The development of the ability to sing or play in tune is one of the most critical tasks in music training. In music education, melodic patterns are usually learned by imitative processes (modelling). Once modelled, pitch sounds are then associ-ated to a representation according to a syllabic system such as the Guidonian system - or an arbitrary single syllable - or western graphic notation system symbols. From a didactic standpoint, few advances have been made in this area besides the use of audio-supported guides and existing software, which use a microphone to analyse the input and estimate the pitch or fundamental frequency of the given tone. However, these programmes lack the necessary analytical algo-rithm to provide the student with precise feedback on their execution; and also they do not provide adequate noise-robust solutions to minimize the student assessment error rate. The ongoing research discussed in this article focuses on Cantus, a new software solution expressly designed as an assessment and diagnosis tool for online training and assessment of vocal musical intonation at the initial stages of music education. Cantus software embodies the latest research on real-time analy-sis of audio stream, which permits the teacher to customize music training by means of recording patterns and embedding them into the programme. The study presented in this article includes the design, implementation and assessment of Cantus by music teachers. The pilot study for the software assessment includes a sample of 21 music teachers working at thirteen music schools in Valencia, Spain. These teachers worked with the software at their own pace for a week in order to evaluate it. Subsequently, a two-part questionnaire was filled in with (1) ques-tions related to demographics, professional experience and the use of ITC; and (2) questions related to the software's technical and didactic aspects. The question-naire also included three open questions related to Cantus, namely advantages, issues and suggestions. The results show an excellent reception by teachers, who consider this software as a highly adequate music training tool at the initial stages of music education.