Heckmann Audio Repro-1 100B, Operation Manual

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2-2 OSCILLATOR A
FREQUENCY knob: Adjusts pitch within a two-octave range (+/– 12 semitones).
FINE TUNING trimmer between FREQUENCY and OCTAVE: Adjusts pitch within a 40
cent range (+/– 20 cents). Its main purpose is to adjust the rate of beating between
the two oscillators when they are tuned almost in unison.
OCTAVE rotary switch: Transposes oscillator pitch over a four-octave range.
SAWTOOTH SHAPE switch: The UP position activates the standard brassy waveform
containing all harmonics (odd as well as even).
PULSE SHAPE switch: The ‘up’ position enables a waveform with a harmonic content
that depends on the PULSE WIDTH setting but sounds generally more hollow than the
sawtooth. If neither SHAPE is switched on, OSCILLATOR A is silent. If both SHAPEs
are active, the mixture normally has a lower volume than each single shape due to the
phase relationship between the saw and pulse. To remedy this effect, set the P5 option
(see Oscillator Tweaks on page 31).
PULSE WIDTH knob: Adjusts the harmonic content of the pulse wave by setting its
“duty cycle”. The range is from 0% to 100%. Double-click on the knob for a 50% pulse
(a clean square wave which only contains odd-integer harmonics).
Notes: At extreme values, the signal gets so thin that it becomes inaudible (DC, direct
current). The PULSE WIDTH knob has no effect on the sawtooth.
SYNC switch: Hard synchronization forces the waveform of OSC A to reset whenever
OSC B hits zero. The frequency of OSC A generally needs to be higher than OSC B for
this to work properly. Experiment: Intermediate FREQUENCY values can produce
unusual timbres at the next lower harmonic of OSC B.
INTRO SYNTH SEQUENCER KEYS-PERF EFFECTS TWEAKS CONFIG NKS
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