neutral labs ELMYRA 2 User manual

ELMYRA 2 v2.1
by neutral labs
Manual
Hello, owner.
ELMYRA 2 is a digital/analog hybrid platform for microtonal sonic
exploration, capable of creating anything from lush ambient
soundscapes to gritty droning textures and shrieking noises, available
as a Eurorack module or semi-modular desktop synth. The included set
of preset cards or individual electronic components like capacitors or
diodes can be used to change the sound character.

Specifications
●Width: 42 HP
●Supply voltage (either):
○Eurorack 10-pin header: +12V/-12V
○USB power: +5V
●Current draw:
○Eurorack
■+12V: typ. 65 mA, max. 100 mA
■-12V: unused, 0 mA
■5V: unused, 0 mA
○USB
■typ. 75 mA, max. 120 mA
●CV inputs: 0V to 3.3V usable, -12V to 12V max.
●Utility inputs: 0V to 5V usable, -12V to 12V max.
●Audio input: ideal 3V-10V, max. 15V peak-to-peak (mono)
●Audio output: 4V peak-to-peak (mono)
Connecting ELMYRA 2 to USB power
Connect the provided USB-A-to-USB-C cable (or any other such cable) to
a USB power source. Unlike typical USB-A jacks, the USB-A connector of
the provided cable is reversible. It may take a little more force to
fully insert on the USB-A side. The device will not work with a
USB-C-to-USB-C connection unless a USB-C-to-USB-A adapter is also
used. If you have previously removed the module unit from its case,
make sure the internal power cable is once again correctly inserted
into the white XH connector on the back of the board.
Connecting ELMYRA 2 to Eurorack power
Connect a 10-pin Eurorack power cable to the 2x5 power header on the
back of the module. There is an arrow indicator next to the word
STRIPE on the circuit board. Unsurprisingly, the red stripe side of
the cable goes on the side that says STRIPE. The module (and your
power supply) is protected in case you should ever connect it the
wrong way around, but it won’t turn on if you do.

First setup
Elmyra 2 contains some controls that can cause extreme types of sound,
or no sound at all. To make sure your first session will not be
frustrating, follow these steps before turning on the unit or module:
●Set MIX to minimum.
●Set RESO to minimum.
●Set CUTOFF to maximum.
●Set CHOKE to maximum.
●Set BITE to minimum.
●Make sure the master volume knob (top left) is not set to
minimum.
Hint: During your first session, you will notice that the mix of the 4
voices gets heavily saturated, because the OUCH circuit (described
further below) loves a saturated sound in order to do its thing. If
you’re looking for a more subdued ambient sound (or an even dirtier
one), you can adjust the saturation level (see Advanced settings).
Updating the firmware
For the desktop version, unplug the USB power cable and remove the 4
screws attaching the module to the case. If the power cable is
unplugged, the internal XH cable can remain in place. For the Eurorack
version, remove the module from the rack and unplug the Eurorack power
cable. Set the jumper connector on the back of the module to the
UPDATE position, connecting the middle and upper pin of the pin
header. Plug a Micro-USB cable into the Micro-USB socket on the back
of the module, and the other end of the cable into your computer. The
module will appear as a USB drive in your system, whether you’re using
macOS, Linux or Windows. Copy the provided update file (suffix .UF2)
onto this drive, which should only take a few seconds. Unplug the USB
cable, put the jumper connector back into the NORMAL position, place
the module back into its case or rack and enjoy the new functionality
(and possibly fixed bugs)!

Main signal flow
Elmyra 2 has 4 identical voices that are mixed together with the mix
getting saturated. The level of saturation is adjustable (see Advanced
Settings) for softer or even dirtier sounds. This mix is then sent
through a resonant low-pass state variable filter (LPF) – that can be
changed to various other filter types (see Advanced Settings), and on
to a delay. (Optionally you can add a lo-fi reverb after the delay,
see Advanced Settings). The delay output gets mixed with any external
audio that might be connected, and is sent through the OUCH effect,
which is an analog circuit containing a unique combination of
distortion, waveshaper and low-pass filter. The specific sound of this
effect can be modified using the modifier ports, which expose the
circuit’s feedback loop to the front panel. The final result is then
adjusted in volume by the volume knob and sent to the audio output.

