Orthogonal Devices ER-102 User manual

User Manual
ER-102:
Sequencer Controller
with Firmware v1.04
Last revised on April 4, 2015
OD
Orthogonal Devices © 2015
IntroductIon 3
What does it do? 3
The interface 3
Math transforMs 4
Edit screen 4
Operations 5
Identity 5
Inversion 5
Examples 6
Parts 7
What are parts? 7
Interface 8
Voltage control 9
Various types of parts 10
Transitions 11
GrouPs 12
What are groups? 12
Selecting steps 12
Applying transforms 13
Modiers 14
recordInG 16
Real-time mode 17
Step mode 19
Alter mode 20
rotoInversIon 21
storaGe 22
Snapshots 23
Loading MIDI Files 24
User Voltage Tables 25
The Conguration File 26
Updating the rmware 27

2
Please update your ER-101 to at least v2.02 of the
rmware before connecting it to the ER-101.

3
What does it do?
The ER-102 Sequencer Controller is an expander for the ER-101. The design and
feature set implemented by the ER-102 is the result of the critical distillation of the
many overlapping feature requests that were made by users during the rst year of
the ER-101’s release.
TIP: Throughout this manual, I will assume that you are already familiar with the ER-
101’s interface. If that is not the case then please rst read the ER-101 User Manual.
The interface
The ER-102 interface is divided into 4 sections:
• STORAGE: a memory card for holding snapshots and loading rmware.
• PARTS: adds up to 99 CV-controllable loops (each with their own reset step) to
each snapshot.
• GROUP: adds up to 16 arbitrary selections of steps each with their own trans-
forms and routing matrix that is connected to a 3 channel modulation bus.
• RECORDING: adds a comprehensive and recongurable set of inputs that can
record new sequences, alter existing ones, or place the ER-101 under remote
editing control.
The ER-102 was designed to be place to the right of the ER-101. This layout was
chosen to minimize the impact on your hand motions when including the ER-102
in your workow. For example, the LEFT knob on the ER-101 is used whenever
changing any values on displays with focus buttons on their right (INDEX, TRACK,
PATTERN, STEP, SNAPSHOT, PART and GROUP). The RIGHT knob on the ER-101 is
used whenever changing any values on displays with focus buttons on their left
(VOLTAGE, vCV-A, CV-B, DURATION, and GATE). The result is that your hands never
obstruct the displays that you need to see while you are manipulating the interface.
TIP: Throughout this manual, a “focus press”means to press the focus button of a
display that is already focused. If the display is not focused, then you will need to
focus it rst and then press it again to get the desired eect.
IntroductIon
The possible targets for the LEFT knob are highlighted.
The possible targets for the RIGHT knob are highlighted.

4
Under the ER-101/102 paradigm, whenever you want to operate mathematically on
the parameters of a single step or multiple steps, you use a MATH transform. Exam-
ples of such operations are transposing pitch values, randomizing gate lengths, dou-
bling or halving step durations, and quantizing random note durations or pitches to
a xed grid.
There are two types of transforms, destructive and non-destructive. A destructive
transform permanently alters the stored parameters of the target steps. These
destructive transforms are always accessed via the MATH button. A non-destructive
transform alters step parameters as they are being interpreted during playback but
without changing their stored values. You will nd non-destructive transforms in
the GROUP MODIFIER section of the ER-102’s interface.
All transforms share the following interface:
UI Element Function
LEFT knob Selects an operation (i.e. add, multiply, randomize, etc.).
RIGHT knob Changes the focused operator’s parameter.
FOCUS buttons Focuses the interface on a particular step parameter.
DELETE button Clears all operations so that the transform has no eect.
Edit screen
Pressing and holding the MATH button will activate the TRANSFORM EDIT screen for
any of the desctructive transforms associated with tracks and groups.
TIP: When you rst enter the TRANSFORM EDIT screen, the word “PIN” will be ash-
ing in the VOLTAGE display. Press the VOLTAGE focus button to pin the TRANSFORM
EDIT screen so that you do not have to hold the MATH button while making long
edits to the transform. Pressing the MATH button while pinned in the edit screen
will apply the current MATH transform.
The TRANSFORM EDIT screen for the non-destructive group transforms is automati-
cally activated when editing the GROUP MODIFIERS (refer to the chapter on groups).
Math transforMs
The TRANSFORM EDIT screen: Turning the LEFT knob will change the focused
operation for the focused parameter (in this case CV-A). Turning the RIGHT knob will
change the focused operation’s paramter value.

