Filter different orders?

emigrante · Apr 23, 2009, 10:02 AM

hi

i'm new @ using the kx-software. my english is not very good, so
i hope everyone understands my problem.

i would like to put a subsonic filter to my subwoofer.
unfortunately there are only 2 types of filters.
the crossover 2th und 4th order, which is not practical, because
you only can choose 40 hz @ 12/24dB. the other one is the eq-filter
with this "Q-factor" which does not make sense to me. by the way you can
only choose 20hz which is sometimes a bit to high.
i do not understand how this Q-factor works.

so my question is: is it so difficult to programm
a filter in which you can choose a frequenz from 10 to 20.000 hz,
an choose the slope from 6 to 24 dB?
does somebody work on it? does it make sense to wait for it?
or should i look for other solutions ?

i hope somebody can help me.
thanks for your time and reading !

greez,
tim

stylus02 · Apr 24, 2009, 05:16 AM

the eq- lowpass works well. you should split the signal into 2 pathes. give one path into the lowpass (to subwoofer) and the other into a eq- highpass (to mid/high speakers). set both frequencies to same value. the q- factor means the amplification of the frequency you have choosen. you can boost the bass extremely, when q is high.

stylus

emigrante · Apr 24, 2009, 11:49 AM

danke/thanks

but this was not my question.
a need a highpass for my subwoofer, so it works like a subsonic.

( gerne in german per pn

)

stylus02 · Apr 24, 2009, 01:22 PM

let's try in english again (could interest all kx- users in the world

). i had to read about a subsonic- filter: it's a highpass with preferable high slope. the kill of lowest frequencies should protect the subwoofer from high ampitudes. i knew the term "rumble filter" or "lowcut filter". you can use the eq- highpass with low setting the cutoff. if i'm right it's a second order biquad. this is good enough. also try the q- factor to boost or cut the amplitude of cutoff- frequency. (it virtual changes the slope of the filter)
if you want cut high frequencies too, because your subwoofer has no build-in lowpass, you have to put the eq- lowpass after the highpass. all in all you get a bandpass- structure with a great variable range (better that a fixed bandpass)

stylus

emigrante · Apr 24, 2009, 01:52 PM

yes i know, but the lowest frequenz, which you can choose is 20hz, i think.
thats too high. and this q-factor is a horror.

by the way: i need 6 dB filters also.

stylus02 · Apr 24, 2009, 02:46 PM

i think this could help you. (german tread)

Subsonic Filter- was macht er genau? - Hifi Basiswissen / Fachwissen - CarHifi Forum / Autohifi Forum / Hifi Forum

also take a look at earlier treads. some people have made plugins for multi-speaker setups with crossover filters, latency compensation and more.

again, the cutoff- frequency means the frequency, where the signal amplitude goes down -3db. of course lower frequencies have more loss on amplitude, if we look at the highpass. you can imagine the slope as a rise of a mountain. (there are no real filters with infinite slopes.) the mountains body is the frequency- range which can pass. everthing around it you will not hear.

and here we have a nice rendering of a 12 db highpass.
http://www.beis.de/Elektronik/AudioM...FRHighPass.GIF

to come back to your wish to set lower cutoff- frequencies than 20 hz. it's not really useful to to this, because the effect becomes smaller and smaller, if we stay on a 12 db highpass. the effect on 6db highpass would be smaller again.

conclusion: we need more than 2 orders to have higher slope. you can try to attach more highpass- filters in series to increase the order of the filter- structure.

stylus

emigrante · Apr 25, 2009, 06:11 AM

ähm. i know what a subsonic filter does.
and thats the point. a subsonic @ 40 or 20 Hz does not make sense, becuase
it cutts to much from the higher frequenzes.

36 dB @ 10 or 15 hz would be the optimum. anyway, the 6db and 18db filter
is also missing.
and i knwo the point with the -3db. it is the piont where the maximum
signal-power goes down by a factor (in german) "wurzel2".

so to clarify the situation:
i do not want to set a 6db subsonic!
the 20hz is to high for me. i would like to set it @ 10 or (max) 15hz but
with 24 or 36dB.

but a 6db HP crossover would be in some situations very good for the
tweeter e.g.

thanks for your help !

greez,
tim

Apr 23, 2009, 10:02 AM	#1
emigrante DriverHeaven Newbie Join Date: Apr 2009 Posts: 4 Rep Power: 0	Filter different orders? hi i'm new @ using the kx-software. my english is not very good, so i hope everyone understands my problem. i would like to put a subsonic filter to my subwoofer. unfortunately there are only 2 types of filters. the crossover 2th und 4th order, which is not practical, because you only can choose 40 hz @ 12/24dB. the other one is the eq-filter with this "Q-factor" which does not make sense to me. by the way you can only choose 20hz which is sometimes a bit to high. i do not understand how this Q-factor works. so my question is: is it so difficult to programm a filter in which you can choose a frequenz from 10 to 20.000 hz, an choose the slope from 6 to 24 dB? does somebody work on it? does it make sense to wait for it? or should i look for other solutions ? i hope somebody can help me. thanks for your time and reading ! greez, tim

