A polythematic imitative fantasia of considerable length, 159 compases. It is marked D = dificil. It comprises four sections and is notable for it beautiful Beautiful dissonances and suspensions. Its structural scheme is as follows:
I) 1-46. An unusually broad beginning. Theme 1 is exceptionally long
II) 46-81. Fairly free with much crotchet motion in ascending direction, including motivic themes 2 + 3
III) 81-124. Voice pairs of 4a + 4b >> 4 as suelto theme
IV) 124-159. Free beginning >> theme 5 (borrowed from Narváez?) Almost identical treatment of same theme of Na 13 iv; dense sequential imitation again in crotchet motion + free K from 147.

The work has form similar to some of those by Daza: I—II | III—IV with 4 sections of almost the same length.

This fantasia is very difficult to play. The themes of sections I and IV are similar.
Jacobs gives E tuning with final cadence on A & signature of one flat. It therefore appears to be transposed mode 4 although mode with a final cadence on the dominant seems more likely from cadences and the range of the Superius.
n.b. some of the extravagant suspensions in cadential passages.