neutral labs ELMYRA 2 User manual

ELMYRA 2 v2.1
by neutral labs
Build Guide
Elmyra 2 comes with all SMD components presoldered, and as such it is
a very straightforward build. Due to the large number of front panel
components, it will take some time though (1-3 hours depending on
level of experience). Some of the soldering will be in close proximity
to SMD parts, so care must be taken. The kit is intended for builders
of medium or advanced skill level, but can be completed by a motivated
and careful beginner (with some previous soldering experience). Please
read and follow the guide thoroughly!

Component List (common parts for Eurorack + desktop)
Part ID
Count
Type
Polarity
matters?
J3
1
10-pin power header
no
J5, J8-J47
41
Thonkiconn mono 3.5 mm switching socket + nut
-
J6-J7
2
long-legged 5-pin header (panel ports)
no
D9, D10, D39, D40
4
LED 3 mm orange (orange body)
yes
D3, D13, D16, D19
4
LED 3 mm orange superbright (clear body)
yes
D41
1
LED 3 mm green (green body)
yes
D42
1
LED 3 mm red (red body)
yes
D43
1
LED RGB 4-pin (white square body with dome)
yes
SW1-SW9
9
SPST momentary button
no
RV1-RV6
6
100 kΩlinear potentiometer + nut (metal shaft)
-
RV7-RV31
25
100 kΩlinear potentiometer (plastic shaft)
-
-
8
button cap black
-
-
1
button cap red
-
-
8
stainless steel touchpads M3
-
-
8
plastic washers M3
-
-
8
brass nut M3
-
-
5
brass spacer M3
-
-
6
knobs for RV1-RV6
-
-
1
“Pets” set of 4 preset cards
-

Component List (desktop kit only)
Part ID
Coun
t
Type
Polarity
matters?
J4
(1)
XH header
yes
-
1
XH power cable
-
-
4
hex panel screw
-
-
4
square nut for hex panel screw
-
-
1
USB-C to USB-A cable
-
Component List (Eurorack kit only)
Part ID
Coun
t
Type
Polarity
matters?
-
4
panel screw
-
-
1
Eurorack power cable
-
Step-by-step instructions
Put the 8 plastic washers onto the 8 touchpad screws. Insert the
screws into the holes on the bottom part of the front panel and secure
them from the back as follows: Each upper row screw is attached with a
brass spacer, and the bottom row screw of voice 1 (on the left side
when viewed from the front of the panel) as well. The remaining 3
bottom row screws are simply attached with a brass nut each. Tighten
the spacers and nuts well, as they’re also making electrical contacts.

Snip off the little anti-rotation tabs near
the bottom of RV1 to RV6 with a wirecutter
(these are the green metal pots).
Now on to the PCB. Insert the 10-pin Eurorack power header (J3) and
solder from the other side. This header is part of both the Eurorack
and desktop version of the kit, as desktop version users may want the
option to rack their Elmyra 2. It’s best to solder 1 pin first,
correct the angle slightly if necessary, then solder the remaining
pins.
Only the desktop
version has an XH
connector for USB power
(J4). Put it in place
and solder. Double
check the orientation!
The open slot goes on
the side towards the
middle of the PCB, as
indicated on the
silkscreen print.

Now flip the PCB over and put in the 9 switches (SW1-SW9) and their
button caps without soldering yet! The red cap goes on SW4, all others
receive a black cap.
Insert the Thonkiconn sockets and pots. It is best to do this row by
row, so you have enough space around the components. RV1 to RV6 are
green metal pots, all other pots are black plastic minipots. Hold the
PCB on the edges or place it on supports, so you do not accidentally
move the components before soldering. Also insert the two 5-pin
headers (J5-J6). Then insert all the LEDs as described below. The long
legs of the LEDs go on the side marked on the PCB with a “+”. Double
check the orientation!

