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post #1 of 9 Old 02-14-2020, 06:52 PM - Thread Starter
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Help with diy crossover build

im building a threeway crossover with 600watt input at 8ohms

my design to be as followed ( woofer input a 4ohms ) ( mids input at 4ohms ) ( highs input at 8ohms )

my intended crossover at 750hz an 6690hz

my driver selection is two B&C 10PLB76 10IN WOOFERS & TWO PRV Audio WG275Ph 1" Midrange 8 Ohm & ONE Visaton HTH 8.7 Horn 8 Ohm


to achieve this can i stack my capacitor in the prefured config

i need a capacitor at 37.5uf by stacking a

1.50μF 250v PulseX - Metallized Polypropylene Film Capacitor an a 36.0μF 250v PulseX - Metallized Polypropylene Film Capacitor
__________________________________________________ __________________________________________________ ___

an one capacitor at 4.2uf by stacking two 1.10μF 250v PulseX - Metallized Polypropylene Film Capacitor an two 1.0μF 250v PulseX - Metallized
Polypropylene Film Capacitor

__________________________________________________ __________________________________________________ ______

an one capacitor at 2.1uf by stacking one 1.0μF 250v PulseX - Metallized Polypropylene Film Capacitor an one 1.0μF 250v PulseX - Metallized

Polypropylene Film Capacitor
__________________________________________________ __________________________________________________ ___

id like to add 9db of attenuation to both my mids an my tweeter

but i dont know how to do that can anyone sudjest which parts from www.erseaudio.com id need

an were an how to place them in my crossover
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post #2 of 9 Old 02-14-2020, 08:54 PM
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You can't use those generic online calculators to design a xover. They assume perfect flat impedance which is never the case especially with a CD and horn and they don't factor in frequency response. To do it you need the actual measured FR and Z curves of the drivers in the actual enclosure.
Tha impedance of the attenuator will also need to be developed as a part of the xover design.

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post #3 of 9 Old 02-14-2020, 08:57 PM
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Have you measured any of these drivers or is this all based on simulations only?
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post #4 of 9 Old 02-14-2020, 09:03 PM
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Looking at the PRV data sheet there is no way they will load properly to 750Hz and should be crossed at more like 1500, the horns are far, far too small. Also, how did you plan to physically locate a pair of them?

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post #5 of 9 Old 02-14-2020, 09:48 PM - Thread Starter
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Quote:
Originally Posted by Samps View Post
Have you measured any of these drivers or is this all based on simulations only?
simulations
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post #6 of 9 Old 02-14-2020, 09:49 PM - Thread Starter
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Quote:
Originally Posted by A9X-308 View Post
You can't use those generic online calculators to design a xover. They assume perfect flat impedance which is never the case especially with a CD and horn and they don't factor in frequency response. To do it you need the actual measured FR and Z curves of the drivers in the actual enclosure.
Tha impedance of the attenuator will also need to be developed as a part of the xover design.
should i use somthing like soundeasy23
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post #7 of 9 Old 02-14-2020, 10:21 PM
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should i use somthing like soundeasy23
Yes, or Vitiuxcad. But you'll still need to measure FR and Z in box.

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post #8 of 9 Old 02-15-2020, 07:27 AM
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Xsim is another option for designing your xo. I’m not sure if it does 3-ways though.

Don’t worry about getting exact values for your caps. Just get the closest you can. 36 vs 37.5uF won’t make much difference. You can unwind inductors to get exact values but you need an LCR meter to test them (cheap on amazon).

First thing you need are the drivers, a measurement mic, an impedance jig, and a test cab. Once you get all the measurements you can start modeling crossovers. But don’t expect the simulations to be perfect. You’ll end up swapping out numerous xo parts until you find something that works. I have almost every value of resistor that PE sells just for testing.
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post #9 of 9 Old Yesterday, 11:56 PM - Thread Starter
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Quote:
Originally Posted by Samps View Post
Xsim is another option for designing your xo. I’m not sure if it does 3-ways though.

Don’t worry about getting exact values for your caps. Just get the closest you can. 36 vs 37.5uF won’t make much difference. You can unwind inductors to get exact values but you need an LCR meter to test them (cheap on amazon).

First thing you need are the drivers, a measurement mic, an impedance jig, and a test cab. Once you get all the measurements you can start modeling crossovers. But don’t expect the simulations to be perfect. You’ll end up swapping out numerous xo parts until you find something that works. I have almost every value of resistor that PE sells just for testing.
thanks
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