PLLXO - Am I doing this right?

[ujju3doc]

For a two way speaker, I want to make a 1st order PLLXO with 300 hz crossover point. My audio chain is as follows: Desktop PC> Asynchronous USB DAC> PLLXO > Lowpass and Highpass out> one Preamp before one powers amps for woofer and full range driver. So i will be using two preams and two power amps. Preamp for Lowpass section has got 100 k input impedance and 10 ohm output impedance. Preamp for the Highpass section has got 50k input impedance and 170 ohm output impedance.
In PLLXO calculator, should i put crossover frequency 300 hz in both Lowpass and Highpass sections or it should be different?
In the Highpass section should i use 50k (R preamp) as R1?

Can someone help and guide me please?

 

[planet10]

Only the high pass filter is dependent on the R<sub>in of the amplifier. Easiest if you use it as the R for the HP filter.

dave</sub>

 

[ujju3doc]

Using the Highpass amp input resistance, i got value for capacitor only. Hope i have done it right. So if i use the Ramp as R1 in highpass then only a capacitor is to be used in the high pass circuit. Am i right?

 

[planet10]

if you use the R_in then the entire HP filter is a single capacitor (althou you may have to parallel some to get the right value)..

dave