5
Operations
Whenever you apply a transform, all of the operations that it contains are applied
sequentially in the following order to each step parameter:
1. Add RANDOM(Rd)
2. Multiply by G
3. Add JITTER(Jt)
4. Add A
5. Quantize to Qt
The result is the following formula:
Pafter= QUANTIZE(G*(Pbefore+ RANDOM(Rd)) + JITTER(Jt) + A,Qt)
where,
Pafter: The new value of the step parameter
Pbefore: The old value of the step paramter
QUANTIZE(x,y): Round x to the nearest multiple of y
RANDOM(x): Random integer between 0 and x (uniform distribution)
JITTER(x): Random integer between -x and x (uniform distribution)
If for a particular step and parameter, the transform results in a Pafter that is outside
the valid range of the step parameter then the transform will have no eect on that
parameter. For example, trying to subtracting 50 from CV-A = 12 will have no eect.
TIP: In the case of non-destructive transforms, the Jitter and Random operations are
re-evaluated every time a target step is played.
Identity
A transform with all default values for each of its operations has no eect and is
called the identity transform. You can quickly reset any transform back to its identity
by pressing the DELETE button while in the TRANSFORM EDIT screen.
Inversion
You can invert a transform that you are editing by pressing the INVERT button. Also,
you can apply the inverted version of a transform by holding the INVERT button
while pressing and releasing the MATH button. Transform inversion only applies to
the Add (A) and Multiply (G) operators.
Add 12.
Subtract 12.
Multiply by 2.
Divide by 2.
Add a random number
between 0 and 10.
Add a random number
between -3 and 3.
Round to the nearest
multiple of 8.
Code Operation Range Eect
A Addition -99 to 99 add A
G Multiplication 1/99 to 99 multipy by G
Jt Jitter 0 to 99 add a random integer between [-Jt, Jt]
Rd Random 0 to 99 add a random integer between [0, Rd]
Qt Quantize 1 to 99 round to the nearest multiple of Qt
The letter codes (aka variables) used in the TRANSFORM EDIT screen to represent
each operation.
Congurable Option: You can edit the conguration le to have only a single opera-
tion active at a time instead of all operations.

6
Examples
Set parameters to a specic value:
To achieve the aect of an assignment operation, just set G = 0 and set A to the
desired value. Typically you would do this when you want to simultaneously set a
particular parameter of many steps to a desired value (e.g. set the DURATION of all
steps in a pattern to 16 clock pulses). Additionally, you can use the JITTER(Jt) param-
eter to add a bit of zero-centered random noise to the parameter. This is especially
useful for velocity CVs and gate lengths.
Generate random parameter values in a given range:
The RANDOM operation produces random integers between 0 and Rd. If you want
random numbers between L and H, then just set A = L and Rd = H-L. For example,
to get random values between 12 and 19, set A = 12 and Rd = 7. This is often done
when producing random pitch values that are within a restricted range.
Generate random pitches separated by a given xed interval:
To generate random multiples of a given number just set Rd and A as you would for
producing random numbers in a range but also set G to the desired interval size. For
example, to produce random pitch values from one octave of the whole tone series
then set G=2, Rd=6, and set A to the root pitch. Alternatively, you can use RANDOM
with the QUANTIZE operation: Rd=12 and Qt=2.
Generate random rhythms with customized probabilities:
Start with a simple sequence of steps with all the GATE parameters set to zero. If
you apply a MATH transform of [GATE+RANDOM(4)]/3 to the entire track then you
will get random sample of steps with a GATE parameter of 1 and the rest will be zero.
Furthermore, if you start with a sequence of steps where some of the steps have a
GATE parameter of 1, 2 or 3 (rather than just zero) then these steps will have a pro-
gressively higher probability of being assigned a non-zero GATE after you apply the
MATH transform. This way you can sculpt the resulting random rhythm lightly by
biasing the randomization. For example, this is great for producing random rhythms
that have a higher probability of triggering on the strong beats then on the weak
beats.
This example works especially well with the HIGH/LOW transforms (see Groups)
because the initial probability contour is not overwritten by the application of these
non-destructive transform, and, the HIGH/LOW transforms get re-evaluated every-
time a step is played, thus producing a continually evolving rhythm that neverthe-
less adheres to the user’s specied probability contour.

