FMOD Crossovers not working??.... tweets are playing mid/lows!!! static with HPF

[WOT]

Im having a problem with the first part of my install. Im waiting on my substage and midstage amps so I thought I would install my tweets and there own amp last night. They are selenium ST350 tweets, and to let them only see 2500hz and above, I have a pair of these inline with my rcas

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=266-288

They dont work or something else is wrong here, because when I fired it up, low volume, there is a CONSTANT static noise, even at zero volume, its faint, but you can hear it, static volume doesnt increase the volume is increased.

BUT the real problem, is that the seleniums are playing the mid notes, possibly lowes.

Ive got a Pioneer premier 860mp deck so its got great sq options, I noticed though, that I can get an audible difference in my tweets (there the only things running) when I play with 1.25khz and 2khz, which shouldnt even be getting to my tweets.....

So I swapped out the cheap amp that was running them (scoche 2 chanel, 35rms @8ohm/tweet) to a DUAL 4 chanel, bridged the chanels and still, the static is there, and the tweets are still playing notes they shouldnt be with the FMOD inline

WIth the dual installed I flipped the switch on it from "FULL PASS" to High pass, and the static gets LOUDER, switch is down to Low Pass, and the noise virtually goes away to the ear.....

I also tried a different set of rca's that were supposed to be for my mid amp, and that didnt change anything. Ground is fresh, secure and tight just did it.

Im really stumped on whats causing this. Any help appreciated

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[WOT]

Or maybe I have the FMODS installed wrong. I have them at the end of my rcas, the amp end, so its the FMOD that I am pluggin into the amp, just thought maybe its intended to be placed at the headunit end of the rca's?

Im stumped here, I dont get tweeters

 

[WOT]

And do I have this fmod piece installed in the right place, or does it not matter where inline of the rca it goes, or does it belong on the headunit side.

I do have a set of PG rsd crossovers, would I be able to run the speaker wire through that input, and only use the tweeter output of the crossover? I dont know what the rsd tweets crossover is though in that crossover

 

[WOT]

Can you explain to me what he meant by using my headunit as the only crossover though and removing the FMOD's? Id "like" to get rid of the noise, but it isnt a huge bother. The tweeters sound rather harsh though, no matter what tuning adjustment I do from 1.25k-15k. They just always seem scratchy/harsh if you try and give them some volume.

Mind you the tweets and tweet amp are all I have installed, maybe they will sound better once I get my 6.5's running, but they just seem to have a pitchy/scratchy sound to them.

Would polarity cause that? Id like to make them sound nice

The amp is set to fullpass, gains almost completely down, 12db slope on the headunit, no bass boost settings, 1.25K-15K hz in the headunit are all in the -3 to -5 area, but the tweets still sound scratchy / way to high pitched and not pleasant on the ear....

 

[DidUHearThat? 10+ year member]

 

[DidUHearThat? 10+ year member]

1) The part you linked to is a 2500 hz LOW PASS. If that's what your using for your high amp, you bought the wrong part. You needed a 2500 hz HIGH pass, not low pass.

2)The "static" is probably either alternator whine or amp gain hiss from mismatched gains. Is your head unit properly installed? Check the ground on your head unit.

3)What is the source "sound" your playing "notes" that you think your "playing" 1.25 khz? Are you using test tones or are you just messing with the eq?

4)What are the mids your using? Your not just using tweeters by themselves are you? Tweeters by themselves should be harsh and bright.

Remove the FMOD's. Set your xrossover to High pass at 2.5 khz. Either on the HU amp or both.

 

[DidUHearThat? 10+ year member]

Can you explain to me what he meant by using my headunit as the only crossover though and removing the FMOD's?

Who are you talking to here?

 

[WOT]

****it, I freaking did buy the low pass 2500 hz filter. I guess that solves one problem, god ****it.

Is there any reason is still always sounds harsh/scratchy? Or would me buying the wrong part be part of it......

And yes, as of this second, ONLY the tweeters are installed, mids/subs are all installed, but I am waiting for the return of the amps back from repair.

So I have to buy this then eh

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=266-286

So a high pass 2500hz filter, only lets 2500 and ABOVE play through the tweets, and low pass only lets the tweets see anything below 2500hz?

