What is Crossover slope 2 x 12 dB/OcT??

[Goodspeed]

hey guys i am new at this... my speakers have this slope 12DB>?? what is the slope for or do??? i hear that you can tune with this it is???

[Hyun]

if ur SPEAKERS got slope, that is probably referring to the passive crossover box, which crosses with a -12 decibel/octave slope. all this u can't touch, since it's a passive cross, unless it's a higher end one with some user-settings possible (it'll be in your manual).

 

and u're running passive right, so all the more u can't touch. u only can touch ur HPF of front speakers to blend with sub, and LPF of sub to blend with fronts.

 

if u active, then u can touch this cross u're talking about. it's the cross between tweeter and front door bass driver.

[Kwongwing]

Hyun,

If I am not wrong, if advanced enuf can actually modify the passive x-over

Don't ask me how though

[Lionheart7004]

Agree.. all these are electrical calculations only. Passive x-over can be mod.

[User12343]

the x dB/oct slope means that for every doubling (or halving) of the frequency outside the passband frequency, the signal gets x dB attenuated.

 

eg, if a crossover is designed such that the HPF and LPF is 80Hz @ 12dB/oct and 4kHz @ 12dB/oct respectively, it simply means if u were to pump a signal of 40Hz into the crossover, the signal at 40Hz at the output of the crossover gives an attenuation of 12dB down from the passband amplitude.

 

same as for the HPF portion, if u input a signal 8kHz, you get a 12dB attenuation. if input a 16kHz, you get a 24dB signal reduction.

Edited June 13, 2006 by User12343

[Hyun]

i'm just a newbie but perhaps we can mention some useful guidelines to help newbies tune.

 

i just read on my CDT's website that they recommend subwoofers to have a LPF of -12 or larger number. they do not recommend -6. i suppose they dont want the sub sound to spread out too much and i guess it's logical. but it might be useful to state these simple but obvious guidelines for all to learn.

 

the complex ones might be: i still dont understand this phase thing which happens at transition points. to judge whether the phase is correct, i suppose using ears is one way. what's the other way to determine your phase correct or not?

[Hungee]

Hi Bro ...

 

Kind people from Delphi ICE DIY forum will always point me to this website and ask me to read the slope lah phase lah etc up myself ...

 

http://www.bcae1.com/

 

see if this helps

 

Cheers

Edited June 14, 2006 by Hungee