7
What are parts?
The top section of the ER-102 is dedicated to the manipulation of parts. Using parts,
you can divide tracks into smaller sub-sequences (called parts) and then activate
these parts during playback using the manual interface or using voltage control. A
single snapshot can contain up to 99 parts.
Looping dierent sections of a track on just the ER-101 is a very eective way of
introducing variations in real-time. However, there are some limitations with a
standalone ER-101:
• You cannot save and recall multiple loops.
• You cannot activate dierent loops simultaneously across all or some tracks.
• You cannot change the step that the ER-101 rewinds to on a reset signal.
• There is no external voltage control of the play cursor.
The ER-102 removes each of these limitations by introducing the concept of a part.
A single part assigns a reset step and a looped section for each of the 4 tracks such
that when a part is triggered, potentially all tracks will have their reset steps and
looped sections changed.
Parts

8
Interface
At any time there will always be a part that is focused and a part that is play-
ing. Sometimes, there will also be part that is pending. When the PART display is
focused, you can change the part by turning the LEFT knob. Also, the INDEX and
VOLTAGE display are commandeered to show information relevant to the focused
part and the next pending part, if any.
Focused Part
The focused part is the part whose number is showing in the PART display. When
you are changing the reset step or the loop section for the current track, then your
changes are always applied to the focused part. The looped section of the focused
part is set with the LOOP START and LOOP END buttons on the ER-101, while the
reset step is assigned with the RESET TO button on the ER-102.
Pending Part
The pending part is the part that is scheduled to play next (i.e. after the current part
nishes). When the PART display is focused then the pending part will be shown in
the INDEX display on the ER-101. Also, the PART display’s orange LED will ash when
a part is pending.
Playing Part
The currently playing part is indicated by the dot in the lower right of the PART
display. All tracks will adhere to the reset step and looped section assigned in the
playing part.
Part Overview (experimental)
When the PART display is focused a rough overview of the focused part is shown
in the VOLTAGE display. The display is divided horizontally into 4 sections, one for
each track. Each section holds 3 horizontal bars that indicate (from top to bottom)
whether the RESET TO, LOOP START, and LOOP END steps have been set in their
respective tracks.
Quick Navigation
If you hold down the PART focus button and turn the LEFT knob then the cursor will
skip in order through the steps in the following list:
First step - RESET TO step - LOOP START step - LOOP END step - Last step
In this example, the PART display is focused and part 6 is showing. The VOLTAGE
display shows an overview of the part and we can see that track 1 has a RESET TO,
LOOP START and LOOP END all set, while track 2 only has the LOOP START and LOOP
STOP set. Track 3 has none of them set and track 4 has RESET TO and LOOP END set.
Additionally, we can see that part 3 is pending to be played after part 6.

9
Voltage control
Parts can be focused and activated using external voltage control just by patching
a suitable CV/gate source into the SELECT and ACTIVATE jacks on the ER-102. The
SELECT voltage is converted to a PART number according to the chart on the right.
TIP: As soon as you insert a cable into the SELECT jack, part selection is placed
under external voltage control. This means that the LEFT KNOB can no longer be
used to alter the focused part. If you try to change the focused part with the LEFT
knob while a cable is patched into the SELECT jack, the word“PLUG” will ash in the
VOLTAGE display to remind you that part selection is under external voltage control.
Remove the cable to once again be able to select parts via the LEFT KNOB.
Once a part is selected (or focused), then this part can be activated with gate signal
to the ACTIVATE jack. In fact, as long as the ACTIVATE input is held high the pending
part (or next part cued to play) will track the voltage selection. This allows you to
eectively “play” parts in real-time.
TIP: The actual timing of when the newly activated part starts playing depends on
the position of the TRANSITION switch (see the section on Transitions).
−10 −5 0 5 10
0 20 40 60 80 100
VOLTAGE
PA R T
part = oor(voltage*10)
maximum:99
minimum:0