The orange LEDs go into D9-D10, D39, D40. The red one goes into D42
and the green one into D41. The 4-legged RGB LED goes into D43. One of
its legs is longer than the others, that one goes into the hole marked
with a “+”. The 4 clear LEDs are a super bright orange type used to
light up your fingers from below the touchpads, and they go into the 4
LED footprints at the bottom of the PCB. Do not solder anything yet!
Now that all the components are in place, it’s time to combine front
panel and PCB. Make sure all inserted components are standing up
straight and carefully place the front panel onto the PCB, keeping
both of them parallel to each other and making sure all the components
find their way through the holes. The spacers behind the touchpad
screws need to go through the holes on the PCB. Don’t worry about the
two 5-pin headers at this time. Once everything fits together neatly,
secure RV1 to RV6 with nuts from the top. Flip everything over and
attach the 5 remaining brass nuts to the 5 spacers protruding through
the PCB. Tighten them well, as they make electrical contacts, but be
careful: Right next to them are some very small SMD components that
are easily damaged, so do not push your wrench or pliers down towards
the PCB while securing the nuts!
Place the front panel face down onto some sort of support on the
sides. If you’re building the desktop version, you can simply lay it
face down into the case. This is to make sure that all Thonkiconn
sockets will sit close to the front panel. Now solder all pins on the
Thonkiconn sockets and switches, but do not solder any pins on the
pots, LEDs or 5-pin headers yet! While soldering, pay close attention
to those areas that have a high concentration of SMD parts. There is
always enough space to solder the pins even with a standard tip, but
care must be taken not to accidentally move the iron and desolder,
move or damage an SMD part.

Remove the module from the supports or case and lay it face down on an
evenly flat surface. This ensures that the plastic pots are pushed
back against the PCB. Solder the pins of all the pots now (both metal
and plastic pots).
For D3, D13, D16, D19 (the clear LEDs between the touchpads), pull up
their leads as far as they will go and spread them apart, bending them
about 45 degrees to the sides. This should set the LED body flush with
the PCB, so it is as far away from the front panel as possible. Now
solder those legs and snip them off with a wirecutter. Make sure the
LED bodies are pointing straight up.
Attach and tighten all the Thonkiconn socket nuts, or at least those
that are close to any LEDs and the 5-pin headers (J5-J6). This ensures
a constant distance between PCB and front panel which is important for
soldering the LEDs and 5-pin headers.
All other LEDs should now sit as close as possible to the front panel.
Each also needs to be positioned in the middle of the viewport on the
front panel, pointing towards it. The best way to ensure that is as
follows: Apply some solder to one of the LED legs and its solder pad
while keeping the iron in place (not longer than about 2 seconds at a
time or the LED might take damage). Grab the LED legs with a pair of
tweezers or pliers and move the LED while the solder is hot, carefully
pushing it against the front panel and centering it behind the
viewport (check by peeking in from the side). Remove the soldering
iron while leaving the tweezers in place. Remove them once the solder
has solidified (after a few seconds). You can repeat this process if
needed. Once you’re satisfied with the position, solder the other
leg(s) of the LED normally. Cut the LED legs after you’re done.

Now push the two 5-pin headers (J5-J6) into the slots on the front
panel, so that they sit flush with the surface. For aesthetic reasons,
they barely fit, so this may take some wiggling. Put some tape over
the slots from the front side. Solder only the middle pin of each,
taking care not to touch any of the SMD components in the vicinity
with your iron. Remove the tape to check the positioning. If there is
an angle in one of the headers, reheat the solder and readjust. Put
the tape back on and solder the remaining pins, again being mindful of
the SMD components. You may then snip off the protruding part of the
legs, but it’s not necessary.
For the desktop version, take the XH cable and solder its 2 wires to
the 2 solder lugs on the USB-C socket on the back of the case as shown
(red wire goes on the left side when viewed from the inside of the
case).
Now plug in and test your module. For the Eurorack version, use the
provided Eurorack power cable. For the desktop version, insert the XH
cable from the case into the XH header (J4) on the back of the module,
and power the case via the USB-A-to-USB-C cable.

If something’s not right upon power-up, it may be best to unplug the
module from power immediately so as not to damage it (or the PSU),
even though that’s pretty unlikely.
Make sure to test the functions of all the potentiometers and buttons.
Refer to the manual if needed.
Most problems can be easily fixed by reheating all your own solder
joints so the solder can reflow. Also visually inspect joints and see
if you can spot accidental solder bridges.
When everything is working correctly, you can now put the knobs on the
shafts of RV1 to RV6.
You may want to check the website for firmware upgrades before putting
the device to use. The firmware upgrade procedure is described in the
manual.
For the Eurorack version, place your new
module in a rack. For the desktop version,
insert the 4 square nuts into the 4 slots in
the corners of the case. Put the module on
top and secure it with the 4 black hex
screws, or any other M3 screws (such as those
commonly used for Eurorack).
There is a 1V/octave pitch calibration routine outlined in the manual.
In most cases, you’ll simply want to set the defaults for either the
desktop version (using code 213) Eurorack version (code 214).
Congratulations, you’ve now completed the build. Go and make some
beautiful noise! If there are any questions or issues, feel free to
reach out anytime at [email protected].