Apr 24, 2009, 05:16 AM	#2
stylus02 DriverHeaven Lover Join Date: Jan 2008 Location: germany, sb0090 Posts: 158 Rep Power: 0	Re: Filter different orders? the eq- lowpass works well. you should split the signal into 2 pathes. give one path into the lowpass (to subwoofer) and the other into a eq- highpass (to mid/high speakers). set both frequencies to same value. the q- factor means the amplification of the frequency you have choosen. you can boost the bass extremely, when q is high. stylus __________________ http://freenet-homepage.de/stylish-s...xas/index.html

Apr 24, 2009, 11:49 AM	#3
emigrante DriverHeaven Newbie Join Date: Apr 2009 Posts: 4 Rep Power: 0	AW: Filter different orders? danke/thanks but this was not my question. a need a highpass for my subwoofer, so it works like a subsonic. ( gerne in german per pn )

Apr 24, 2009, 01:22 PM	#4
stylus02 DriverHeaven Lover Join Date: Jan 2008 Location: germany, sb0090 Posts: 158 Rep Power: 0	Re: AW: Filter different orders? let's try in english again (could interest all kx- users in the world ). i had to read about a subsonic- filter: it's a highpass with preferable high slope. the kill of lowest frequencies should protect the subwoofer from high ampitudes. i knew the term "rumble filter" or "lowcut filter". you can use the eq- highpass with low setting the cutoff. if i'm right it's a second order biquad. this is good enough. also try the q- factor to boost or cut the amplitude of cutoff- frequency. (it virtual changes the slope of the filter) if you want cut high frequencies too, because your subwoofer has no build-in lowpass, you have to put the eq- lowpass after the highpass. all in all you get a bandpass- structure with a great variable range (better that a fixed bandpass) stylus __________________ http://freenet-homepage.de/stylish-s...xas/index.html Last edited by stylus02; Apr 24, 2009 at 01:42 PM.

Apr 24, 2009, 01:52 PM	#5
emigrante DriverHeaven Newbie Join Date: Apr 2009 Posts: 4 Rep Power: 0	AW: Filter different orders? yes i know, but the lowest frequenz, which you can choose is 20hz, i think. thats too high. and this q-factor is a horror. by the way: i need 6 dB filters also.

Apr 24, 2009, 02:46 PM	#6
stylus02 DriverHeaven Lover Join Date: Jan 2008 Location: germany, sb0090 Posts: 158 Rep Power: 0	Re: AW: Filter different orders? i think this could help you. (german tread) Subsonic Filter- was macht er genau? - Hifi Basiswissen / Fachwissen - CarHifi Forum / Autohifi Forum / Hifi Forum also take a look at earlier treads. some people have made plugins for multi-speaker setups with crossover filters, latency compensation and more. again, the cutoff- frequency means the frequency, where the signal amplitude goes down -3db. of course lower frequencies have more loss on amplitude, if we look at the highpass. you can imagine the slope as a rise of a mountain. (there are no real filters with infinite slopes.) the mountains body is the frequency- range which can pass. everthing around it you will not hear. and here we have a nice rendering of a 12 db highpass. http://www.beis.de/Elektronik/AudioM...FRHighPass.GIF to come back to your wish to set lower cutoff- frequencies than 20 hz. it's not really useful to to this, because the effect becomes smaller and smaller, if we stay on a 12 db highpass. the effect on 6db highpass would be smaller again. conclusion: we need more than 2 orders to have higher slope. you can try to attach more highpass- filters in series to increase the order of the filter- structure. stylus __________________ http://freenet-homepage.de/stylish-s...xas/index.html Last edited by stylus02; Apr 24, 2009 at 03:23 PM.

Apr 25, 2009, 06:11 AM	#7
emigrante DriverHeaven Newbie Join Date: Apr 2009 Posts: 4 Rep Power: 0	AW: Filter different orders? ähm. i know what a subsonic filter does. and thats the point. a subsonic @ 40 or 20 Hz does not make sense, becuase it cutts to much from the higher frequenzes. 36 dB @ 10 or 15 hz would be the optimum. anyway, the 6db and 18db filter is also missing. and i knwo the point with the -3db. it is the piont where the maximum signal-power goes down by a factor (in german) "wurzel2". so to clarify the situation: i do not want to set a 6db subsonic! the 20hz is to high for me. i would like to set it @ 10 or (max) 15hz but with 24 or 36dB. but a 6db HP crossover would be in some situations very good for the tweeter e.g. thanks for your help ! greez, tim