Voices
Control
Function
Touchpads
The metal pads at the bottom of the unit react to the touch
of a finger (both pads of a voice must be touched). They
modulate the volume of the voice depending on the intensity
of the pressure as well as the conductivity of the skin
(extremely dry skin will result in a lowered volume). An
orange LED beneath the pads indicates the current volume as
set by the envelope.
The touchpads also generate a CV signal that is available
via the voice’s ENV output.
GATE
This input simulates the touch of a finger on the voice’s
touchpads. It is not strictly a gate in the on/off sense,
but rather continuous. A higher voltage will simulate a
more intense pressure on the pads.
ENV
This sets the attack and release times for the voice’s
envelope. In the counterclockwise position, the attack time
is short, with the release time slightly longer. Attack and
release time increase as the knob is turned further
clockwise. The resulting envelope affects voice activation
by touch as well as activation via the GATE input.
PG
A short press of this button cycles through the 4 available
wavetable pages.
A long press (> 1 second) sets the voice to drone mode –
where the envelope is continuously at maximum – or exits
drone mode. During drone mode, the envelope is decoupled
from the voice. The envelope LED will not light up
continuously, but the touchpad and/or GATE input can now be
used to generate a CV signal that is available via the
voice’s ENV output, without affecting the voice’s volume.
(Another way to get the voice to drone is to patch a cable
between the same voice’s ENV output and GATE input. This
will cause the LED to light up.)
The PG buttons have a number of secondary functions (in
combination with other controls) which are explained in the
relevant sections of this manual.
WAVE
This sets the position in the current wavetable page used
to generate the main waveform for the voice’s oscillator.

MOD
This sets the amount of the current MODP voice modulation
program. In the counterclockwise position, the voice will
always be clean (unaffected by the modulation), unless the
low-pass filter MODP effect is selected, in which case the
voice will be clean in the clockwise position. The MODP
programs are described in detail in a table further below.
TUNE
This sets the frequency of the voice, which can be changed
either continuously or in quantised (chromatic) fashion,
according to the current CHRM setting. Microtonal scales
are supported, as is portamento, see Advanced Settings.
The corresponding CV input follows the Eurorack 1V/octave
standard. While a jack is connected to the input, the TUNE
knob has no function.
Left side buttons
Control
Function
SYNC
This button can be pressed multiple times in order to tap
in a tempo for the internal clock. This clock tempo will
then be used in the sequencer (and optionally for syncing
the delay time or LFOs, see Advanced Settings). The LED
will flash in sync with the clock while the clock tempo is
set. You can unset the tempo (and stop the flashing) by
pressing this button for more than 1 second. Instead of
tapping in a tempo, the socket above the button can receive
a continuous clock signal from an external source.
MODP
There are 9 MODP programs, each of which will modify the
plain oscillator output of a voice in different ways. The
intensity of the selected effect is determined by the
voice’s MOD knob setting (and/or its MOD CV input).
Pressing and releasing the MODP button will cycle through
those 9 programs. When doing this, the program is changed
globally across all voices.
If you want to change the program for a single voice only,
press and hold the voice’s PG button, press MODP repeatedly
until the desired program is selected, and release the PG
button. (The PG button will not execute its other functions
of changing the wavetable page or enabling drone mode in
this case.)

If you changed the program for a single voice only, the
MODP LED will blink in the color of the last selected
program to remind you that the settings are now different
across the voices.
This can be repeated for other voices, so each voice can
have a different MODP effect (but the LED will only blink
in the color of the last selected program). Pressing and
releasing MODP normally will align the voices again, and
cause the LED to stop blinking. (It will also stop blinking
in case you set all 4 voices to the same program
individually.)
CHRM
Pressing this button will activate/deactivate chromatic
mode. The LED lights up while chromatic mode is active.
In this mode, the TUNE knobs are quantised to the notes of
the 12-tone equal temperament chromatic scale, based on
A=440 Hz. This makes it easy to play chords and other
harmonic structures, and also play in tune with other
instruments. You can also set the scale to one of several
microtonal scales instead, see Advanced Settings.
Chromatic mode can also be activated/deactivated
selectively per voice. Press and hold any PG button, press
and release the CHRM button, and release the PG button
again. (The PG button will not execute its other functions
of changing the wavetable page or enabling drone mode in
this case.) Chromatic mode will be toggled for this voice
only. The LED will blink as long as chromatic mode is only
activated for some of the voices. You can at any time press
the CHRM button in order to align all voices again.
(Hint: If you want to avoid the audible stepping of notes
while adjusting the TUNE knob in chromatic mode, but still
want the tuning to be quantised once it settles on a note,
portamento can be used, see Advanced Settings.)
REC
Press and release the REC button in order to start
recording a sequence of TUNE settings on voice 1. Or press
and hold any combination of voice PG buttons, then press
and release the REC button to start recording sequences on
all of those voices. Each voice has its own sequence memory
and the recording of sequences can be done in parallel or
one after another. Stored sequences are not persistent
across device restarts. The maximum number of steps per
voice is 128.

