Oxygen saturation levels in preterm infants that are too high or too low can lead to serious injury and infant death. Recent clinical guidelines recommend neonatal oxygen saturation levels (SpO2) should remain between 90% and 95% to avoid serious outcomes. Unfortunately, while current pulse oximeter sonification can effectively provide information regarding SpO2 levels that are increasing or decreasing, it does not support the detection of specific SpO2 target range deviations. The purpose of the present study was to test whether a novel auditory display that adds ‘tremolo’ to the current pulse oximeter tone whenever oxygen saturation levels are outside the target range, would improve the detection of out-ofrange SpO2 levels. The experiment examined whether participants could identify SpO2 range and the moment of transition into and out of the SpO2 target zone with 15 percentage points greater accuracy when they used either a novel Tremolo sonification or a Beacon sonification, compared with a standard LogLinear pulse oximeter sonification,. Participants using the Tremolo or Beacon sonification identified oxygen saturation range and transitions into and out of target zone more accurately than participants using the LogLinear sonification, exceeding the 15-percentage point criterion. There was no evidence that participants identified direction of change in oxygen saturation any differently with the Tremolo or Beacon sonification than with the LogLinear sonification. Further research in clinical settings is required to confirm these findings; however, the results suggest that a Tremolo pulse oximeter sonification has the potential to improve oxygen saturation level targeting in preterm neonates.