Nord Modular E-Tribe A User Guide

 

Description

This patch is a concise simulation of the bass synthesizer that is currently marketed by Korg known as the Electribe EA-1. This patch provides one-half of what Korg packages together in the product.

The E-Tribe A is a simple two oscillator synthesizer designed to produce a wide range of harmonically interesting lead and bass sounds. The basic patch is configured to be used monophonically. However, given its relatively low usage of DSP resources it can also be used effectively as a polyphonic instrument.

Feature-wise the synthesizer consists of two oscillators each with a variety of waveforms. These then drive a low pass filter with adjustable sharpness of 12, 18, or 24db. The signal path then feeds the standard envelope controlled amplifier. A final stage of effects processing provides adjustable distortion and two effect sends to drive an external delay and reverb unit as a way of example.

Portamento is provided and is triggered through legato play. Adjustments are available for determining the effect that velocity has on both amplitude and filter dynamics.

Two envelope generators are provided, which is more then the standard Korg unit. The first is a simple attack-decay/release (two time constants) which is used to drive the filter cutoff frequency as well as providing optional pulse width modulation of oscillator 1. A second is a full ADSR envelope for volume control but, aside from its release setting, is basically hidden unless the user decides to program sounds using the Nord Modular's edit features.

Various interactions between the two oscillators create rich harmonic starting material beyond the normal waveforms. Both oscillators offer switchable waveforms SAW, SINE, TRIANGLE, and PULSE. OSC2 PULSE is fixed at 50% duty cycle while OSC1 has an adjustment for pulse width as well as pulse width modulation. The output of each oscillator drives a balance control that lets the user selected the amount of each oscillator that feeds the filter.

The two oscillators are both driven by the same frequency control so they will track notes played. OSC2 features both an offset control and a fine control that lets the two oscillators be detuned. The offset control lets the oscillators be set to fixed intervals and also plays an important role when combined with the cross modulation capabilities.

Three cross modulations can be selected. The first is SYNC where OSC2 is hard sync'ed to OSC1. By altering the frequency interval between the two classic sync waveforms can be achieved.

The second is ring modulation. OSC1 modulates OSC2 amplitude and creates resulting AM spectrum. The modulation is not balanced by design so the center frequency component of OSC2 will be present. This can be adjusted if desired within the patch through the editor but has the side effect of making OSC2 inaudible when it is not in the AM mode.

The final is linear FM of OSC2 by OSC1. A modulation depth control allows setting of the modulation index.

 

Plus Version

I have a standard way of providing remote control and editing of all my Nord patches and have applied the same to the Electribe-A in the "Plus" version patch. These features consume a little bit of DSP and some module count but add some useful features.

The biggest addition is that the critical timbre parameters all now have relative adjustments. This feature is heavily used in Yamaha gear is useful for modifying a patch in a simple and predictable manner. The standard that I follow (see MIDI Chart) defines eight parameters all of which have no effect when set to the value of 64. Above 64 there is an increase in that parameter over the default patched value, below 64 it is decreased. Parameters included with relative adjustments are: Attack, Decay, Release (for the hidden AMP Envelope); Decay for the Filter envelope; filter envelope amount; filter cutoff and resonance; and an overall "timbre variation" adjustment that is wired through a morph controller to allow you to set the degree and nature of varying the timbre.

The Plus version still manages to come in under 50% DSP which was the goal for this emulation so that two voices could be done with one Micromodular or one slot of the full Modular.

 

Description of Parameters (front panel controls shown in parentheses)

These are arranged in module order from top to bottom, left to right. Parameters in Italics are not generally intended for user adjustment.

DYNAMICS

Vel. Sen. - determines how Expression control affects volume. In the off position (full counter clockwise) Expression has no effect and volume is not attenuated. Full clockwise and Expression has full effect. Use this setting to allow some degree of control over dynamics with Expression but not enough so that Express can turn it full off.