10
Various types of parts
There is no restriction on how you assign the RESET TO, LOOP START and LOOP END
steps in a part. In the following, I will borrow terminology used to describe the
structure of popular songs because it is familiar and easy to understand. Suppose
the material for a song was laid out over a track or tracks in the following manner:
Intro-Verse-Chorus-Bridge-Outro
Material that is laid out this way is not meant to be played from start to nish but to
be sliced up and reordered.
Intro-[Verse-Chorus]
The most common kind of part assigns a RESET TO step to the beginning of a pas-
sage and then LOOP START and END to loop some portion of the latter half of the
passage. For example, in a ...ABCBCBC... song arrangement where A is the intro, B
is a verse and C is the chorus then you could easily arrange a part to play an intro
seamlessly segue into the refrain (i.e. repeating verse-chorus: BCBC...). See Part 1 in
the gure.
Chorus-[Verse-Chorus]
Sometimes you want to trigger a chorus and then return to the refrain. In this case
you would put the RESET TO step inside the looped section as in Part 4 of the gure.
Outro (or One-Shot)
If you want a section to play once and then play nothing afterwards then just set the
RESET TO step to the beginning of the section and then loop a single rest step (i.e.
step with GATE=0 or DURATION=0). See Part 3 in the gure.
The builtin STOP part
Finally, there is builtin part (always assigned to Part 0) that plays absolutely nothing
on all tracks when it is active. You can use this part to end all playing material.
Naked Loops
This is an important special case which is often used for bridges. See Part 5 in the
gure. When a part does not have a RESET TO step assigned then this part begins
playing from where the previous part left o. This means that the rhythmic relation-
ship (e.g. sync) of such“resetless”parts with other tracks can change depending on
what part is playing when they are triggered. On the other hand, parts with reset
steps will always start from the same place.

11
Transitions
Once a part is triggered, the exact time it will start playing depends on the setting of
the TRANSITION switch.
Triggering a part
Parts are activated or triggered in two ways - manually via the TRANSITION button
or remotely via a rising edge on the ACTIVATE input. As soon as the focused part is
activated then it also becomes the pending part and its number will be ashing in
the INDEX display when the PART display is also focused. When you trigger a part,
you are actually triggering parts across all of the tracks.
FIRST vs LAST Transitions
When transitioning from one part to the next, it is musically useful to wait for the
current part to nish playing before starting the next pending part. However, since
a single part potentially contains a loop for each track, there is an ambiguity about
when a part exactly nishes. In other words, which track gets to decide for the other
tracks that the current playing part has nished? The FIRST and LAST transition
modes solve this ambiguity. The FIRST transition mode means that the transition to
the pending part will occur as soon as any track completes its loop. In other words,
the rst track to complete its loop is used to nish the current part and transition to
the pending part. The LAST transition mode waits for all tracks to nish at least one
loop before moving on to the pending part. In other words, the last track to nish a
loop determines the transition to the pending part.
When the current playing part ends (as dened by the TRANSITION mode), then all
tracks with a RESET TO step dened are reset and the pending part becomes the
current playing part.
The USER Transition
The USER transition mode is by default congured to transition immediately without
a reset (even if there is a RESET TO step dened). However, a reset on the ER-101 will
behave as normal.
Congurable Option: The USER transition can have its behavior changed via the
conguration le. Please refer to the conguration le on your SD card for more
details.
In this example, parts have been dened for only 2 tracks and the TRANSITION
switch is set to FIRST. The dotted line indicates when the next part is triggered.
Track 1 nishes rst, so track 1 determines the beginning of the next part.
This is the same scenario as above except the TRANSITION switch is set to LAST.
Track 2 nishes last, therefore track 2 determines the beginning of the next part.

