LMF
The center frequency of the half-parametric bass filter is set with the LMF control (low/mid
frequencies).
The adjustable frequency range lies between 30 Hz and 700 Hz so that this filter covers a
range of about 4.5 octaves, allowing it to be used from the deepest bass to the lower mid
range.
This together with the MHF filter ensures that the entire frequency spectrum is covered.
LMF -/+
The LMF-/+ control determines the boost or cut of the LMF filter; the maximum values lie
between +/- 14 dB. The LMF filter also operates to the proportional-Q-principle, in other
words the bandwidth is dependent on the selected boost or cut. This filter characteristic
permits a musically more sensible processing of the frequency spectrum than with constant-
Q filters: if a more thorough setting has been chosen this will lead to far preciser definition
of the frequency range to be processed. This in turn minimizes influences from adjacent
ranges.
The boost or cut values, in relation to the bandwidth, lie somewhat higher than with the MHF
filter. The bandwidth is therefore narrower at maximum boost than with the MHF filter for
even more precise filtering. The exact curve of the LMF filter is shown in diagram 4 on page
27.
The LMF filter can be applied in many ways. Examples are; to accentuate the fundamental
sound of a voice, to cut “boom” frequencies and for placement of bass emphasized instru-
ments during recording or subsequently when mixing etc.
MHF
The center frequency of the semi-parametric mid/high frequency filter is set with the MHF
control.
The frequency range can be set between 680 Hz and 15 kHz so that this filter covers a range of
4.5 octaves and can be equally employed in the lower mid as well as the high range.
This together with the LMF filter ensures that the entire frequency spectrum is covered.
MHF -/+
This control determines the boost, or cut of the MHF filter; the maximum values lie between
+/- 12 dB. The MHF filter utilizes the proportional-Q-principle, too: the higher the boost or cut
values are set, so the bandwidth becomes narrower; by low boost or cut values the band-
width increases (the exact curves of the MHF filter can be seen in diagram 3 on page 27).
The filter construction permits the complete scope, from selective removal of accentuated
frequencies through to character giving accentuations of an instrument, to be effectively and
quickly covered.
Recommendation on frequency settings for LMF and MHF
To find the frequency which is to be processed as quickly and accurately as possible, firstly
adjust the MHF -/+ control to the maximum position. Subsequently the relevant frequency
should be sought. Because the filter at maximum setting works with the smallest bandwidth,
the frequencies can be heard most distinctly at this setting, making them easier to locate.
Finally the desired MHF +/- setting can be applied after the frequency is determined with
MHF.
18
Channel One
Equalizer
Control Elements
