# ? best crossover for Rockville SPG88



## dreadknot (Jun 9, 2017)

whats a good crossover point to set for these from the receiver i was going set to 50hz, my current config is my fronts are at 70hz an 

my center at 60hz , would 50hz on these Rockville SPG88 for use as sides an a pair set at 60hz for rears be good i'll be driving 

each set with a crown xli 800 at 200watts a channel just like my fronts an center are
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this was my previous speakers preferred config because my subs are in the back (minus the amp power old loadout an emotiva A-500 80watts per ch) ( current loadout is 200watts a channel )

an i feel they blended better back to front , but with new speakers in mix that isn't aways the case as with my current duel 8in bics in front an center

my previous surround speakers set were all 6.5in polks set like this 50hz on front 60hz center 40hz on surrounds an 

100hz lowpass on the subs 

my current planed config is ( currently own PL-89 fronts at 70hz an two PL-28II centers at 60hz an ( Rockville SPG88 for sides at 50hz yet to be powered 

i plan to get a 2nd set of Rockville SPG88 an a as rears at 60hz both the sets to be driven by a crown xli 800

im still reworking my sub build


so an any thoughts on crossover point an speakers positioning

i also plan to build so bigass acoustic bass trap at 6ft by 3ft by 6in thick

will take pixs when i have a better camara


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

Speakers like that typically have a very high roll-out point, meaning the frequency at which the bass starts dropping. Hard to speculate without seeing some measurements, but the drop-point could be as high as 125-175 Hz. A crossover setting at 50-60 Hz will leave a big hole in system response.

Regards,
Wayne


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## dreadknot (Jun 9, 2017)

when you say very high roll-out point do mean were the bass starts to fade in output before it would blend with my subs


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

Yes.

Regards,
Wayne


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## dreadknot (Jun 9, 2017)

thanks sometimes i dont get the audio linguo ya think a good startin point would 150hz


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

I’d suggest taking some measurements to see where the lows start falling. If you don’t have REW, get some graph paper and manually plot the dB level of 1/3-octave tones from say, 500 Hz down. Once you plot a frequency response graph that you can look at, you’ll be able to determine where to set the crossover.

Here are 1/3-octave frequencies from 500 Hz:

500
400
315
250
160
125
100
80
63
50
40

You can download the test tones here.

After plotting, you should have a graph that looks something like this:


https://www.hometheatershack.com/fo...pb10-isd-takes-few-contenders-svs-lgrm-2-.jpg


Regards,
Wayne


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## BP1Fanatic (Mar 28, 2011)

My AVR sets the crossover 100hz for the LCR's and 120hz for the surrounds. I'm using 80hz on all 8 speakers.


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