Non-native tones are considered challenging for adult second language speakers to perceive and produce. The current study examined the effect of a laboratory-based intensive training in improving American English speakers’ tone production. Participants’ task was to repeat Mandarin words after the model. There were two conditions in the experiment: in one condition, participants did not get any external feedback; whereas in the other condition, participants received detailed visual feedback, which was the pitch contour of their tone production alongside the native version. Eight participants completed training with no feedback and another eight participants were trained with visual feedback. Results revealed that participants in both groups did not improve their tone production after training, and participants trained with visual feedback did not show more improvement than those trained with no feedback. Given the lack of improvement in participants’ tone production after training, methodological and theoretical limitations with respect to the use of a repetition-based training paradigm are discussed.