12
What are groups?
The middle section of the ER-102 is dedicated to groups. Groups are arbitrary selec-
tions of steps that can be the target of transforms and CV/gate modulation. Each
snapshot can contain up to 16 groups. There are 3 independent channels of CV/
gate moduation.
Selecting steps
Select by step (or pattern or track)
The most basic way to add steps to the current focused group, is to press the (DE)SE-
LECT button while the desired step is focused. Pressing the (DE)SELECT button adds
the step if it is not part of the group already, and removes the step if it is already part
of the group. The red selection LED (to the left of the GROUP display) will light up
when the focused step is in the focused group. Furthermore, the navigation focus
of the ER-101 (i.e. STEP vs PATTERN vs TRACK) is used to determine whether a single
step, or an entire pattern, or the entire track should be added (or removed) from the
group.
For example, to add all the steps of pattern #3 to group #1:
1. Navigate to group #1.
2. Navigate to any step in pattern #3 that is NOT a member of group #1.
3. Focus the PATTERN display.
4. Press the DE(SELECT) button.
And to remove all the steps of pattern #3 from group #1 just press the DE(SELECT)
button again. The selection state of the focused step determines whether the
whole pattern will be added or removed from the group. In other words, whatever
happens to the focused step will also happen to all the other steps in the focused
pattern. This same behavior applies to entire tracks when we have the TRACK dis-
play focused.
GrouPs

13
Copy a selection
If you press the COPY button while the GROUP display is focused then the current
group’s selection (but not the steps themselves) is copied to the clipboard. At this
point the GROUP display LED will start ashing. You can now navigate to another
group and paste the copied selection with the INSERT button. The pasted selection
will combine with the existing selection in the target group, creating the union of
the two selections.
Delete a selection
If you press the DELETE button while the GROUP display is focused then all steps are
removed from the focused group.
Rotate a selection
The ROTATE button will shift a group’s selection later in the sequence by one step.
So if step #4 and step #12 are selected then after pressing the ROTATE button, step
#5 and step #13 will be selected. Holding the INVERT button while pressing the
ROTATE button will shift the selection earlier by one step.
Invert a selection
Group membership can be inverted by focusing a group and pressing the INVERT
button. All steps that were in the group are taken out of the group and all steps that
were not in the group are placed in the group.
Applying transforms
Each group has its own destructive transform that is accessible via the MATH button
and also non-destructive transforms that are accessible as the high/low modiers.
Pressing the MATH button while the GROUP display is focused will show the de-
structive transform just like accessing the track transforms. When you apply a group
transform by pressing and releasing the MATH button, the transform will only alter
the parameters of those steps that are in the group.
You can edit the transform while holding down the MATH button and then apply
it by releasing the MATH button. Also, you can“pin”the transform edit screen by
pressing the VOLTAGE display button so that the screen stays when you release the
MATH button. In this case, press the VOLTAGE focus button (now displaying ‘dONE’)
again to exit from the transform edit screen. Apply the transform at any time by
pressing the MATH button. See the section on Math Transforms for a detailed de-
scription.

