timidity: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/timidity - from package: timidity

You may install the required package with command apt-get install {package}

Error in other languages:
timidity: bevel nie gevind nie
timidity: comandă negăsită
timidity: comando não encontrado
timidity: commande introuvable
timidity: command not found
timidity: käsku ei ole
timidity: không tìm thấy lệnh
timidity: komanda nerasta
timidity: Kommando nicht gefunden.
timidity: kommandot finns inte
timidity: komut yok
timidity: nie znaleziono polecenia
timidity: níor aimsíodh an t-ordú
timidity: no se encontró la orden
timidity: no s'ha trobat l'ordre
timidity: opdracht niet gevonden
timidity: parancs nem található
timidity: perintah tidak ditemukan
timidity: príkaz nenájdený
timidity: příkaz nenalezen
timidity: команда не найдена
timidity: командата не е открита
timidity: 命令找不到
timidity: コマンドが見つかりません