HFD (DLCP) filter design optimization?

[TNT]

So how is a 6dB/oct passband slope made the best way? The passband is narrow, say only 1,5 octave (300-800Hz). This is for compensating for the lack of a baffle.

There are a few ways to do this with the filter arsenal of HFD:

- 1st order LP (LPF1)
- positioning the right part of a shelf filter in the right position (Shelf2)
- asymmetric shelf
- boost/cut

But which design would do the best job? And what can be considered best?

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