Preamp low pass filter
In message , Jim Lesurf
writes
However you may not actually want that. :-)
Personally, for active filtering, I'd tend to prefer using a LPF, then
creating a HPF output by subtracting the LPF output from the input. The
result if you keep the levels matched is a LP and HP pair of signals whose
vector sum always equals the input. Thus the combined result shows no phase
errors due to the filtering.
For the actual filters I tend to lift the basic designs from the Active
Oh yes, I quite agree, a complex phase-compensated crossover has only
one advantage: it does help keep down vertical lobing problems. As
Arnie has also said, it does also depend on the inherent amplitude and
phase response of the drivers.
I use constant-voltage subtraction crossovers, but without any phase
compensation they do force one of the outputs to only roll off at 6db
per octave.
--
Chris Morriss
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