Crossover Related Question

Autor

Beitrag

abhi.pani
Inventar

#1 erstellt: 05. Jul 2006, 09:02

Guys,
Please let me know about this:

1. If there are two speakers (both are two way, and have the same drivers, cabinets etc...except the crossover), Speaker A has its tweeter crossed over at 12db/octave and speaker B has its tweeter crossed over at 6db/octave.
The MidBass driver is crossed over at 6db/octave for both of them.

1. What could be the audible difference in sound ?
2. Which speaker should sound better?
3. Anything else thats worth noting between the two speakers ?

Kindly let me know about this asap.

Manek
Inventar

#2 erstellt: 05. Jul 2006, 09:51

you mean one speaker has a 1st order roll off and the other has a 2nd order rolloff.....

One cant really pinpoint which will sound better as it depends on many variables like driver characteristics crossover frequency chosen, serial or parallel topology, baffle step compensation, active or passive design, etc etc etc....and all the things that designers do with crossovers.

Some swear by first order and some designers believe and use higher orders.

So to my mind its not a parameter to judge sonic quality.

Your dyns have first order crossovers dont they ?

Manek.

abhi.pani
Inventar

#3 erstellt: 05. Jul 2006, 10:06

Ya Manek my Dyns do have first order.

Ok, I will try to give you few more details that I know...

Speaker A: Crossover frequency 3100hz, Design Passive
Speaker B: Crossover frequence 2700hz, Design Passive

Topology I am not sure off but both have the same topology

Is it still not enough to conclude anything ??

Manek
Inventar

#4 erstellt: 05. Jul 2006, 10:09

no conclusion ......

deaf
Stammgast

#5 erstellt: 05. Jul 2006, 10:36

Dear Abhi Pani
Firstly with different x-overs the speakers cannot have the same enclosure.That is because the tweeter will have to be placed differently for both the speakers in relation to the woofer.The moment you make that one change, then it no longer is identical in any sense.
Deaf.

Behram
Ist häufiger hier

#6 erstellt: 05. Jul 2006, 11:00

Dear Abhi,

I can tell you one thing from experience. The human ear is most sensitive in that freq. range 2Khz - 3 khz. If at all this region is chosen as the crossover point the slopes should be chosen so that there is no hump in the overall frequency response or else the speaker will sound harsh ot squaky.

Given the parameters you described 12db/octave should sound better sonically considering that the hump is levelled or at the most it enters the trough region.

Regards.

Behram.

abhi.pani
Inventar

#7 erstellt: 05. Jul 2006, 11:07

Can anyone explain me what is the meaning of 12db/octave slope ? What could be its implication on music reproduction ?

deaf
Stammgast

#8 erstellt: 05. Jul 2006, 11:08

More than what type of slope is choosen electrically,the acoustic slopes of the two drivers should be identical.Only a correct acoustic handover between drivers will result in a good sound.I am of course assuming that the dips and peaks at x-over are at a minimum.However do keep in mind,just a respectable frequency response does not ensure a great sound.
Deaf.

Behram
Ist häufiger hier

#9 erstellt: 05. Jul 2006, 11:18

Abhi wrote

Can anyone explain me what is the meaning of 12db/octave slope ? What could be its implication on music reproduction ?

An Octave is typically double the frequency. Let me put it this way. Reference at 2 khz the lower octave is 1 khz and the upper one at 4 khz. Since reactive components are used in a crossover network (L & C)their reactance varies with frequency. A figure of 12 db/octave would mean that if the reactance at 2 khz is 0 db (ideally) it would be -12db at 4 khz. So eventually one would be hearing musical content 12 db down at 4 khz than what one would hear at 2 khz.

Still confused ?

Behram.

Sonic_Master
Stammgast

#10 erstellt: 07. Jul 2006, 12:40

hi abhi,
the crossover frequencies...and the driver rolloff is a very much related... IN general a driver can be crossed before the rolloff
i mean if a mid bass driver with a freq resp of 40 to 3khz with flat freq response and we have to check how fast it rolls of and then to see which order or crossover that you have to choose for it... if you choose a xover point which is chosen in the safe region then no problem but we need to consider even the phase response also....

Its a very long prcess in choosing the right points and the right drivers....

so if your crossover is done right with good drivers then your speakers sound well...

but prefered to go with the first order which are sonically very good... but higher the order you go more the problems you face...

cheers,
Sandeep