All other module parameters should not be adjusted

 

FILTER ACCENT

Vel. Sen. - determines how Velocity control affects filter envelope amount. In the off position (full counter clockwise) Velocity has no effect and the EG affects the filter normally. Full clockwise and Velocity has full effect, causing the amplitude of the filter EG depth to track Velocity exactly. This setting can be used to determine how much accented notes affect filter cutoff.

L. Gain - Sets Velocity curve below keyboard breakpoint

Brk. Pt. - Which note defines upper and lower.

R. Gain - Sets Velocity curve above keyboard breakpoint

AMP ACCENT

Vel. Sen. - determines how Velocity control affects AMP envelope amount. In the off position (full counter clockwise) Velocity has no effect and the AMP envelope operates normally. Full clockwise and Velocity has full effect, causing the amplitude of the AMP envelope depth to track Velocity exactly. This setting can be used to determine how much accented notes affect volume.

L. Gain - Sets Velocity curve below keyboard breakpoint

Brk. Pt. - Which note defines upper and lower.

R. Gain - Sets Velocity curve above keyboard breakpoint

 

EXPRESSION

Level - MIDI controlled Expression input

 

MORPH

Morph1 (Timbre Adjust). - morphing control using Defined Timbre relative adjustment

Morph2 (ModWheel). - morphing control using ModWheel. Intended for controlling "motion" aspects of a patch

Morph3 (FootController). - morphing control using Foot Controller. Intended for controlling timbral character of patch

Morph4 (AfterTouch). - morphing control using After Touch. Used to control effects aspects of patch

TUNE

Level - Pitch offset in semitones

PORTAMENTO (GLIDE)

Level - Portamento rate

ACCENT

Fade - This is a bipolar control. In the middle setting (MIDI Value = 64) the velocity received affects the patch, as determined by Filter Accent and AMP Accent and Filter Cutoff Accent, with maximum dynamic range. Increasing the value diminishes the dynamic range while gradually moving the mid-value up towards full velocity. Lowering the value also diminishes the dynamic range until at a value of zero there is no velocity effect and the effective velocity sent for further processing is mid-value (64).

OSC1

Coarse Frequency - determines the tuning of both OSC1 and OSC2

Fine Frequency - sets fine frequency for both OSC1 and OSC2

KBT - should be off as pitch from keyboard is routed through Glide.

Wave Select (OSC1 WAVE) - OFF, SINE, TRIANGLE, SAW, PULSE

Pitch MA1 - should be full on as this is the pitch control from the glide circuit. Adjust to less then full if normal key-tracking is not desired.

Pitch MA2 - should be full on as this is the input from the instrument TUNE control.

PWM - should be full on as it is driven by external pulse width controls.

 

Pulse Width (OSC1 PW)

Level - determines starting pulse width of OSC1 PULSE output

PWM

Lin - Should not be adjusted

Inv1 - Should not be adjusted

Mix1 - Amount of EG applied to modulate pulse width of OSC1

Inv2 - Should not be adjusted

Mix2 - Should not be adjusted

OSC2

Detune (OSC2 PITCH OFFSET) - Coarse adjust of ration between OSC1 and OSC2 frequency

Fine (DETUNE) - fine adjustment of frequency ratio between OSC1 and OSC2

Wave Select (OSC2 WAVE) - OFF, SINE, TRIANGLE, SAW, PULSE

FMA (FM DEPTH) - FM depth control

 

OSC BALANCE

Balance MA - How much balance modulation from EG

Balance (OSC BAL) - OSC1 to OSC2 mix. Full counterclockwise is OSC1 only, Full clockwise is OSC2 only

 

OSC MOD

Switch1 (SYN) - Enable OSC2 to be synced by OSC1

Switch2(AM) - Enable OSC2 to be amplitude modulated by OSC1

Switch3(FM) - Enable OSC2 to be frequency modulated by OSC1

Switch4(OFF) - No modulation

FILTER

Frequency (CUTOFF) - filter cutoff frequency

Res (RES) - Filter resonance

KBT - filter keyboard tracking. Normally off.

