Mixing Xovers

Post by **bdubs767** » Thu Sep 20, 2007 6:19 pm

Is there any ill effects of mixing xovers...

Say your deck makes a 50hz HP Cross @ 12db slope and the amp makes a 50HP cross @ 24 db slope to make a total of a 50hz HP cross with a 36db db slope. My gut tells me that their has to be some ill effects with phase. But if you stay at 12 db incriments you'll still have 180 degree phase shifts, so it should work but somethings telling me I am missing some part of the equation here.

brenzbmr@sb · Post by **brenzbmr@sb** » Thu Sep 20, 2007 10:47 pm

yeah your gonna have some phase issues at the xover point.

for every 6db i believe is 90 degrees in phase shift.

Post by **Bfowler** » Fri Sep 21, 2007 8:14 am

hmmm, i might have to play with that....im running my crossovers on both my amps and deck.

Post by **bdubs767** » Fri Sep 21, 2007 8:18 am

Also...

THe xover will NEVER match up.

Like 50hz on the deck could be 51hz on the amp, which will Im guessing cause even worse phasing issues.

Post by **Bfowler** » Fri Sep 21, 2007 8:40 am

so lets use my bros system as a reference

i am using the rnet crossovers on the sub amp at 85hz. then also using the deck crossover at 60hz. what does that do to the phase? would it alter it all accross the board, or only at frequencys that are getting "double duty"

do you think the kenwood crossovers (which are didgital im gussing, no specs in the manual for how many DB/octave they are) are better then the XS amps crossovers?

something else i just realized. the xenon monoblocks crossover can't be bypassed or turned off.

Post by **VW337** » Fri Sep 21, 2007 1:53 pm

Digital XO's are digital so in reality there should be no phase alterations as they are not effecting an analogue signal which is where phase is present.

If you are stacking a digital and analogue XO together you should be safe however the slope may get a bit bumpy if not matched well.

Post by **bdubs767** » Fri Sep 21, 2007 2:09 pm

VW337 wrote:Digital XO's are digital so in reality there should be no phase alterations as they are not effecting an analogue signal which is where phase is present.

Hmm, but still doesn't it effect the phase once its back in the analog stage because that slope is present once the signal is converted into the analog stage.

VW337 wrote:If you are stacking a digital and analogue XO together you should be safe however the slope may get a bit bumpy if not matched well.

Be tough to match it exactly though...

Post by **bdubs767** » Fri Sep 21, 2007 5:11 pm

also errin is phase isnt effected in the digital realm how do units like the drz and h701 offer the ability to flip phase?

mrblob · Post by **mrblob** » Sat Sep 22, 2007 8:08 am

Couldn't you set your deck's xover to pass through -- no filter -- and use the amp's xover?

I also have a question --- if you have a deck LPF for your subs and you can't turn it off-- and your amp has it's own Xover -- Wouldn't it be a better idea to set the deck's LPF to the highest setting possible? Say 160 - 200 hz? And then let your amp''s LPF work at 60-80hz? Instead of trying to match them up? Or do I have my knowledge about crossover points all wrong? lol

Post by **bdubs767** » Mon Sep 24, 2007 11:36 am

since it made a ways down bump....

Post by **Bfowler** » Mon Sep 24, 2007 11:41 am

mrblob wrote:Couldn't you set your deck's xover to pass through -- no filter -- and use the amp's xover?

I also have a question --- if you have a deck LPF for your subs and you can't turn it off-- and your amp has it's own Xover -- Wouldn't it be a better idea to set the deck's LPF to the highest setting possible? Say 160 - 200 hz? And then let your amp''s LPF work at 60-80hz? Instead of trying to match them up? Or do I have my knowledge about crossover points all wrong? lol

nope, thats pretty much what i am doing. i have done it a little more though. my decks LPF is set to 80, and my Amp's LP is set to 60

Post by **VW337** » Mon Sep 24, 2007 11:43 am

bdubs767 wrote:also errin is phase isnt effected in the digital realm how do units like the drz and h701 offer the ability to flip phase?

Phase can be effected if directly targeted, however in a Digital XO it is just targeting frequency. In the analogue realm the phase is effected while adjusting the Frequency depending on the rolloff.

Post by **bdubs767** » Mon Sep 24, 2007 11:48 am

spank you...I might have to start having my 21 question again with you.

Post by **stipud** » Mon Sep 24, 2007 12:32 pm

mrblob wrote:I also have a question --- if you have a deck LPF for your subs and you can't turn it off-- and your amp has it's own Xover -- Wouldn't it be a better idea to set the deck's LPF to the highest setting possible? Say 160 - 200 hz? And then let your amp''s LPF work at 60-80hz? Instead of trying to match them up? Or do I have my knowledge about crossover points all wrong? lol

Yes, it's probably better to set the deck crossover as high as possible if you want to use the amplifier.