14
Modiers
The modiers of a group dictate how the 3 channels of CV/gate modulation (X, Y,
and Z) aect the steps within the group. The SLOPE modier holds the gain matrix
that routes the 3 CV inputs to each parameter of each step in a group. The HIGH and
LOW modiers are non-destructive transforms which are activated according to the
logic state of the 3 gate inputs (X, Y, and Z).
The Slope Matrix
This is one of those things that is actually very easy to understand when you are
using it but requires a lot of words to explain.
Each group has 3 slopes (X, Y, and Z) for each of the 4 step parameters (CV-A, CV-B,
DURATION, and GATE). The voltages present at each channel of the modulation bus
are multiplied by each group’s slope matrix and then added to each step parameter:
Pafter = Pbefore + KXVX+ KYVY+ KZVZ
where,
Pafter:step parameter after modication
Pbefore:step parameter before modication
KX, KY, KZ:The 3 slopes (or gains) associated with a given group
VX, VY, VZ:the voltages from the 3 modulation channels
In the case of CV-A and CV-B, this adjustment is added after the voltage table lookup
(i.e. after converting the CV index to an actual voltage). To access the slope parame-
ters for a particular modulation channel:
1. Toggle the GROUP MODIFIER HIGH/SLOPE/LOW switch to SLOPE.
1. Toggle the GROUP MODIFIER XYZ switch to the desired channel.
2. Press the GROUP MODIFIER focus button.
Now the GROUP display LED and the GROUP MODIFIER display LED will be lit. This
means that the LEFT knob on the ER-101 will alter the focused group and the RIGHT
knob will alter the slope value associated with the focused step parameter (i.e. CV-A,
CV-B, DURATION and GATE).
Congurable Option: You can congure the voltage that is used when there is no
jack plugged into the CV mod jacks. The default is zero volts.
X Y Z
CV-A 1.0 0.05 0.0
CV-B 0.0 0.25 0.0
DURATION 0.0 0.0 0.0
GATE -4.0 0.0 2.5
This table shows an example slope matrix that results in the following modications
to each step parameter:
CV-Aafter = CV-Abefore + 1.0VX + 0.05VY
CV-Bafter = CV-Bbefore + 0.25VY
DURATIONafter = DURATIONbefore
GATEafter = GATEbefore - 4.0VX + 2.5VZ
This is how the ER-101/102 appears when you are viewing/editing the Xcolumn
(1.0, 0.0, 0.0 -4.0) of the example slope matrix shown above. Notice the positions
of the GROUP MODIFIER switches. Since CV-A is focused, the value shown in the
VOLTAGE display is KXVX = (1.0)VXor just the voltage present at the CV input for
channel X.

15
When altering the slope, the size of the encoder increments depends on the slope’s
magnitude:
Min Max Increment
-99 -10 1
-9.9 -1.0 0.1
-0.99 0.99 0.01
1.0 9.9 0.1
10 99 1
This logarithmic scheme allows for ne control when dialing in small gains while
also making very large gains easy to reach.
High vs Low transforms
The GATE inputs on the 3 modulation channels (X, Y, and Z) control which of each
group’s (non-destructive) transforms are active. Each group has 6 of these trans-
forms because there are high and low transforms for each of the 3 channels which
comes out to 6 transforms per group. For example, a high voltage (>1.5V) on the
X channel GATE input will activate all of the X-high transforms, while a low voltage
(<1.5V) will activate all of the X-low transforms and so on.
TIP: If there is no plug in the GATE input jack then the low transforms are active by
default.
The usual interface for transforms is used to edit a group’s high/low transforms. See
the section on Math Transforms. However, there is no need to apply the high/low
transforms because they are applied automatically everytime a step plays.
The high/low transforms have many uses:
• Provide programmable osets for the CV modulation bus.
• Mute steps in a group by having the high transform multiply the GATE parame-
ter by zero.
• Skip steps in a group by having the high transform multiply the DURATION
parameter by zero.
• Momentarily double or half the step durations of a group for rhythmic eect.
This works especially well when you partition your sequence into two groups
each with opposite transforms (i.e. one group doubles in duration while the
other group halves the duration).
This example diagram shows the X channel’s HIGH transform for the steps in group
3. In this case, assuming the other operations are set to their default values, the
transform will decrease CV-A by an octave (subtract 12), leave CV-B untouched,
double the DURATION and divide the GATE length by 4.

16
The lower section of the ER-102 is dedicated to recording and remote control of the
ER-102 editing functions. In addition to the PUNCH IN/OUT gate input, there are 6
multi-purpose inputs:
A-1 and A-2: analog inputs that accept -10V to 10V
D-1 and D-2: digital inputs with a trigger threshold of 1.5V.
AD-1 and AD-2: can be used either as analog or digital inputs.
The role of each of these inputs depends on the record mode.
The ARM button and the PUNCH IN/OUT section are common to all of the recording
modes. Recording is enabled for one or more tracks by toggling the ARM button
while the desired track is focused. A track is armed when the ARM LED is lit. Assum-
ing the ER-101 is not paused, actual recording begins when you punch in via the
PUNCH IN/OUT button, or, via a high gate signal on the PUNCH IN/OUT gate input.
Recording stops again when you press the PUNCH IN/OUT button again, or, when
the PUNCH IN/OUT gate goes low. The ER-102 is actively recording when the REC
LED is lit.
recordInG

