytime I make an adjustment it makes an improvement. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif