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If you are using CCS loaded parafeed finals, how is the parafeed cap value determined?
The only things I have seen are formulas for choke loaded parafeed finals.
I am actively biamping from 800 cycles 4th order LR with my CCS loaded SE 45 parafeed amp.
Should I just pick the best quality small uF cap available since I am not concerned with the low end Hz rolling off?
Follow Ups:
... the inductance of the output transformer primary varies over a wide range depending on frequency and signal level. The other problem is, the transformer losses (copper loss, eddy current loss, and core loss) are substantial enough that they must also be included if you are to calculate an accurate value for best bass extension.
For an active crossover, where you know there will be no deep bass, you can follow drsx's advice and set a first order highpass just low enough to not affect the crossover. You can even use that pole as part of the crossover.
An octave below the crossover frequency should be OK.
I can check it with an RTA & mic , then tweak the parafeed cap value if needed.
Thanks to all.
The L and the C will form a tank circuit (with the R's contributing) and it will resonate.
You want to keep the frequency of that resonance below the lowest frequency of interest.
I don't have the formula right now but I bet you could find it.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
.
Have Fun and Enjoy the Music
"Still Working the Problem"
"Should I just pick the best quality small uF cap available since I am not concerned with the low end Hz rolling off?"
I would guess yes.
You're not going to excite the resonance so just a cap large enough to pass your lowest frequency of interest into the reactance of the load (reflected and inductance) should be fine.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Basically you add the Z out from the plate to the impedance of the transformer primary, pick your rolloff frequency, and use
C = 1/(2 * pi * F * Z)
This will give you a good approximation.
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