Type Select - OFF, LP, BP, HP, BR

db/oct - 12db/OCT, 24db/OCT

Freq MA1 - envelope depth scaling controlled via MIDI.

Freq MA2 - should be full on as this is the input from velocity depth

EG DEPTH

Lin - Should not be adjusted

Inv1 - Should not be adjusted

Mix1 - Amount of EG applied to filter. 12 O'clock position is off. Full counterclockwise is full negative modulation, full clockwise is full positive modulation

Inv2 - Should not be adjusted

Mix2 - Should not be adjusted

 

EG

Attack - EG Attack Rate

Hold - EG Hold Time (normally 0.5msec)

Decay - EG Decay Rate

Decay Mod - EG Decay Rate relative adjust input

AMP EG

Attack - AMP EG Attack Rate

Decay - AMP EG Decay Rate

Sustain - AMP EG Sustain Level

Release - AMP EG Release Rate

Attack Mod - AMP EG Attack Rate relative adjust input

Decay Mod - AMP EG Decay Rate relative adjust input

Sustain Mod - AMP EG Sustain Level force on via MIDI (Gate Mode)

Release Mod - AMP EG Release Rate relative adjust input

 

DISTORTION

Overdrive MA - Amount of modulation provided by EG for distortion

Overdrive - Amount of distortion

 

VOLUME

Lin - Should not be adjusted

Inv1 - Should not be adjusted

Mix1 (Volume) - Volume adjustment.

Inv2 - Should not be adjusted

Mix2 - Should not be adjusted

 

REVERB

Level - FX Send level to OUT4

 

DELAY

Level - FX Send level to OUT3

 

PAN

Pan - Left-Right Adjust

 

OUT

Level - Dry output level adjust - not normally adjusted

 

FRONT PANEL TEMPLATE

 

 

MIDI CONTROL CHANGE ASSIGNMENTS

CC

MIDI SPEC

Studio STD

E-Tribe A

0

Bank MSB

Bank MSB

 

1

Modulation

Modulation

Modulation controlled morph

2

Breath

Assignable 1

 

3

 

Assignable 2

 

4

Foot

Character

Foot controlled morph

5

Portamento

Portamento

Portamento

6

Data Entry

Data Entry

 

7

Volume

Volume

Volume

8

Balance

Main OSC Mix

OSC Balance

9

 

OSC2 Mix

 

10

Pan

Pan

Pan

11

Expression

Expression

Expression

12

Effect Control 1

Effect Control 1

DISTORTION

13

Effect Control 2

Effect Control 2

 

14

 

Dynamics

 

15

 

Filter Overdrive

 

16

GP Control 1

Filter Cutoff

CUTOFF

17

GP Control 2

Filter Q

RESONANCE

18

GP Control 3

Primary (AMP) EG Attack

AMP EG ATTACK

19

GP Control 4

Primary (AMP) EG Decay

AMP EG DECAY

20

 

Primary (AMP) EG Sustain

AMP EG SUSTAIN

21

 

Primary (AMP) EG Release

AMP EG RELEASE

22

 

AMP Gate/EG Switch

FORCE AMP SUSTAIN = FULL

23

 

Filter EG Depth

FILTER EG DEPTH

24

 

Filter Velocity Depth

FILTER EG VELOCITY DEPTH

25

 

Accent

ACCENT

26

 

LFO Depth

 

27

 

LFO Wave

 

28

 

LFO Rate

 

29

 

Aux LFO Modulation Depth

 

30

 

Filter LFO Modulation Depth

 

31

 

AMP LFO Modulation Depth

 

32

Bank LSB

Bank LSB

 

33

 

AMP Velocity Depth

AMP VELOCITY SENSITIVITY

34

 

Timbre Velocity Depth

FILTER CUTOFF VELOCITY DEPTH

35

 

Filter Key Track

 

36

 

LFO2 Wave

 

37

 

LFO2 Rate

 

38

 

Timbre LFO Modulation Depth

 

39

 

LFO2 Delay

 

40

 

LFO3 Wave

 

41

 

LFO3 Rate

 

42

 

