Loopcard THE DIY LO-FI AUDIO LOOPER User manual

THIS KIT CONTAINS
1x wooden enclosure (7 pieces)
1x ISD1820 sound module
1x 2*AAA battery holder
1x 1/8 inch female jack socket
2x ON/OFF toggle switches
2x momentary push buttons
1x 5539 photoresistor
1x 470K resistor
TOOLS NEEDED
Soldering iron and solder
Set of pliers: cutting, at and
stripping
Hot glue gun or superglue
Flat headed screwdriver and
small wood le*
* : optional
NOT INCLUDED IN THIS KIT
2x AAA batteries, 1/8 inch audio cable and monitoring system (earbuds,
amplied speaker, etc.)
A FEW TIPS FOR BUILDING THIS KIT:
- Find a suitable place to solder: quiet with a large clean surface. Because of
solder fumes, keep the room well ventilated.
- Read all the instructions before starting. Make sure you have all the
components and tools listed above. Read the instructions of the tools you will
use, such as the soldering iron.
- Solder the component on the back of the sound module, as shown on the
schematics.
- Before soldering, mount the components on the enclosure faceplate. This will
help you cut the right length needed for the wires. Wires that are too long can
be as inconvenient as wires that are too short!
- Solder wires at a 90° angle to the components legs to save space in the
enclosure.
- Depending on your soldering skills, you might want to watch tutorial videos
on soldering and practice on old components.
- You can test your circuit between steps, but remember to always remove the
batteries when soldering!
Watch the video tutorial:
www.jeanbaptisteleveque.fr « Instruments »
Ready? Let's go!
Thank you for purchasing this Loopcard kit, the do-it-yourself lo- looper.
Record your voice, an instrument, the neighbor's dog or any sound
with the built-in microphone!
Play back and loop your recordings with the PLAY and LOOP functions!
Create new sounds with the SPEED function and control the speed of
recording and playback with the light sensor!
The Loopcard is an electronic musical instrument designed by
Jean-Baptiste Lévêque, around the ISD1820 sound recording module.
This document will provide all the information needed to build and use
your Loopcard. For any inquiries, feel free to write at:
leveque.jeanbaptis[email protected]
THIS KIT SHOULD NOT BE BUILT WITHOUT ADULT SUPERVISION
A word of the designer
With the Loopcard, I wanted to design an original and open instrument,
both easy to build and to use.
Its minimal interface was designed to be as intuitive as possible. It oers a
chance to experience the building blocks of electronic music: sampling,
looping and live sound manipulation.
THE DIY LO-FI
AUDIO LOOPER
AUDIO: The audio output. You can plug in headphones, speakers, etc.
This is a mono output. Sound will only come out of the left side on a stereo
system.
MIC : The built-in microphone. Talk in it or point it toward the sound source
you want to record.
REC : Hold this button and talk in the microphone to record. Recording
stops when you let go of the button or when memory is full (10 seconds
approx.). Each new recording will erase the previous one (no overdubbing).
PLAY: Hold this button to play back your recording.
LOOP: Turn this switch on to play your recording in an endless loop. Keep
this switch o when recording or when you are not using your Loopcard.
SPEED: Turn this switch on to activate the light sensor (photoresistor) on
the right. The amount of light this sensor gets will change both the
playback and recording speed. Lot of light will speed up playback and
shorten recording time (but with a better sound quality). Less light will slow
down playback and lengthen recording time (but with a poorer sound
quality).
Try waving your hand in front of the sensor, obscuring it during playback
and recording to create really weird sounds!
HOW TO USE YOUR LOOPCARD

1
2
3
1 2 3
SPEED
o on
o on
BLA
BLA
BLA
PLAYE PLAYLREC
1
2
3
4
5
2 AUDIO OUTPUT
Solder two wires between the
outer legs of the jack socket and
the two points of SP1 (the white
connector on the module). No
polarity here, you can solder them
any way you want.
Depending on the jack model, the
legs may look dierent. Refer to
the schematic to know how to
solder your jack.
3- LOOP
Solder two wires on the legs of a
toggle switch. Solder the two other
ends of the wires on the P-E points
on the module. These points are
located on the same two-columns
ensemble of points where VCC and
GND are.
Test the toggle switch. One
position starts playing and looping
your recording, the other stops it.
4A - SPEED
Solder 3 wires on 3 the points of
the chip holder, as shown on the
schematic. Use dierent wire
colors and note how they are
numbered.
Integrated circuits such as the ISD
chip are very sensitive to heat. We
removed it from its support so that
we can solder on it without
damaging the chip.
4B  SPEED
Mount the other toggle switch and
the photoresistor on the enclosure
faceplate. The switch goes in the
SPEED hole and the photoresistor
legs go through the two small holes
on the right.
Directly solder one leg of the photore-
sistor and one leg of the resistor to one
leg of the switch. Solder the wires
following the schematic.
5- REC and PLAY
To replace the small buttons on the
module, solder the two buttons on
the REC and PLAYL points on the
module using two pair of wires,
following the schematic. Again, no
polarity to worry about here.
Your circuit is complete ! Put the
batteries and the ISD back on its
support, and try the various
switches and buttons.
TEST YOUR CIRCUIT
- Plug headphones or amplied
speakers into the audio jack.
- Hold the REC button and speak in
the microphone. Let go of the
button.
- Press PLAYE. You should hear
your recording in full.
- Press and hold PLAYL. You should
hear your recording as long you
hold the button.
1 POWER
Solder one wire between the
positive leg of the battery holder
and the VCC solder point on the
module, and one wire between
the negative leg and the GND
point. Be careful of the polarity!
Put the batteries in and hold the
REC button. A red led should light
up. If not, check your connections
and the batteries.
THE FINAL CIRCUIT
REMOVE THE CHIP
Carefully remove the ISD chip
from its holder. Use a plier or a
small at-headed screwdriver, to
progressively lever the chip out of
his holder from each side.
Note the orientation of the chip
with its writing and circular
markings. Keep it safe in a little
cup or a tray while you nish the
circuit.
BUILDING THE ENCLOSURE
Before getting started, you can use adhesive tack to temporarily assemble your
enclosure. When using glue, let it dry between each step.
1- Mount all components on the faceplate.
Put the switches in the same way.
For example: lever up to turn ON, lever
down to turn OFF.
2- With the two pairs of bolts
and screws, install the ISD
module below the faceplate,
the MIC facing its hole.
3- Glue the four sides and
the transversal « beam »
together by applying small
drops of glue on the inside,
where the edges meet.
4- Glue the faceplate on
top of the four sides, the
hole for the audio jack
toward the back.
Mount the audio jack
socket on its hole.
5- Once everything is in place,
put the batteries back on and put the
battery holder in the enclosure. Slide the
bottom panel in the slots to close the enclosure.
Do not glue the bottom panel!
You will need to remove it for changing the batteries, for repairing or
modyng your Loopcard.