17
Real-time mode
The real-time recording mode is used to capture a live performance as a step
sequence. Timing of CV and gate changes are measured against the clock (af-
ter per-track multiplication) and then re-interpreted as a sequence of steps with
quantized voltages and timing. Real-time recording starts on all armed tracks when
the PUNCH LED is lit and the ER-101 is not paused. The newly recorded steps are
inserted at the current location of the play cursor. In fact, in real-time mode the
play cursor and the record cursor are the same. So if you want to see what you are
recording then put the ER-101 in FOLLOW mode.
The A-1 and A-2 analog inputs are routed to CV-A and CV-B, respectively. The AD-1
input is placed in digital mode and expects a gate signal that goes high for a “note
on”event and goes low for a“note o” event. In other words, the time between two
consecutive rising edges on this gate input determines the duration of the record-
ed step, while the time between a rising edge and a falling edge determines the
recorded step’s gate length.
Congurable Option: The unused D-1, D-2 and AD-2 inputs can be congured to
control other aspects while in this mode. See the conguration le on your SD card
for more details.
The CV index that is assigned to the current recording step is determined in the
following manner. Once a new step has started, the ER-102 then waits for approx-
imately half a clock pulse before sampling the A-1 and/or A-2 inputs. This helps
insure that the voltage on these inputs has settled to an accurate value. The value
that is sampled (with 14-bits of resolution) is truncated to the output range of the
ER-101 (0V to 8.192V) and then quantized to the nearest entry in the track’s voltage
table.
The re-interpretation of your performance as a step sequence means that glides,
vibrato, or any continuous CV movements will not retain their smooth nature. How-
ever, you can regain some of these smooth movements later by manually enabling
smoothing on the necessary steps. Vibrato-types of modulation are best added later
using the modulation bus of the GROUP section.
TIP: While recording, the live inputs (A-1, A-2 and AD-1) are passed unchanged
to the outputs (CV-A, CV-B, and GATE) of the ER-101 so that you can monitor your
performance in real-time.

18
CV/Gate trigger vs Gate-only trigger
A conguration screen is shown whenever you arm a track for real-time recording.
This screen has the following options:
Display Purpose Range Default
CV-A Trigger a new step when CV-A changes? tr, -- tr
CV-B Trigger a new step when CV-B changes? tr, -- --
DURATION Quantization grid for step durations. 1-99 1
GATE Quantization grid for gate lengths. 1-99 1
This screen disappears when you press the (ashing) ARM button once more. The
CV-A and CV-B options aect how a new step is created and are set by pressing the
FOCUS buttons next to the CV-A and CV-B displays.
Normally, during real-time recording a new step is only started when a rising edge
is received from the gate input, AD-1. However, there are cases when a new step
should start without a new gate signal such as when the performance includes lega-
to notes. Setting the real-time conguration for CV-A or CV-B to“tr” will cause new
steps to be created whenever the pitch CV changes (post quantization). The default
setting is to enable this option for CV-A but disable it for CV-B because it is assumed
that CV-A will usually be controlling pitch and CV-B will usually be controlling some
other non-pitch parameter such as velocity. If this is not the case then you can
change the behavior in this screen.
Duration and Gate Quantization
The next two options allow the user to specify the granularity of the quantization
grid. Steps that are recorded will have their DURATION and GATE parameters round-
ed to the nearest multiple of these quantization settings. The default setting is 1,
the minimum amount of quantization. Set the desired quantization by focusing the
DURATION or GATE display and turning the RIGHT knob.
Recording Focus
The ashing LED in the conguration screen indicates the current recording focus:
Focus Behavior
TRACK New material is inserted at the end of the track in a new pattern.
PATTERN New material is inserted after the current track in a new pattern.
STEP New material is inserted after the current step in the existing pattern.
This gure shows the conguration screen for real-time recording. In this case, new
steps would be generated only when a new gate is received or CV-A changes. The
step durations are quantized to multiples of 8. The recording focus is set to TRACK.
This gure portrays how a raw CV and gate pair are converted to a sequence of
steps. The pink overlay shows the extra step that would be generated if a change in
CV-A was congured to trigger new steps.

