Halloween Builds
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here are countless ways of
adding sound effects to the
project, but one of our
favourites is using a Bare
Conductive Touch Board. This
is a great choice for two reasons.
Firstly, it’s incredibly easy, and
secondly, sounds can be triggered
with touch input, which makes it perfect for reactive
sounds. This board is designed to work with
conductive ink – and it does this really well –
but it works equally well with anything conductive.
The pads are large enough for crocodile clips.
Your board should come pre-programmed with
the Touch MP3 sketch, but if it doesn’t (or you’ve
previously pre-programmed it to do something
different) you can download the code from
hsmag.cc/UiCkAv. You can use this in the Arduino
IDE (see here for how to set it up for the Touch
Board: hsmag.cc/bGGeqn).
Once the code is uploaded, you’re ready to go.
There are three touch-sensitive pads down one
side of the board labelled E0 to E11. Each of these
triggers an MP3 file on the microSD card to be
played. E0 will trigger file TRACK000.mp3, E1 will
trigger TRACK001.mp3, etc. All you have to do is
create MP3 files with the sounds you want and load
them onto the microSD card.
The Touch Board includes almost everything you
need for your sound effects, but it doesn’t have a
speaker. Any speaker that plugs into the headphone
port should work. You can get small portable
speakers that are great for little sounds, or you can
hook it up to a large hi-fi or PA system if you really
want to shock people.
The other thing you’ll need is a way of triggering
the sounds. The pins are touch-sensitive, and this
transmits along wires, so if you attach a crocodile
clip to the pin, touching the other end of the wire
will trigger the sound. If you attach the other end of
that crocodile clip to something conductive, then
touching that will trigger the touch sensor. There’s
no easy way to calculate exactly how long this chain
of conductive things can be before it stops being
touch-sensitive, but the shorter the better. You might
need to turn the board off and on again after
attaching wires to recalibrate the touch sensors.
T
Touch the
pad and
the sound
is played
- audio
effects the
easy way