WHich one will win? Crossover ?

[RandyJ 10+ year member]

And some of yall seem tot hink that a x-over point simply cuts the signal off past a certain frequency, and that is not the case. As squeak said it is attenuated at a certain slope. Which means that after the point, the signal will begin to play less and less. At 12dB/octave, the signal will be attenuated by 12dB every octave.

120dB@50hz

108dB@100hz

96dB@200hz

 

[smgreen20 10+ year member]

All I ment was that others will now or could now pick apart everything I say, just because I left out what I tought wasn't relavent.

 

[JettaGLI 10+ year member]

I doubt it's being played fully.
For example; If 67hz is being played at an output level of 125db (very modest output for subs now-a-days), and you have a 12db/oct crossover set at 67hz, then 125hz (slightly less than 1 octave higher) would still have an output of ~113db. Which is clearly audible, and probably more output than your mids have at that same frequency. If 67hz plays at 135db, then 125hz will still be ~123db...which is pretty damn loud.

However, when you set the deck's crossover to 50hz, the slope becomes much steeper since you are using it in conjunction with the amp's crossover, hence the output at the higher frequencies is much lower.

So to correctly use my amps crossover, set my decks LPF to the highest level (125) and then use the amp?

 

[squeak9798 5,000+ posts]

So to correctly use my amps crossover, set my decks LPF to the highest level (125) and then use the amp?

Huh? No, I never said anything close to that. Set them however sounds best and however blends best with your stereo. If that means using your deck xover @ 50hz and the amp's xover at 67hz...then so be it.

There isn't a "right" or "wrong" thing here. Just whatever sounds best.

 

[JettaGLI 10+ year member]

Huh? No, I never said anything close to that. Set them however sounds best and however blends best with your stereo. If that means using your deck xover @ 50hz and the amp's xover at 67hz...then so be it.
There isn't a "right" or "wrong" thing here. Just whatever sounds best.

That kind of sucks, that you can't turn off the one on the deck. So if I set them both to 50, and the amp at 12db slope, and the deck has an 18 slope, what slope does that put me at?

 

[squeak9798 5,000+ posts]

That kind of sucks, that you can't turn off the one on the deck. So if I set them both to 50, and the amp at 12db slope, and the deck has an 18 slope, what slope does that put me at?

Don't worry about the slope. Just worry about the sound //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Set them however sounds best, and leave it at that.

And you don't need to have them set to the same frequency.

 

[thch 10+ year member]

I have the crossover on my deck and on my amps. WHich one overrides the other?
I have my amp LPF set at 67 HZ and when I bump my HU LPF up to 125 it plays up to 125 out of my subs. But when I set the HU LPF to 50, and leave my sub amp LPF set at 67, then the subs play at 67.

SO, I just want to confirm that whichever crossover is set higher will win? Or is there some other rhyme or reason to this crossover situation?

My goal is to use the amps crossovers and not have the deck get in the way. I can turn off the HPF on the deck, but LPF can't be turned off.

i know a bit about this subject, maybe i can help.

* slope adds but alters the cutoff frequency. slopes only add past the filter cutoff frequency correspoing to it.

* this is minimized if one filter is set to a much higher frequency then the other. a 1Mhz lpf to block RF will not affect a LPF at 50Hz in any real way, and is thusly ignored.

* the filters are designed to blend speakers together. if the woofers are overpowering the mids, then you either need to turn down the bass or buy better mids.

* if you have a situation where you want bass-heavy sound, maybe using both filters would be beneficial.

** some info is not 100% accurate, all of this assumes butterworth or lower Q filters and ignores chebychev or anything with stopband zeros. these are special cases not found in the vast majority of commercial equipment. some specialized DSP units and some esoteric passive crossovers use these types of filters.

 

[JettaGLI 10+ year member]

Man.. why does this have to be so difficult????? //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

I messed around yesterday and today. I turned off all the amps crossovers and just used the decks crossovers. HPF at 80 and LPF at 80. I thought it sounded good, untill I played some godsmack and Korn. Then everything sounded muddy. + my amp was getting too hot and the thermal light was coming on. So..... of course I turned the gain down. However, I lost a lot of bass and I knew my system was not hitting to its potential.