The step length is arbitrary, so you could e.g. record a
looping 3 step sequence on voice 1 and a looping 7 step
sequence on voice 2 (if you record them one by one).
While the REC LED is lit up, press and quickly release the
REC button to record one step (the current TUNE setting for
the voice or voices) and advance to the next step. The LED
will blink once to confirm. Repeat as desired.
While the REC LED is lit up, press and hold the REC button
for more than 1 second in order to end and store the
recording. You may also press and release the PLAY button
to end and store the recording and start playback.
While the REC LED is off, you may press and hold any number
of PG buttons and then press and hold the REC button for
more than one second in order to delete the recorded
sequence for those voices. The REC LED will blink once to
confirm, after the REC button is released.
PLAY
Press the PLAY button in order to start looping sequence
playback for all voices that have a sequence in memory.
Press it again in order to stop playback.
Note: The sequencer records only the voice TUNE setting, it
does not record or output gates. In general, you will want
to put the sequenced voices in drone mode (by long pressing
on their PG buttons) during playback and recording,
although it can be an interesting effect to play the
sequenced voices manually via the touchpads. If you want
gates or rather envelopes, try synchronizing one of the
LFOs to the clock (see Advanced settings) and use it to
modulate either the main filter, the GATE input or the MOD
input while on the LPF MODP setting.
Note: The sequencer will not initiate playback unless a
clock speed has been tapped in via the SYNC button or a
clock signal is connected to the corresponding input. The
SYNC LED will flash with the internal or external clock
pulse if either is the case.

LPF (low-pass filter)
The default main filter is a resonant 2-pole state variable low-pass
filter. The mix of all 4 voices passes through this filter and is then
sent into the delay. It is possible to switch to one of several
alternative filter types: a 4-pole ladder filter or a 2-pole state
variable filter in band-pass or high-pass configuration, see Advanced
Settings.
Control
Function
RESO
This changes the resonance of the filter. In the
counterclockwise position, there will be no resonance. In
the clockwise position, the resonance is at maximum.
CUTOFF
This changes the cutoff frequency of the filter. If set to
the default low-pass filter: In the counterclockwise
position, the sound will be almost completely cut off. In
the clockwise position, the filter is completely open.
Delay
Control
Function
TIME
This sets the delay time, with the shortest time in the
counterclockwise position and the longest time in the
clockwise position (about 1.6 seconds). The delay time can
be synchronised to the clock, see Advanced Settings.
FDBK
This sets the amount of feedback. In the counterclockwise
position, there is no feedback added to the delay. Around
the middle position, the feedback is at 100%, increasing
even further towards the clockwise position.
There is a saturator in place that keeps things (mostly) in
control even while at crazy feedback levels. Still, in
certain cases it’s possible for the audio signal to break
up due to too much feedback. This occurs gradually, and as
you start noticing it, you can try changing the delay time,
the waveforms or the tuning of the voices slightly in order
to prevent it. If this fails, you’ll want to dial back the
feedback setting, and then slowly increase it again.

MIX
This determines the wet/dry mix of the delay effect. In the
counterclockwise position, you’ll hear only the dry signal
and the delay has no effect. In the clockwise position, you
will only hear the delay effect without the dry signal.
OUCH
This is a special analog circuit – a unique combination of
waveshaping, distortion and filter that is able to wreak havoc on the
sound, if you so desire.
With BITE set to minimum and CHOKE set to maximum, the sound will pass
through unaffected.
The modifier ports that are exposed on the front panel to the right of
the knobs can be used to customize the sonic qualities of this circuit
by using the included preset cards (or other Neutral Labs preset
cards), or individual electronic components like diodes or capacitors.
This is described in its own chapter below (see Modifier Ports).
Control
Function
CHOKE
This control filters the sound: The filter will be closed
when turned fully counterclockwise. With BITE turned
partially or fully up, CHOKE will affect the phase of the
signal and create weird artifacts in the sound at certain
settings.
Turn the control fully up (clockwise) to disable it.
The BITE control loves to be modulated at audio rates via
an LFO (turn the BITE knob almost fully up and set the LFO
close to maximum speed).
BITE
This control shapes and distorts the sound and adds
harmonics in the high frequency range. Turn fully down
(counterclockwise) to disable it. Turning it up beyond the
middle position makes it more and more destructive, to the
point where depending on the current sound’s
characteristics and volume, the output may break down
completely. This can be counteracted by turning down the
CHOKE control.