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TheeyaN
07-01-2009, 08:52 AM
This is the last (i hope) thing that is bothering me..

What is ''SLOPE''?

I have slope settings for subwoofer,it goes from 0db to -18db

And slope settings for components which go from 0db to -12db?

What is that? What does it mean? On which number should i set it on?

HU is pioneer

captainobvious!
07-01-2009, 10:02 AM
The slope represents how quickly the frequencies are cut before/after your crossover point.

Lets assume you have a Low Pass crossover set at 1Khz. When you set a slope at 18db it means that the level/volume of those frequencies drops off, or "slopes" off at a rate of 18 decibels per octave. The higher the slope number, the quicker those frequencies roll off and the less info you will hear below that crossover setting.
If you had used a 6db slope, it would roll off slower, so it would be at a rate of 6db per octave which means you will hear more of the frequencies below the crossover point.

TheeyaN
07-01-2009, 10:08 AM
Yes yes i think i understand what you are saying. Thank you for also making an example.

Tell me by your opinion what is the best way to set these slopes?

HPF and LPF will be on 80HZ.

For the SUB -12DB and for the components -6DB?

Would that be OK or would u sugest something diffrent?

PaulD
07-01-2009, 07:44 PM
6 dB/oct is way too shallow for typical door mounted mids. Try 18 and 18 or 12 and 18

TheeyaN
07-02-2009, 02:16 AM
The door octave is max 12

subwoofer octave is max 18

and that is how its set by default,so i should leave it that way?

PaulD
07-02-2009, 08:10 AM
if that's all you have, then yes. Can you pick different freqs for bass LPF and mid HPF ?

TheeyaN
07-02-2009, 09:37 AM
My sub options are next:

LPF from 50-200hz

Slope from -18 to 0

Sub volume level -24db to +6db


Components options are

HPF 50-200hz

Slope 0 to -12db

Speaker volume level 0 to -24

SomeDonnieDude
07-02-2009, 09:59 AM
Try your sub @ 80hz and your comps @ 120hz. If it sounds like there is a gap in the frequency range between those to freq I would lower your comps hpf until that gap is filled (to where it sounds good to you). If you feel that your comps can play around 80hz better than your sub I would lower your sub to like 70hz and of course lower your comps HPF as you go to close the gap.

If both sub LPF and comps HPF were both set at 80hz there would be cancellation, especially with only an 18db LPF and 12db HPF.

smgreen20
07-02-2009, 10:23 AM
If both sub LPF and comps HPF were both set at 80hz there would be cancellation, especially with only an 18db LPF and 12db HPF.

Do tell. That's like saying having a left side and a right side things will cancel or if you have two subs things will cancel.

You will probably never hear it if it did happen due to the subs overpowering the mids. When things become out of phase is when you'll get cancellation. It could, as well, mess w/the imaging.

And note, for very 6dB/octave slope you choose it changes the phase of the speaker by 90 degrees.
6dB= 90
12dB= 180
18dB= 270
24dB= 360

TheeyaN
07-02-2009, 10:36 AM
I also have PHASE changing.. Normal and reverse ^^


And who should i listen to now? I was thinking about setting HPF and LPF both to 80.

My mids can surely take that, Alpine SPR 17S,powered with Alpine PDX 2.150 =150 rms per chanel.

TheeyaN
07-02-2009, 10:39 AM
12dB= 180
18dB= 270


If i set it like this there wont be cancelation right?

TheeyaN
07-02-2009, 02:16 PM
Heeeeeeeeeelp ^^

Every day i am learning something new about car audio,and every day i am more confused lol!

SomeDonnieDude
07-02-2009, 03:19 PM
"Do tell. That's like saying having a left side and a right side things will cancel or if you have two subs things will cancel."

You are correct, you might not notice it. But also depends on how strong your sub stage/mids are. I am referring to the front and sub stage overlapping. I've played with phasing and usually second guess myself so much as to what I hear I just leave it alone haha.

It was early in the morning when I typed that lol. I think the word I was looking for was overlap, not cancellation.

TheeyaN
07-02-2009, 03:52 PM
WTF..

So what is the point?

What should i do?

What is happening?

Who are this people

Where are you taking me



LOL!