Pitch LFO Modulation Depth

 

43

 

LFO3 Delay

 

44

 

Timbre EG Attack

 

45

 

Timbre EG Decay

 

46

 

Timbre EG Sustain

 

47

 

Timbre EG Release

 

48

 

Alt Timbre EG Depth

 

49

 

Filter EG Attack

FILTER EG ATTACK

50

 

Filter EG Decay

FILTER EG DECAY

51

 

Filter EG Sustain

 

52

 

Filter EG Release

 

53

 

Pitch EG Attack

 

54

 

Pitch EG Decay

 

55

 

Pitch EG Depth

 

56

 

Timbre EG Depth

PWM FILTER EG DEPTH

57

 

Main OSC Waveform

OSC1 WAVE

58

 

Main OSC Tune

OSC1 TUNE

59

 

OSC2 Waveform

OSC2 WAVE

60

 

OSC2 Interval

OSC2 OFFSET

61

 

OSC2 Detune

DETUNE

62

 

Pitch EG Sustain

 

63

 

Pitch EG Release

 

64

Sustain SW

Sustain SW

Sustain SW

65

Portamento SW

Portamento SW

 

66

Sostenuto SW

 

 

67

Soft SW

 

 

68

Legato SW

 

 

69

Hold 2

 

 

70

Sound Variation

Timbre

OSC MODULATION

71

Timbre

Presence

FILTER RESONANCE ADJUST

72

Release

Release

AMP EG RELEASE ADJUST

73

Attack

Attack

AMP EG ATTACK ADJUST

74

Brightness

Tone

FILTER CUTOFF ADJUST

75

Decay

Decay

AMP EG DECAY ADJUST

76

Sound CTL 7

Timbre Rate

FILTER EG DECAY ADJUST

77

Sound CTL 8

Timbre Mod

FILTER EG DEPTH ADJUST

78

Sound CTL 9

<reserved>

 

79

Sound CTL 10

<reserved>

 

80

GP Control 5

Variation

OSC MODULATION SELECT

81

GP Control 6

Timbre Control 1

PULSE WIDTH

82

GP Control 7

Timbre Control 2

FM DEPTH

83

GP Control 8

Timbre Control 3

DISTORTION EG DEPTH

84

PortamentoCTL

 

 

85

 

Tune

TUNE (SHIFT PITCH)

86

 

Low EQ Gain

 

87

 

Low EQ Frequency

 

88

 

High EQ Gain

 

89

 

High EQ Frequency

 

90

 

Filter Type

FILTER TYPE

91

FX1 Depth

FX1 Depth

REVERB SEND

92

FX2 Depth

FX2 Depth

 

93

FX3 Depth

FX3 Depth

 

94

FX4 Depth

FX4 Depth

DELAY SEND

95

FX5 Depth

FX5 Depth

 

96

Data Entry +1

Data Entry +1

 

97

Data Entry -1

Data Entry -1

 

98

NRPN LSB

NRPN LSB

 

99

NRPN MSB

NRPN MSB

 

100

RPN LSB

RPN LSB

 

101

RPN MSB

RPN MSB

 

102

 

 

 

103

 

 

 

104

 

 

 

105

 

 

 

106

 

Mix Low EQ Gain

 

107

 

Mix Low EQ Frequency

 

108

 

Mix High EQ Gain

 

109

 

Mix High EQ Frequency

 

110

 

Mix Parametric EQ Gain

 

111

 

Mix Parametric EQ Frequency

 

112

 

OSC3 Waveform

 

113

 

OSC3 Interval

 

114

 

OSC3 Detune

 

115

 

OSC3 Mix

 

116

 

 

 

117

 

 

 

118

 

 

 

119

 

 

 

120

All Sound Off

All Sound Off

All Sound Off

121

Reset All CTL

Reset All CTL

Reset All CTL

122

Local SW

Local SW

Local SW

123

All Notes Off

All Notes Off

 

124

Omni Off

Omni Off

 

125

Omni On

Omni On

 

126

Poly

Poly