Thomas Whythorne, Duos, or songs for two voices. Of the which, some be playne and easie to be sung or played on musicall instruments, and be made for yong beginners of both those sorts. And the rest of these duos be made and set foorth for those that be more perfect in singing or playing as aforesaid, all the which be divided into three parts (Thomas Este, London 1590).
52 didactic duos grouped in three parts. The title page gives detailed information about the different didactic purposes of the three groups:
The first [part], which doth begin at the first song, are made for a man and a childe to sing, or otherwise for voices or instruments of musicke, that be of the like compasse or distance in sound.
That is, 12 English sacred bicinia that set the Psalm 119, «Blessed are those that are undefiled»;
The second [part], which doth begin at the XXIII song, are made for two children to sing. Also they be aptly made for voices or musicall instruments, that be of the like compasse or distance in sound.
That is, 25 textless duos (Nos. 13-37);
And the third part which doth begin at the XXXVIII song (being all canons of two parts in one), be of divers compasses or distances, and therefore are to be used with voices or instruments of musicke accordingly.
That is, 15 textless canons (Nos. 38-52).
In his foreword to the reader, Whythorne claims that this is the first collection of didactic duos ever published in England. The mottos used as rubrics of the textless duos and the canons make us think that the composer knew Gramatio Metallo's duo collection.