User manual R3
DLCP
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4.8
Filter example
Example design using an existing M-T-M two-way cabinet.
4.8.1
The substrate
The pre-existing cabinet used here is not an example of good acoustic design. A 1” dome tweeter is
placed between two 5¼” woofers in perfect lateral and vertical symmetry. The measured responses
are as wild as would be expected:
Figure 24
The first reflection arrives after 8ms so this plot conveys no meaningful information about the re-
sponse below 200Hz. Not shown is a separate close-up measurement of the woofers to determine
the precise low-frequency response.
4.8.2
The filters
The following series of biquads is used to filter and correct the drivers:
The corrections were hand-optimised because an automatic optimisation algorithm can’t be ex-
pected to judge which corrections make physical sense and which don’t.
