# Ideal Crossover,.. How to find ??



## randyc1 (Jul 20, 2011)

I have Dual Subs and small Kef satellite speakers , using REW how should i go about to find ideal crossover setting .

Is it simply by trial and error to find smoothest Overall FR or smoothest FR at crossover ??


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

You could first use REW to determine where the KEF sats start to roll out, then set the sub’s crossover frequency accordingly. If after that you get some raggedness, or a trough or peak, around the crossover frequency, you can try adjusting the sub frequency up or down a bit, and/or the sub’s phase adjustment.

Regards,
Wayne


----------



## randyc1 (Jul 20, 2011)

When checking where the Kefs rollout , where do i put the crossover ,... does the crossover affect the rollout point ?????


----------



## robbo266317 (Sep 22, 2008)

As Wayne says, remove the subs and do a sweep on the satellites only (full range ie 20 to 200Hz, no crossover) to start with and then measure just the subs.
This can be displayed in the one REW window and will show how much the two overlap. You can then pick a point in the overlap region to set the crossover. 
After choosing the appropriate crossover point you measure them as a system to see how well they work together.


----------



## randyc1 (Jul 20, 2011)

Ok so in the AV Reciever i put the crossover at 0 before doing the 20-200hz sweep with just the mains ,.. Right ?


----------



## robbo266317 (Sep 22, 2008)

If 0 is turned off then yes. 
I used the left channel and connected my mains, did a sweep and then swapped the wires over to the sub and ran the same sweep. I don't know if yours is active or passive?


----------



## randyc1 (Jul 20, 2011)

Maybe u can help me choose the best Crossover ,.. here is a Zoomed section of the FR around the Crossover at 1/12 smoothed, the colors are coded at top of graph


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

randyc1 said:


> Maybe u can help me choose the best Crossover ,


To do that we'd need a full-range graph with just the main speakers - front left or right.

Regards,
Wayne


----------



## randyc1 (Jul 20, 2011)

Wayne A. Pflughaupt said:


> To do that we'd need a full-range graph with just the main speakers - front left or right.
> 
> Regards,
> 
> Here you go, L+R crossover is at lowest -40HZ


----------



## robbo266317 (Sep 22, 2008)

The mains look like they start rolling off around 100 Hz and the sub around 50 Hz. 
I would try graphs at 60 Hz and 80Hz crossovers with mains and subs together. Unless you have one in-between as well.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Hey Randy,

Based on the graph, I can't see any reason not to go with the usual 80-90 Hz crossover frequency.

Regards,
Wayne


----------



## randyc1 (Jul 20, 2011)

Wayne A. Pflughaupt said:


> Hey Randy,
> 
> Based on the graph, I can't see any reason not to go with the usual 80-90 Hz crossover frequency.
> 
> ...


Well from the graph i posted earlier above , the smoothest FR graph actually came from a 80hz crossover . The higher i crossed , the less smoth it became ! 
Kinda suprised because of the small size of the mains 4", would have thought it would be better higher ?


----------



## dsime42 (Mar 4, 2011)

Tell the AVR that you don't have subs, or pull the power plug on the sub amp(s)


----------



## dsime42 (Mar 4, 2011)

Sorry I posted before reading the whole thread.
i.e. just after you were wondering where to set the crossover to get the full rand sweep on the mains.

What kind of sub rolls off the high end @ 50HZ?


----------

