Oberheim OB 12, Руководство по эксплуатации

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OB 12 Z-Domain Synthesizer
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An ADSR envelope is therefore subdivided into:
- ATTACK
Time: the time which passes from when a key is pressed to when the maximum level
is reached.
-
DECAY Time: the time taken to pass from the maximum level to the SUSTAIN level:
- SUSTAIN Level: the level at which the signal remains as long as the key is kept pressed.
-
RELEASE Time: time the level takes to return to zero once the key has been released.
In this example we have been talking about “level”: as we will see, when we are dealing with the
filter, this is really the operating frequency of the filter. The envelope which controls a signal level
is applied to the amplifier (see point 8.5).
But now we will move on to the Filters section programming pages.
From the EDIT TIMBRE MENU, select field 5-FILTER and the display will show:
containing the following programming parameters:
•
FILTER1
([FILTER 1])
: sets the type of the first filter by means of the values LOW PASS, BAND
PASS, HIGH PASS and FLAT, already described.
•
F.1 FREQ.
(Filter 1 Frequency, [FREQUENCY])
: regulates the cut-off frequency of the first filter, in
correspondence with the point of origin of the envelope.
•
FILTER2
([FILTER 2])
: sets the type of the second filter by means of the values LOW PASS,
BAND PASS, HIGH PASS and FLAT, already described.
•
F.2 DELTA
(Filter 2 Ratio)
: sets the variation (Delta), in semitones, of the cut-off frequency of the
second filter compared to that of the first filter. The values cover a range from –96 (eight
octaves below F.1 Freq.) to +24 (two octaves above F.1 Freq.).
•
RESONANCE
([RESONANCE])
: sets the resonance coefficient of the filter, which can be used
to emphasise (enhance) the harmonics present in the cut-off frequency area, to create a
more distinct sound. The values which can be assigned to this parameter range from 0 (no
resonance) to 100 (maximum resonance). Look at this graphics on par. 7.4 for a clearer
understanding of the resonance effect.
Now select the DEPTH folder and the display will show: