There is a great controversy among scholars on the use of musical instruments. Most scholars judged it to be impermissible, citing a Prophetic hadith that prohibits it, while some others permitted it. To be in the safe side, use non-string and non-wind instruments, such as drums, tambourine, and other percussion instruments.
Once, I met the chanter Sami Yusuf in Canada, where he made several performances. I cannot disapprove of his use of music in chants. Unless there are evident considerations that entail prohibition, no decisive judgment should be given on such controversial issues as the use of music. So, I do not blame Yusuf or others who use music in chants; however, this by no means implies my approval.