  Sound synthesiser controls typically correspond to technical parameters of
signal processing algorithms rather than intuitive sound descriptors that
relate to human perception of sound. This makes it difficult to realise sound
ideas in a straightforward way. Cross-modal mappings, for example between
gestures and sound, have been suggested as a more intuitive control mechanism.
A large body of research shows consistency in human associations between sounds
and shapes. However, the use of drawings to drive sound synthesis has not been
explored to its full extent. This paper presents an exploratory study that
asked participants to sketch visual imagery of sounds with a monochromatic
digital drawing interface, with the aim to identify different representational
approaches and determine whether timbral sound characteristics can be
communicated reliably through visual sketches. Results imply that the
development of a synthesiser exploiting sound-shape associations is feasible,
but a larger and more focused dataset is needed in followup studies.