Thats weird since I was able to hear an audible difference when adjusting above 3000 aswell.....

What the hack is up with that!!

You say to remove the FMOD, I would like to, but I would only like my tweets to see above 2500. My amp only has crossover to 500hz, and my headunit doesnt have anything to isolate what the tweets play

Anyway I can make this work?

 

[DidUHearThat? 10+ year member]

And why the fvck are you using PA tweeters in your car?

 

[DidUHearThat? 10+ year member]

****it, I freaking did buy the low pass 2500 hz filter. I guess that solves one problem, god ****it.
Is there any reason is still always sounds harsh/scratchy? Or would me buying the wrong part be part of it......

And yes, as of this second, ONLY the tweeters are installed, mids/subs are all installed, but I am waiting for the return of the amps back from repair.

So I have to buy this then eh

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=266-286

So a high pass 2500hz filter, only lets 2500 and ABOVE play through the tweets, and low pass only lets the tweets see anything below 2500hz?

Thats weird since I was able to hear an audible difference when adjusting above 3000 aswell.....

What the hack is up with that!!

You say to remove the FMOD, I would like to, but I would only like my tweets to see above 2500. My amp only has crossover to 500hz, and my headunit doesnt have anything to isolate what the tweets play

Anyway I can make this work?

Yes, that's correct. You need the 2,500 hz high pass. That allows the "highs" to "pass" and blocks the lows.

You didn't answer my questions. What are the mids you will be using? What is the source sound you were playing? What were you "adjusting above 3000 as well? Do you mean the eq?

The fmods are only 3db per ocatve crossover slopes. So it will take a while for them to completely block everything below 2,500 hz. In your case they were tyring to block everything above 2,500, but only at a 3 db per octave slope. So there was still plenty of 3000 hz going thru them. A full octave up would be 5,000 hz, and even then it will be only 3 db down.

When you get the right part, HP, it will be reversed. At 2,500 hz, a full octave down will be 1.25 khz but still only 3 db down, and only 6 db down at 625 hz.

You can use two of them inline (per side) to acheive a faster slope of 6 db per octave.

 

[WOT]

Because I like it loud and heard form a few others on here that they screamed and sounded great on little wattage, I was lacking a little in the highs I thought with 4 6.5's PS rsds in the doors. Was worth a shot

Need help getting them to sound right though

Id imagine getting the right fmods would help lol, but eliminating them would work aswell......

 

[WOT]

And the Fmods are 12db/octave actually

The source sound I was playing was simply a high pitch songs that I have, nothing perticular, just going to ear sound, is there something that works better?

 

[DidUHearThat? 10+ year member]

Oh, you can remove the fmods, set your crossover to the highest it will go (500 hz) and it should work, but you run the risk of blowing the tweeter if you give it too much power. Keep the volume very low and it should be fine. Also adjust the bass settings on your HU to as low as it will go. -12 db Bass

Turn the highs up as high as they will go: +12 High.

That will at least let you know if this all works right.

 

[WOT]

Well I will have the other amps back by monday at the latest, so should I buy the 2500hz high pass fmods? Or is there another way to do it, everyone keeps saying i can do it with just my headunit, but I dont see how, other than just manipulating the eq like you said, but that will definetely fudge my mids tuning when there back in. FMODS where the cheapest 12db/octave solution i could find, with good reviews

ANd for the test sound, what do you recomend

 

[DidUHearThat? 10+ year member]

I was just curious what you meant by hearing 1.25 khz. I wasn't sure if you meant test tones or music.

Any high quaility music is fine. I like to use female vocals on a clean recording like Etta James or Rosane Cash. Not distorted Death Metal or rap.

Your headunit has the option to "biamp" which should allow you to set the internal crossover of the RCA outputs to around 2.5 khz - 3 Khz.

But that won't work for you because you also need the full range outupts for the PG comps. You can set it up just to test the tweeters then reset everything back.

Yes, if your going to have a seperate amp for the super tweeters then you'll want the High Pass 2,500 hz FMODS.

Or you might consider a higher crossover point like 6,500 hz - 10, 000 hz to really let them work as "super tweeters".

http://www.hlabs.com/technical/crossovers/page2.html

http://www.hlabs.com/technical/crossovers/