neutral labs ELMYRA V1.3 User manual

ELMYRA v1.3
by neutral labs

Manual
Hello, owner.
Congratulations on building, buying or stealing the mighty Elmyra. You
may not know it, but this device will change your life forever, if it
hasn’t already. For the best possible experience, please read this
manual carefully to the end. Actually, there might be one of those
hidden clauses in there, where you win a prize because you’re the
first person reading it. I’m not saying there is, but you won’t know
unless you read it, right?

Disposal
For private households: This symbol (figure on the
right) on the product(s) and/or accompanying
documents means that used electrical and electronic
equipment (WEEE) should not be mixed with general
household waste. For proper treatment, recovery and
recycling, please take this product(s) to
designated collection points where it will be
accepted free of charge. Alternatively, in some
countries, you may be able to return your products
to your local retailer upon purchase of an
equivalent new product. Disposing of this product
correctly will help save valuable resources and
prevent any potential negative effects on human
health and the environment, which could otherwise
arise from inappropriate waste handling. Please
contact your local authority for further details of
your nearest designated collection point.
Penalties may be applicable for incorrect disposal of this waste, in accordance with
your national legislation.
For professional users in the European Union: If you wish to discard electrical and
electronic equipment (EEE), please contact your dealer or supplier for further
information.
For disposal in countries outside of the European Union: This symbol is only valid in
the European Union (EU). If you wish to discard this product please contact your
local authorities or dealer and ask for the correct method of disposal.
Please think of our planet! Repair, resale or upcycling are always better than final
disposal.
Specifications
Dimensions: 230 mm x 170 mm x 85 mm
Weight: 690 g
Supply voltage: 5 V (USB)
Current draw (max.): 500 mA
Audio output: mono (TS) 6.35 mm (1/4 “) phone jack

Connecting Elmyra
Elmyra comes with a USB power cord that has a USB A connector on one
end and a 5.5 x 2.1 mm DC barrel plug on the other end (ring is
negative, tip is positive). It operates on 5 V of DC voltage and can
conveniently be powered by any mobile phone charger, USB hub, laptop
or even by a USB power bank on the go.
The audio output uses a standard 6.3 mm (¼ inch) mono (TS) jack. Plug
it straight into your mixer, audio interface, effects unit or powered
speakers.
CAUTION! Plugging headphones directly into the audio output is not
recommended as they present a much lower input impedance which the
circuit is not made for. Plainly speaking, in the best case the sound
will be very quiet and in the worst case you might damage your Elmyra.
Signal Flow

Front Panel
Elmyra’s front panel has 3 sections: The voices (x3), the top row and
the scratch/bite distortion circuit.
Feel free to experiment on your own, but in case you want to know
exactly which input does what, check the reference below.
Position 1 and position 2 refer to the switch positions, which are up
(1) and down (2) if you bought a complete Elmyra. For DIY projects,
these may be reversed depending on the wiring, or even left/right. It
should be easy to figure out though.
Input
Primary function
Secondary function
SHAPE
Changes the waveform for this
voice. Position 1 is “almost
sawtooth” and position 2 is “not
Enable chromatic
and sequencer modes
(see below).

quite square”.
ENV
Changes the envelope attack and
release length for this voice.
Position 1 is long, position 2 is
short.
Enable drone mode
(see below).
TUNE
Changes the frequency of the
voice. This can be either a
smooth change, or steps between
notes if in chromatic mode.
-
TOUCHPADS
Touch the upper and lower pad at
the same time to trigger a voice.
Depending on the pressure and
other factors, such as the
resistance of your skin, the
volume is increased or decreased.
So account for excessive sweating
in case you get emotional while
playing Elmyra (a common
occurrence).
-
TIME
The delay time of the built-in
delay. If the feedback is high,
you can tune the delay time to
generate new frequencies on top
of the ones played by the voices.
To facilitate this, the TIME knob
is not linear: Its reaction is
more sensitive at low values.
The speed of the
step sequencer
during playback.
FEEDBACK
The amount of feedback for the
delay. If your Elmyra won’t stop
making noise even after the
envelopes have rung out, and for
some reason you want it to stop,
turn this knob down.
-
MIX
The dry/wet mix for the delay. At
50% setting, you’ll hear both the
delay and the original sound at
the same volume level. Turned up
fully clockwise, you’ll hear only
the delay.
-

