building my first crossover help

[raverx3m 10+ year member]

so i finally got the speakers i wanted and installed them.

itsa 95 integra 2 door

stryke audio 7" woofer in the door

i found a nice pair of BMW door mids and put them where my tweeters normally go

had some infinity EMIT ribbon tweeters. took the plastic case off and mounted on my a pillars.

im still running them with my alpine 2 way crossover.

the woofers and mids and what needs a crossover, the infinity tweeters come with their own crossovers already.

can someone help me on specs of the speakers and what frequencies should they be set at.

and also someone mentioned about 4700hz for the stryke audio.

i never built a crossover in my life, i taken many apart so i kinda have an idea of how it should go but not really...

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[raverx3m 10+ year member]

and also delay.

beeing on those spots should i reverse polarity of any speakers at all? never done that before either.

i know i could just buy a set of VR focal 3 way speakers and i can get them with a discount from the store but i didnt want to, i want to see if i can make this set of random components to sound good.

please dont tell me its another stupid idea because i dont give a sht what haters think.

if you can help then help if not then move on to some other topic.

 

[boogeyman 10+ year member]

Whoever told you 4700 HZ for the midbass.......Dont listen to them at all.........A rule of thumb I go by is to X-over no lower than 2 times the Fs of the driver.......As far as reversing the polarity its trial and error.

 

[raverx3m 10+ year member]

but for the locations specified what do you normally end up reversing?

i i remember reading about tweets in factory location(top door) you reverse both of them.

what would i need to test?

can a trueRTA and a laptop be enough to tune it?

heres what i was thinkin.

im still learning it

1 calibrate the microphone

2 connect pc to my stereo via aux in.

3 run a 20-20000 sweep to see the frequency responce of the system and where the dips and peaks are.

4 run sweep for each speaker to see where it naturally rolls off.

would that be ok if the tweeters have their own separate crosover? how would it affect everything else?

 

[boogeyman 10+ year member]

There are several different methods used to tune eqs. This is the one I use. An RTA is not needed if the steps are done correctly. This method uses crossovers and gain settings as the most important factor in tuning. I think the eq should be last in line when tuning. Remember after each step to write down your settings. If the sound gets worse, then you can go back to the previous step’s settings and start over.

1. Set all bands flat, as well as the head unit bass and treble.

2. Turn off the subs. Using music with a good bass line, run the highpass crossover up and down until the midbasses can play as low as possible without any distortion or excessive door panel vibrations.

3. Unhook the mids and tweeters, allowing only the midbasses to play. Listen to mono pink noise or a well-recorded song with a centered vocalist. Test CDs such as the IASCA test CD or Autosound 2000 Test CD 102 or 103 will work great. Listen to where the centered sounds are coming from. Then reverse the polarity of one midbass (Reverse the speaker wires coming from the passive crossover and going to the speaker, just flip the positive and negative wires. I usually flip the driver’s side speaker.) and re-listen to the test CD. If the sounds are more centered then keep it as is. If the centered sounds are more diffuse and un-locatable, then flip the polarity back to where it was originally.

4. Then unhook the midbasses and play the mids only and follow the same polarity and listening tests as before. Mark your best settings.

5. Do the same procedure for the tweeters.

6. When you have tested for the proper polarity from all three ranges of speakers, hook all of them back up with respect to each set of speaker’s best polarity. You can have any combination of polarity, such as all the midbass and tweeters straight and one midrange reversed.

7. Now you should have the correct “acoustic” polarity set within each set of speakers. Next is to set the acoustic polarity between the sets of speakers.

8. Listen to some very familiar music with a good range of sounds. Then flip both midbass’ polarity and listen again. Before you only flipped one midbass, now you are doing both at the same time. For example if the left midbass was reversed and the right was not before, now the left will be not reversed and the right will be. Listen to the music again. If the midbass is more powerful and full then leave the wiring as is. If the midbass sounds weaker and wrong then restore the wiring as before.

9. Perform the same listening tests while flipping the mids and tweeters, and use the wiring configuration that sounds the best.

10. If you have went though all these steps adjusting the polarity of the speakers then the system should sound really good without any eq adjustments. You might want to play with the gain adjustments on the crossover and/or amp to better blend all the speakers together.

this is from another member on another forum this really helped me out.

 

[raverx3m 10+ year member]

thanks for the responce mang great info.

i was actually looking to build a passive crosover( a bandpass to be precise)

and have more questions

1 how are the aftermarket 3 way systems designed? are all 3 drivers(hi,mid,bass) 8 ohm?

if so then how are they wired to produce 4 ohm total at the crosover.

2 im concerned about the midrange that i have(the OEM bmw) itsa 2.5' driver

the reason i picked that is because its the only one that fits without modification.

but i know nothing about it, and did not find any info online.

im assuming its somewhere around 15-25w of power. but i have no idea what to use as far as crossover points.

my personal thoughts were to make

lowpass at 900hz for the woofer

900hz-7500hz bandpass for the mid