Hey all,
Looking to replace a somewhat noisy Active Crossover with a simple 2 way PLLXO. Did all the calcs and for my 100k input amp, came up with the value of resistors / capacitors for 1khz @ 2nd order. I would further like to have the ability to attenuate the High Pass as the Tweeter (compression driver) is quite a bit more efficient than the woofer on this open baffle (Selenium 220Ti - 2x Eminence 15A woofers). I could do an L Pad at tweeter, but would like to see if possible to do it at the line level.
First question is is it possible to just attenuate the HP with PLLXO?
Second question is before or after the tweeter PLLXO? (methinks before is best)
Third Question is what value pot should I use for the HP attenuation? (10k, 50k, and 100k Alps available)
Looking to replace a somewhat noisy Active Crossover with a simple 2 way PLLXO. Did all the calcs and for my 100k input amp, came up with the value of resistors / capacitors for 1khz @ 2nd order. I would further like to have the ability to attenuate the High Pass as the Tweeter (compression driver) is quite a bit more efficient than the woofer on this open baffle (Selenium 220Ti - 2x Eminence 15A woofers). I could do an L Pad at tweeter, but would like to see if possible to do it at the line level.
First question is is it possible to just attenuate the HP with PLLXO?
Second question is before or after the tweeter PLLXO? (methinks before is best)
Third Question is what value pot should I use for the HP attenuation? (10k, 50k, and 100k Alps available)
I usully adjust levekls with the gain controls on the amplifiers. Never had to attenuate the top. But for the bass amp i have, we added a 100k pot on the front so i suspect a series R would work.
That scheme would work with the top to, but since the input R on the Pre-amp is used as part of the PLLXO, the caps will likely need their value tweaked for different Rs.
Note that a 2nd order PLLXO is kinda “droopy”. I now try to design for first order PLLXO.
dave
That scheme would work with the top to, but since the input R on the Pre-amp is used as part of the PLLXO, the caps will likely need their value tweaked for different Rs.
Note that a 2nd order PLLXO is kinda “droopy”. I now try to design for first order PLLXO.
dave
Thanks Dave... I will just try it and see what it sounds like and looks like on REW...
But isn't a 1st order even more "droopy" than 2nd order?
But isn't a 1st order even more "droopy" than 2nd order?
1st order is a perfect Butterworth, with no feedback the 2nd order is not really a slope with a name.
It is not an issue but jyust what is. And almost impossible to do a high pass if the power amp impedance is too low,
dave
It is not an issue but jyust what is. And almost impossible to do a high pass if the power amp impedance is too low,
dave
Did you mean input R of the POWER amp? What does input R of the pre-amp have to do with PLLXO?
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