MOD
When turned up, this introduces a
random modulation to the
frequency of each voice, but
unlike common LFOs this does not
vary slowly over time. Rather, a
new deviation value is chosen for
each cycle of the waveform. The
amount of deviation is controlled
with this knob. Turned fully
counter-clockwise, there is no
modulation.
-
FILTER
This is a low-pass filter that
takes off some of the high range
frequencies when turned down. You
might want to leave this knob
turned fully up by default and
turn down as desired when the
harshness introduced by the
distortion or excessive filter
feedback is too high for your
taste.
-
VOLUME
Much to the user’s surprise, this
knob controls the overall volume
of the sound.
It can also be used
to conjure up
various ethereal
entities. The exact
mode of operation
is left as an
exercise to the
user.
SCRATCH
This controls Elmyra’s nasty
distortion. The circuit is built
in such a way that a slight
amount of distortion is present
at all times, even if this is
turned down. Turn it up to
increase the nastiness.
-
BITE
This switch, when in position 2,
will add high overtones and noise
to the distortion. If the SCRATCH
knob is turned down, it will have
no perceivable effect.
-

Drone Mode
Flip any of the ENV switches twice quickly (within 1 second) to put
the corresponding voice in drone mode, meaning that it will ring even
if you’re not touching the touchpads. Another way of doing this is by
putting a coin across the touchpads, but be advised that using the ENV
switch is the cheaper method.
Chromatic Mode
Flip SHAPE switch of voice 1 (on the left) twice quickly to enter
chromatic mode. This mode is global and affects all voices. The
frequencies selected by the TUNE knobs will now be in steps according
to the chromatic scale, based on A4 = 440 Hz. The frequency range will
be extended upwards. The MOD knob will still affect the voice
frequencies as before.
Sequencer Mode: Recording
Flip SHAPE switch of voice 3 (on the right) twice quickly to enter
step recording mode. This will delete any previously recorded
sequence!
The sequencer will record the TUNE frequency for each voice per step
(only if this voice has its ENV switch in position 2), as well as the
setting of the TIME knob for each step. Voices that have their ENV
switch in position 1 will not be recorded, which means you can use
them to “solo” over your recorded sequence during playback.
Touch the touchpads for voice 1. Make adjustments to the TIME knob
and/or TUNE knobs as needed (you can touch the pads for voices 2 or 3
as well to check, or put them into drone mode during recording). When
you release the pads for voice 1, the step is saved and you can start
over with the next step in the same way. Up to 16 steps can be
recorded.

To leave recording mode, flip SHAPE switch 3 twice again, or
alternatively enter playback mode directly by flipping SHAPE switch 2
twice.
Sequencer Mode: Playback
Flip the SHAPE switch of voice 2 (in the middle) twice quickly to
enter playback mode.
The voices will now play back their recorded TUNE values step by step
and the TIME settings will be updated as well with each step. The
voices will not be triggered automatically! In order to hear the
sequence, you need to put voices into drone mode by flipping their ENV
switches twice, or alternatively play them manually via the touchpads.
Only voices that had their ENV switches in position 2 during recording
will change their TUNE values, so the other ones can still be played
manually during playback.
The TIME knob controls the sequencer speed in this mode.
Exit playback mode by flipping SHAPE switch 2 twice, or alternatively,
enter recording mode directly. With some practice, you’ll be able to
use recording and playback mode on the fly without interrupting your
performance.
Firmware Update
In case there is a firmware update available, download it from here:
https://github.com/neutral-labs/elmyra
Open up your Elmyra by removing the 4 screws in the corners of the
front panel. Find the micro USB connector on the circuit board inside.
Plug a USB A to micro USB B cable, such as is commonly used for

charging mobile phones, from your computer into the connector inside
Elmyra’s bowels. Be gentle.
Install and open Arduino IDE and install the SAMD21 libraries as
described here:
https://learn.adafruit.com/introducing-itsy-bitsy-m0/using-with-arduin
o-ide
Load the project into the IDE. Upload the sketch via the arrow button
on the top left. Wait until the LED inside stops flashing and there is
a message in Arduino IDE that says the upload was successful. Unplug
the cable, close Elmyra back up and enjoy the new firmware!
Hints
Elmyra rewards experimentation and playing it may be a very personal
experience. Nevertheless, here are some pointers to help you get
creative:
●Turn MOD fully down. Adjust TUNE of two or more voices so that
they’re very close to each other. Play them manually or put them
into drone mode. Now change the TUNE values slightly to get a
beating effect. Turn MOD up a bit for subtle effects.
●Set ENV time to short, TIME to somewhere over 50% and FEEDBACK
between 50 and 75%. Now play short phrases using the touchpads.
They will ring out via the delay.
●Set TIME and MOD to a low value and FEEDBACK to maximum. Trigger
some voices or put them into drone mode. Now introduce weird
timbres by turning up the MOD knob. Also try playing with the
TIME value.
●With the SCRATCH knob turned between 50% and 100% up, trigger the
BITE switch into position 2 (enabled) in short bursts. This works
especially well with external reverb and/or delay units.
●Put Elmyra into chromatic mode, set two or more voices to drone
and play some chords!