Operation Manual

DR. REX LOOP PLAYER
190
Dr.Rex Synth Parameters
The Dr.Rex synth parameters are used for shaping and modulating the sound of the
REX loops. These parameters are familiar synth parameters, similar to the ones in the
synthesizers; The Subtractor and the Malström, and in the samplers; the NN-19 and
the NN-XT. It is important to remember that these parameters do not alter the REX
files in any way, only the way they will play back.
! These parameters are global, in the sense that they will affect all slices in
a REX file.
Oscillator Section
For a REX file, the audio contained in the slices are what oscillators are for a synthe-
sizer, the main sound source. The following settings can be made in the Osc section
of the Dr.Rex:
Setting the overall Pitch
You can change the pitch of a REX file in three ways:
D In octave steps.
This is done using the Oct knob. The range is 0 - 8, with “4” the default.
D In semitone steps.
This is done by using the Transpose knob below the waveform display, or by click-
ing on the keyboard above the knob. You can raise or lower the frequency in 12
semitone steps (+/– 1 octave). The transpose value can also be changed via MIDI,
by pressing a key between C-2 and C0 (with C1 resetting the transpose value to
zero).
D In cents (hundredths of a semitone).
The range is -50 to 50 (down or up half a semitone).
! To tune an individual slice, you select it and use the Pitch parameter be-
low the waveform display.
Osc Envelope Amount
This parameter determines to what degree the overall pitch of the REX file will be af-
fected by the Filter Envelope (see page 191). You can set negative or positive values
here, which determines whether the envelope curve should raise or lower the pitch.
The Filter Section
Filters are used for shaping the overall timbre of the sound. The filter in Dr.Rex is a
multimode filter with five filter modes.
D You activate or deactivate the filter completely by clicking the Filter but-
ton.
The filter is active when the button is lit.
Filter Mode
With this selector you can set the filter to operate as one of five different types of filter.
These are as follows:
D 24 dB Lowpass (LP 24)
Lowpass filters lets low frequencies pass and cuts out the high frequencies. This
filter type has a fairly steep roll-off curve (24dB/Octave). Many classic synthesizers
(Minimoog/Prophet 5 etc.) used this filter type.
D 12 dB Lowpass (LP 12)
This type of lowpass filter is also widely used in classic analog synthesizers (Ober-
heim, early Korg synths, etc.). It has a gentler slope (12 dB/Octave), leaving more
of the harmonics in the filtered sound compared to the LP 24 filter.
D Bandpass (BP 12)
A bandpass filter cuts both high and low frequencies, while midrange frequencies
are not affected. Each slope in this filter type has a 12 dB/Octave roll-off.
D High-Pass (HP12)
A highpass filter is the opposite of a lowpass filter, cutting out lower frequencies
and letting high frequencies pass. The HP filter slope has a 12 dB/Octave roll-off.
D Notch
A notch filter (or band reject filter) could be described as the opposite of a band-
pass filter. It cuts off frequencies in a narrow midrange band, letting the frequen-
cies below and above through.
Filter Frequency
The Filter Frequency parameter (often referred to as “cutoff”) determines which area
of the frequency spectrum the filter will operate in. For a lowpass filter, the frequency
parameter could be described as governing the “opening” and “closing” of the filter. If
the Filter Freq is set to zero, none or only the very lowest frequencies are heard, if set
to maximum, all frequencies in the waveform are heard. Gradually changing the Filter
Frequency produces the classic synthesizer filter “sweep” sound.