So, I started messing around. I turned the deck to 50 hz LPF and turned the amps LPF to 24 db slope and set the LPF to around 55-57 hz. This allowed me to get the bass out put that I was looking for in the Godsmack/Korn type of music and still hit hard on the rap tunes + my amp was no longer getting hot. I then turned off the sub once it set to maximum output and turned on the mid amp crossovers and turned off the decks HPF. I started at full volume 80hz HPF using the amps crossover (24 db slope) and went down in frequency untill I got distortion. I have them set at 67 HZ.

Now, when it comes to transition, I have a hard time telling if something is missing.

Does it sound like the way I have things set up is correct for the proper mid to low transition? It seems to sound good, but if you guys have some suggestions that maybe would allow me to fill a gap I am not hearing, let me have them.

Also, if the deck is set to 50 hz, and the amp is set to 55, what does that get me? Would it be tbetter just to set the amp to 50 LPF.

 

[thch 10+ year member]

you need to get some material that has some of this midbass and bass marterial. korn isn't the easiest music to sound good. in my last car, the song "justin" wouldn't play one of the notes in the song. the note was supposed to be a very prominant note too.

that seems fairly low, but without knowing what other speakers you have, well, i really can't tell.

all speakers are affected by the effects described by the T/S specs -- this means a door speaker will have low frequency rolloff as well, and a 12dB/oct filter may become acoustically a 24dB/oct filter, depending on where the crossover frequency is.

in your case you're attempting to optimize the system for maximum SPL with the ability to play intricate basslines. things that are not independent. in short you'll probably have to trade a bit of booming to get the system you want.

to make things worse, the human ear will adapt to its surroundings, meaning that if your tuning the car at moderate to high volumes (90 to 110dB+) you're ears will adjust and something that sounds ok now will not sound as good next time you sit down in the car and listen.

in the end, my advise is too buy a notebook, find short reference songs to test the system. "twist" by korn is pretty short. i'm sure there is at least one short rap song. test the songs and evaluate what is wrong with the sound. then change settings and wait a minute or so, then try out the new settings. also, if there is a "phase reversal" or 180degree phase shift or polarity reverse option for the subwoofers, try it as well. the mids may be too far away from the subs and may be canceling each other out at some bass frequencies.

 

[JettaGLI 10+ year member]

you need to get some material that has some of this midbass and bass marterial. korn isn't the easiest music to sound good. in my last car, the song "justin" wouldn't play one of the notes in the song. the note was supposed to be a very prominant note too.
that seems fairly low, but without knowing what other speakers you have, well, i really can't tell.

all speakers are affected by the effects described by the T/S specs -- this means a door speaker will have low frequency rolloff as well, and a 12dB/oct filter may become acoustically a 24dB/oct filter, depending on where the crossover frequency is.

in your case you're attempting to optimize the system for maximum SPL with the ability to play intricate basslines. things that are not independent. in short you'll probably have to trade a bit of booming to get the system you want.

to make things worse, the human ear will adapt to its surroundings, meaning that if your tuning the car at moderate to high volumes (90 to 110dB+) you're ears will adjust and something that sounds ok now will not sound as good next time you sit down in the car and listen.

in the end, my advise is too buy a notebook, find short reference songs to test the system. "twist" by korn is pretty short. i'm sure there is at least one short rap song. test the songs and evaluate what is wrong with the sound. then change settings and wait a minute or so, then try out the new settings. also, if there is a "phase reversal" or 180degree phase shift or polarity reverse option for the subwoofers, try it as well. the mids may be too far away from the subs and may be canceling each other out at some bass frequencies.

My system: 2 JL audio 12w6v2's, 1000/1 Subs at 55-57 hz

6.5 comp VR JL set (front)

6.5 coax VR set (rear) Both mids at 67 Hz by way of the 300/4