16
Track One
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 bandwidth
increases (the exact curves of the MHF filter can be seen in diagram 3 on page 21). The filter
construction permits the complete scope, from selective removal of accentuated frequen-
cies 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.
AIR BAND
The high frequency filter in the equalizer module is described as the AIR BAND. A coil-
capacitor-filter with so called bell characteristics and a center frequency of 17.5 kHz comes
into operation here. At this frequency the maximum possible accentuation is +10 dB, the
maximum possible damping is -10 dB.
The soft and natural tonal property, characteristic of the coil-capacitor filter, lends itself
extremely well to provide clarity and ... well, air, to vocals in the upper frequency range
thereby improving their presence. On the other hand harsh sounds can be lent a more pleasant
sound characteristic through damping.
The characteristics of the AIR BAND filter are shown in diagram 4 on page 21
.
OUTPUT GAIN
The outgoing signal can either be dampened to -20 dB or further amplified by +5.5 dB with the
OUTPUT control to provide optimal drive to the subsequent units or the optional AD converter.
The selected output level is shown on the PPM OUTPUT display in the display field.
Before a recording commences the OUTPUT control should be set to 0 dB (12 o’clock position):
the uninfluenced values are then legible and available for adjustment of the preamplifiers
levels. (see
„Gain adjustments“ on page 11).
Control Elements
Control Elements
Equalizer
Output Gain