19
Step mode
The purpose of step recording is to use an external CV/gate source (such as a CV/
gate keyboard) to insert and delete steps but ignore the timing with which you do it.
The STEP record mode essentially places the ER-101 under remote editing control.
Unlike the other two recording modes, this mode inserts/deletes steps at the edit
cursor, not the play cursor. It helps to think of the STEP recording mode as really
just another editing mode. So if you want to see what you are doing you should put
the ER-101 in EDIT mode. Also, while recording in STEP mode, you can seamlessly
use the controls on the ER-101 to make additional edits or move the edit cursor to
another location.
The A-1 and A-2 analog inputs are as always routed to the CV-A and CV-B step pa-
rameters, respectively. The AD-1 input is placed in analog mode and is routed to the
GATE parameter. The AD-2 input is also placed in analog mode and is routed to the
DURATION parameter. D-1 takes a gate signal from your controller that triggers step
insertion and D-2 takes a gate signal that triggers step deletion.
Once you punch in, all armed tracks will be under remote control. A rising edge on
D-1 (insert) will cause a new step to be inserted at the edit cursor of all armed tracks.
So before you start recording, make sure you move the edit cursors of all armed
tracks to where you want new steps to be added. The step parameters of a newly
inserted step are set according to the voltage levels present at A-1 (cv-a), A-2 (cv-b),
AD-1 (gate), and AD-2 (duration):
Step Parameter Input Relationship
CV-A A-1 Quantize voltage with table A
CV-B A-2 Quantize voltage with table B
DURATION AD-2 (voltage)*20 (max 99 at 5V and over)
GATE AD-1 (voltage)*20 (max 99 at 5V and over)
As long as the D-1 (insert) gate is held high, the step parameters of the just inserted
step will follow any voltage changes as dictated by the table above. The step pa-
rameters are locked and will no longer change when the D-1 (insert) gate goes low.
Since steps are added at the edit cursor, you can have the sequencer playing (and
looping) the same section as you add/remove steps.

20
Alter mode
This mode is similar to the REAL-TIME mode in that steps under the play cursor are
aected and recording happens in real-time. However, no new steps are inserted in
the armed tracks. Instead, step parameters are overwritten with new values that are
derived from the input voltages. The step parameters are rewritten just before the
play cursor encounters the step and then plays it. If you are looping a single step
then the currently playing step and the next step about to be played are the same
step. In this case, voltage changes are reected immediately.
Except for the D-1/D-2 inputs which are not used, the jack mapping and relationship
between voltages and step parameters is the same as in the STEP recording mode:
Step Parameter Input Relationship
CV-A A-1 Quantize voltage with table A
CV-B A-2 Quantize voltage with table B
DURATION AD-2 (voltage)*20 (max 99 at 5V and over)
GATE AD-1 (voltage)*20 (max 99 at 5V and over)
The typical useage scenario for the ALTER record mode is to lay down new automa-
tion or melody on an existing sequence of steps. However, there are many unusual
and interesting possibilities that can lead to complex results when using non-synced
LFOs or even feedback from the ER-101 itself.
Congurable Option: The unused D-1 and D-2 inputs can be congured to control
other aspects while in this mode. See the conguration le on your SD card for
more details.
Example: Knobby Interface
A particularly useful setup is to synchronize a traditional analog step sequencer with
the ER-101 but have all of the analog step sequencer’s outputs go through the ER-
102 in ALTER record mode. If the ER-101 is looping a section that is the same length
as the sequence of steps on the analog step sequencer then you get a real-time
knobby interface for the loop playing on the ER-101 with pitch quantization! In
fact, now you have all the capabilities of the ER-101/102 added to your analog step
sequencer.
−10 −5 0 5 10
0 20 40 60 80 100
VOLTAGE
GATE or DURATION
gate,duration = oor(voltage*20)
maximum:99
minimum:0